@article {1809601,
	title = {Predicting overstriding with wearable IMUs during treadmill and overground running},
	journal = {Nature Scientific Reports},
	volume = {14},
	number = {6347},
	year = {2024},
	abstract = {Running injuries are prevalent, but their exact mechanisms remain unknown largely due to limited real-world biomechanical analysis. Reducing overstriding, the horizontal distance that the foot lands ahead of the body, may be relevant to reducing injury risk. Here, we leverage the geometric relationship between overstriding and lower extremity sagittal segment angles to demonstrate that wearable inertial measurement units (IMUs) can predict overstriding during treadmill and overground running in the laboratory. Ten recreational runners matched their strides to a metronome to systematically vary overstriding during constant-speed treadmill running and showed similar overstriding variation during comfortable-speed overground running. Linear mixed models were used to analyze repeated measures of overstriding and sagittal segment angles measured with motion capture and IMUs. Sagittal segment angles measured with IMUs explained 95\% and 98\% of the variance in overstriding during treadmill and overground running, respectively. We also found that sagittal segment angles measured with IMUs correlated with peak braking force and explained 88\% and 80\% of the variance during treadmill and overground running, respectively. This study highlights the potential for IMUs to provide insights into landing and loading patterns over time in real-world running environments, and motivates future research on feedback to modify form and prevent injury.},
	url = {https://www.nature.com/articles/s41598-024-56888-4},
	author = {Baker, Lauren M. and Ali Yawar and Lieberman, Daniel E. and Walsh, Conor J.}
}
@article {1803561,
	title = {Lightweight active back exosuit reduces muscular effort during an hour-long order picking task},
	journal = {Nature Communications Engineering},
	volume = {3},
	number = {35},
	year = {2024},
	abstract = {Occupational back exoskeletons and exosuits aim to reduce low back injuries in the workplace. For these technologies to be adopted, it is important that they provide biomechanical benefits to the wearer and do not disrupt job performance. To address this challenge, here we developed a lightweight, soft, active back exosuit that can autonomously control virtual impedance to apply differing assistance during lowering and lifting. In usability tests, participants rated the exosuit as easy to learn and use and reported feeling confident while wearing it. In an experiment involving an hour-long order picking task we demonstrated that the exosuit reduced peak and median muscle activations in the back by 18\% and 20\%, respectively. Despite the complexity of the movements required, such as walking, bending, and navigating around obstacles while lifting boxes from under a rack, our controller demonstrated impressive robustness with only 14 mistriggers out of 9600 lifts (0.1\%). The results of this research suggest that active exosuit technology has the potential to be a highly usable solution to aid warehouse workers in real-world settings.},
	url = {https://www.nature.com/articles/s44172-024-00180-w$\#$citeas},
	author = {Jinwon Chung and D. Adam Quirk and Megan Applegate and Michael Rouleau and Nathalie Degenhardt and Ignacio Galiana and Diane Dalton and Louis N. Awad and Walsh, Conor J.}
}
@article {1803256,
	title = {The effect of a soft active back support exosuit on trunk motion and thoracolumbar spine loading during squat and stoop lifts},
	journal = {Ergonomics},
	year = {2024},
	abstract = {Back support exosuits aim to reduce tissue demands and thereby risk of injury and pain. However, biomechanical analyses of soft active exosuit designs have been limited. The objective of this study was to evaluate the effect of a soft active back support exosuit on trunk motion and thoracolumbar spine loading in participants performing stoop and squat lifts of 6 and 10 kg crates, using participant-specific musculoskeletal models. The exosuit did not change overall trunk motion but affected lumbo-pelvic motion slightly, and reduced peak compressive and shear vertebral loads at some levels, although shear increased slightly at others. This study indicates that soft active exosuits have limited kinematic effects during lifting, and can reduce spinal loading depending on the vertebral level. These results support the hypothesis that a soft exosuit can assist without limiting trunk movement or negatively impacting skeletal loading and have implications for future design and ergonomic intervention efforts.},
	url = {https://www.tandfonline.com/doi/full/10.1080/00140139.2024.2320355},
	author = {Jacob J. Banks and David A. Quirk and Jinwon Chung and Jason M. Cherin and Walsh, Conor J. and Dennis E. Anderson}
}
@article {1796801,
	title = {A Portable, Neurostimulation-Integrated, Force Measurement Platform for the Clinical Assessment of Plantarflexor Central Drive},
	journal = {Bioengineering},
	volume = {11},
	number = {2},
	year = {2024},
	abstract = {Plantarflexor central drive is a promising biomarker of neuromotor impairment; however, routine clinical assessment is hindered by the unavailability of force measurement systems with integrated neurostimulation capabilities. In this study, we evaluate the accuracy of a portable, neurostimulation-integrated, plantarflexor force measurement system we developed to facilitate the assessment of plantarflexor neuromotor function in clinical settings. Two experiments were conducted with the Central Drive System (CEDRS). To evaluate accuracy, experiment $\#$1 included 16 neurotypical adults and used intra-class correlation (ICC2,1) to test agreement of plantarflexor strength capacity measured with CEDRS versus a stationary dynamometer. To evaluate validity, experiment $\#$2 added 26 individuals with post-stroke hemiparesis and used one-way ANOVAs to test for between-limb differences in CEDRS{\textquoteright} measurements of plantarflexor neuromotor function, comparing neurotypical, non-paretic, and paretic limb measurements. The association between paretic plantarflexor neuromotor function and walking function outcomes derived from the six-minute walk test (6MWT) were also evaluated. CEDRS{\textquoteright} measurements of plantarflexor neuromotor function showed high agreement with measurements made by the stationary dynamometer (ICC = 0.83,\&nbsp;p\&nbsp;\&lt; 0.001). CEDRS{\textquoteright} measurements also showed the expected between-limb differences (p{\textquoteright}s \&lt; 0.001) in maximum voluntary strength (Neurotypical: 76.21 {\textpm} 13.84 ft-lbs., Non-paretic: 56.93 {\textpm} 17.75 ft-lbs., and Paretic: 31.51 {\textpm} 14.08 ft-lbs.), strength capacity (Neurotypical: 76.47 {\textpm} 13.59 ft-lbs., Non-paretic: 64.08 {\textpm} 14.50 ft-lbs., and Paretic: 44.55 {\textpm} 14.23 ft-lbs.), and central drive (Neurotypical: 88.73 {\textpm} 1.71\%, Non-paretic: 73.66\% {\textpm} 17.74\%, and Paretic: 52.04\% {\textpm} 20.22\%). CEDRS-measured plantarflexor central drive was moderately correlated with 6MWT total distance (r = 0.69,\&nbsp;p\&nbsp;\&lt; 0.001) and distance-induced changes in speed (r = 0.61,\&nbsp;p\&nbsp;= 0.002). CEDRS is a clinician-operated, portable, neurostimulation-integrated force measurement platform that produces accurate measurements of plantarflexor neuromotor function that are associated with post-stroke walking ability.},
	url = {https://www.mdpi.com/2306-5354/11/2/137},
	author = {Collimore, Ashley N. and Alvarez, Jonathan T. and David A. Sherman and Lucas F. Gerez and Noah Barrow and Dabin K. Choe and Stuart Binder-Macleod and Walsh, Conor J. and Louis N. Awad}
}
@article {1796281,
	title = {Educational Soft Underwater Robot with an Electromagnetic Actuation},
	journal = {Soft Robotics},
	year = {2024},
	abstract = {As demonstrated by the Soft Robotics Toolkit Platform, compliant robotics pose an exciting educational opportunity. Underwater robotics using soft undulating fins is an expansive research topic with applications such as exploration of underwater life or replicating 3d swarm behavior. To make this research area accessible for education we developed Educational Soft Underwater Robot with Electromagnetic Actuation (ESURMA), a humanoid soft underwater robot. We achieved advances in simplicity, modularity, and performance by implementing electromagnetic actuation into the caudal fin. An electromagnet, including electronics, is placed in a waterproof housing, and permanent magnets are embedded in a soft silicone cast tail. The force from their magnetic interaction results in a bending movement of the tail. The magnetic actuation is simple to implement and requires no mechanical connection between the actuated component and the electrically controlled coil. This enables robust waterproofing and makes the device fully modular. Thanks to the direct and immediate transmission of force, experimental flapping frequencies of 14 Hz were achieved, an order of magnitude higher compared to pneumatically actuated tails. The completely silent actuation of the caudal fin enables a maximum swimming speed of 14.3 cm/s. With its humanoid shape, modular composition, and cost efficiency ESURMA represents an attractive platform for education and demonstrates an alternative method of actuating soft structures.},
	url = {https://www.liebertpub.com/doi/full/10.1089/soro.2021.0181},
	author = {Robert Hennig and Alex Beaudette and Holly M. Golecki and Walsh, Conor J.}
}
@article {1796071,
	title = {Combining soft robotics and telerehabilitation for improving motor function after stroke},
	journal = {Wearable Technologies},
	volume = {5},
	year = {2024},
	abstract = {Telerehabilitation and robotics, either traditional rigid or soft, have been extensively studied and used to improve hand functionality after a stroke. However, a limited number of devices combined these two technologies to such a level of maturity that was possible to use them at the patients{\textquoteright} home, unsupervised. Here we present a novel investigation that demonstrates the feasibility of a system that integrates a soft inflatable robotic glove, a cloud-connected software interface, and a telerehabilitation therapy. Ten chronic moderate-to-severe stroke survivors independently used the system at their home for 4\&nbsp;weeks, following a software-led therapy and being in touch with occupational therapists. Data from the therapy, including automatic assessments by the robot, were available to the occupational therapists in real-time, thanks to the cloud-connected capability of the system. The participants used the system intensively (about five times more movements per session than the standard care) for a total of more than 8\&nbsp;hr of therapy on average. We were able to observe improvements in standard clinical metrics (FMA +3.9\&nbsp;{\textpm}\&nbsp;4.0,\&nbsp;p\&nbsp;\&lt;\&nbsp;.05, COPM-P\&nbsp;+\&nbsp;2.5\&nbsp;{\textpm}\&nbsp;1.3,\&nbsp;p\&nbsp;\&lt;\&nbsp;.05, COPM-S\&nbsp;+\&nbsp;2.6\&nbsp;{\textpm}\&nbsp;1.9,\&nbsp;p\&nbsp;\&lt;\&nbsp;.05, MAL-AOU +6.6\&nbsp;{\textpm}\&nbsp;6.5,\&nbsp;p\&nbsp;\&lt;\&nbsp;.05) and range of motion (+88\%) at the end of the intervention. Despite being small, these improvements sustained at follow-up, 2\&nbsp;weeks after the end of the therapy. These promising results pave the way toward further investigation for the deployment of combined soft robotic/telerehabilitive systems at-home for autonomous usage for stroke rehabilitation.},
	url = {https://www.cambridge.org/core/journals/wearable-technologies/article/combining-soft-robotics-and-telerehabilitation-for-improving-motor-function-after-stroke/60A43ECC3F957B2C89A4CB6100E16D88},
	author = {Tommaso Proietti and Kristin Nuckols and Jesse Grupper and Diogo Schwerz de Lucena and Bianca Inirio and Kelley Porazinski and Diana Wagner and Tazzy Cole and Christina Glover and Sarah Mendelowitz and Maxwell Herman and Joan Breen and David Lin and Conor Walsh}
}
@article {1792636,
	title = {Soft robotic apparel to avert freezing of gait in Parkinson{\textquoteright}s disease.},
	journal = {Nature Medicine},
	year = {2024},
	abstract = {Freezing of gait (FoG) is a profoundly disruptive gait disturbance in Parkinson{\textquoteright}s disease, causing unintended stops while walking. Therapies for FoG reveal modest and transient effects, resulting in a lack of effective treatments. Here we show proof of concept that FoG can be averted using soft robotic apparel that augments hip flexion. The wearable garment uses cable-driven actuators and sensors, generating assistive moments in concert with biological muscles. In this\&nbsp;n-of-1 trial with five repeated measurements spanning 6 months, a 73-year-old male with Parkinson{\textquoteright}s disease and substantial FoG demonstrated a robust response to robotic apparel. With assistance, FoG was instantaneously eliminated during indoor walking (0\% versus 39 {\textpm} 16\% time spent freezing when unassisted), accompanied by 49 {\textpm} 11 m (+55\%) farther walking compared to unassisted walking, faster speeds (+0.18 m s-1) and improved gait quality (-25\% in gait variability). FoG-targeting effects were repeatable across multiple days, provoking conditions and environment contexts, demonstrating potential for community use. This study demonstrated that FoG was averted using soft robotic apparel in an individual with Parkinson{\textquoteright}s disease, serving as an impetus for technological advancements in response to this serious yet unmet need.},
	url = {https://doi.org/10.1038/s41591-023-02731-8},
	author = {Jinsoo Kim and Franchino Porciuncula and Hee Doo Yang and Nicholas Wendel and Teresa Baker and Andrew Chin and Terry D. Ellis and Walsh, Conor J.}
}
@article {1792631,
	title = {Wearable robot helps man with Parkinson{\textquoteright}s disease to walk.},
	journal = {Nature Medicine},
	year = {2024},
	abstract = {In one person with Parkinson{\textquoteright}s disease, freezing of gait was averted through the use of a soft robotic apparel that provided a moderate level of hip-flexion assistance during the swing phase of walking. This approach delivered instantaneous effects and consistently improved walking quality and function across a range of conditions.},
	url = {https://doi.org/10.1038/s41591-023-02756-z},
	author = {Conor Walsh and Terry Ellis}
}
@article {1809606,
	title = {Effects of high-intensity gait training with and without soft robotic exosuits in people post-stroke: a development-of-concept pilot crossover trial},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {20},
	number = {148},
	year = {2023},
	abstract = {
	Introduction



	High-intensity gait training is widely recognized as an effective rehabilitation approach after stroke. Soft robotic exosuits that enhance post-stroke gait mechanics have the potential to improve the rehabilitative outcomes achieved by high-intensity gait training. The objective of this\&nbsp;development-of-concept\&nbsp;pilot crossover study was to evaluate the outcomes achieved by high-intensity gait training with versus without soft robotic exosuits.



	Methods



	In this 2-arm pilot crossover study, four individuals post-stroke completed twelve visits of speed-based, high-intensity gait training: six consecutive visits of Robotic Exosuit Augmented Locomotion (REAL) gait training and six consecutive visits without the exosuit (CONTROL). The intervention arms were counterbalanced across study participants and separated by 6 + weeks of washout. Walking function was evaluated before and after each intervention using 6-minute walk test (6MWT) distance and 10-m walk test (10mWT) speed. Moreover, 10mWT speeds were evaluated before each training visit, with the time-course of change in walking speed computed for each intervention arm. For each participant, changes in each outcome were compared to minimal clinically-important difference (MCID) thresholds. Secondary analyses focused on changes in propulsion mechanics and associated biomechanical metrics.



	Results



	Large between-group effects were observed for 6MWT distance (d = 1.41) and 10mWT speed (d = 1.14). REAL gait training resulted in an average pre-post change of 68 {\textpm} 27\&nbsp;m (p = 0.015) in 6MWT distance, compared to a pre-post change of 30 {\textpm} 16\&nbsp;m (p = 0.035) after CONTROL gait training. Similarly, REAL training resulted in a pre-post change of 0.08 {\textpm} 0.03\&nbsp;m/s (p = 0.012) in 10mWT speed, compared to a pre-post change of 0.01 {\textpm} 06\&nbsp;m/s (p = 0.76) after CONTROL. For both outcomes, 3 of 4 (75\%) study participants surpassed MCIDs after REAL training, whereas 1 of 4 (25\%) surpassed MCIDs after CONTROL training. Across the training visits, REAL training resulted in a 1.67 faster rate of improvement in walking speed. Similar patterns of improvement were observed for the secondary gait biomechanical outcomes, with REAL training resulting in significantly improved paretic propulsion for 3 of 4 study participants (p \&lt; 0.05) compared to 1 of 4 after CONTROL.



	Conclusion



	Soft robotic exosuits have the potential to enhance the rehabilitative outcomes produced by high-intensity gait training after stroke. Findings of this\&nbsp;development-of-concept\&nbsp;pilot crossover trial motivate continued development and study of the REAL gait training program.

},
	url = {https://link.springer.com/article/10.1186/s12984-023-01267-9},
	author = {Franchino Porciuncula and Dheepak Arumukhom Revi and Teresa C. Baker and Sloutsky, Regina and Walsh, Conor J. and Terry D. Ellis and Louis N. Awad}
}
@article {1796276,
	title = {Artificial intelligence meets medical robotics},
	journal = {Science},
	volume = {381},
	number = {6654},
	year = {2023},
	abstract = {Artificial intelligence (AI) applications in medical robots are bringing a new era to medicine. Advanced medical robots can perform diagnostic and surgical procedures, aid rehabilitation, and provide symbiotic prosthetics to replace limbs. The technology used in these devices, including computer vision, medical image analysis, haptics, navigation, precise manipulation, and machine learning (ML), could allow autonomous robots to carry out diagnostic imaging, remote surgery, surgical subtasks, or even entire surgical procedures. Moreover, AI in rehabilitation devices and advanced prosthetics can provide individualized support, as well as improved functionality and mobility (see the figure). The combination of extraordinary advances in robotics, medicine, materials science, and computing could bring safer, more efficient, and more widely available patient care in the future.\&nbsp;{\textendash}Gemma K. Alderton},
	url = {https://www.science.org/doi/full/10.1126/science.adj3312},
	author = {Michael Yip and Septimiu Salcudean and Ken Goldberg and Kaspar Althoefer and Arianna Menciassi and Justin D. Opfermann and Krieger, Axel and Krithika Swaminathan and Walsh, Conor J. and He (Helen) Huang and I-Chieh Lee}
}
@article {1747441,
	title = {Effects of a soft robotic exosuit on the quality and speed of overground walking depends on walking ability after stroke},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {20},
	number = {113},
	year = {2023},
	abstract = {
	Background Soft robotic exosuits can provide partial dorsiflexor and plantarflexor support in parallel with paretic muscles to improve poststroke walking capacity. Previous results indicate that baseline walking ability may impact a user{\textquoteright}s ability to leverage the exosuit assistance, while the effects on continuous walking, walking stability, and muscle slacking have not been evaluated. Here we evaluated the effects of a portable ankle exosuit during continuous comfortable overground walking in 19 individuals with chronic hemiparesis. We also compared two speed-based subgroups (threshold: 0.93 m/s) to address poststroke heterogeneity.



	Methods\&nbsp;We refined a previously developed portable lightweight soft exosuit to support continuous overground walking. We compared five minutes of continuous walking in a laboratory with the exosuit to walking without the exosuit in terms of ground clearance, foot landing and propulsion, as well as the energy cost of transport, walking stability and plantarflexor muscle slacking.



	Results\&nbsp;Exosuit assistance was associated with improvements in the targeted gait impairments: 22\% increase in ground clearance during swing, 5{\textdegree} increase in foot-to-floor angle at initial contact, and 22\% increase in the center-of- mass propulsion during push-off. The improvements in propulsion and foot landing contributed to a 6.7\% (0.04 m/s) increase in walking speed (R2\&nbsp;= 0.82). This enhancement in gait function was achieved without deterioration in muscle effort, stability or cost of transport. Subgroup analyses revealed that all individuals profited from ground clearance support, but slower individuals leveraged plantarflexor assistance to improve propulsion by 35\% to walk 13\% faster, while faster individuals did not change either.



	Conclusions\&nbsp;The immediate restorative benefits of the exosuit presented here underline its promise for rehabilitative gait training in poststroke individuals.

},
	url = {https://doi.org/10.1186/s12984-023-01231-7},
	author = {Sloot, Lizeth H. and Lauren M. Baker  Richard W. Nucko and Jaehyun Bae and Franchino Porciuncula and Blandine F. Cl{\'e}ment and Christopher Siviy and Richard W. Nuckols and Teresa Baker and Sloutsky, Regina and Dabin K. Choe and O{\textquoteright}Donnell, Kathleen and Terry D. Ellis and Louis N. Awad and Walsh, Conor J.}
}
@article {1738131,
	title = {Tunable, Textile-Based Joint Impedance Module for Soft Robotic Applications},
	journal = {Soft Robotics},
	volume = {10},
	number = {4},
	year = {2023},
	abstract = {The design of soft actuators is often focused on achieving target trajectories or delivering specific forces and torques, rather than controlling the impedance of the actuator. This article outlines a new soft, tunable pneumatic impedance module based on an antagonistic actuator setup of textile-based pneumatic actuators intended to deliver bidirectional torques about a joint. Through mechanical programming of the actuators (select tuning of geometric parameters), the baseline torque to angle relationship of the module can be tuned. A high bandwidth fluidic controller that can rapidly modulate the pressure at up to 8 Hz in each antagonistic actuator was also developed to enable tunable impedance modulation. This high bandwidth was achieved through the characterization and modeling of the proportional valves used, derivation of a fluidic model, and derivation of control equations. The resulting impedance module was capable of modulating its stiffness from 0 to 100 Nm/rad, at velocities up to 120{\textdegree}/s and emulating asymmetric and nonlinear stiffness profiles, typical in wearable robotic applications.},
	url = {https://doi.org/10.1089/soro.2021.0173},
	author = {Ciar{\'a}n T. O{\textquoteright}Neill and Harrison T. Young and Cameron J. Hohimer and Tommaso Proietti and Mo Rastgaar and Panagiotis Artemiadis and Walsh, Conor J.}
}
@article {1738126,
	title = {Evaluating adaptiveness of an active back exosuit for dynamic lifting and maximum range of motion},
	journal = {Ergonomics},
	year = {2023},
	abstract = {
	Back exosuits deliver mechanical assistance to reduce the risk of back injury, however, minimising restriction is critical for adoption. We developed the adaptive impedance controller to minimise restriction while maintaining assistance by modulating impedance based on the user{\textquoteright}s movement direction and nonlinear sine curves. The objective of this study was to compare active assistance, delivered by a back exosuit via our adaptive impedance controller, to three levels of assistance from passive elastics. Fifteen participants completed five experimental blocks (4 exosuits and 1 no-suit) consisting of a maximum flexion and a constrained lifting task. While a higher stiffness elastic reduced back extensor muscle activity by 13\%, it restricted maximum range of motion (RoM) by 13{\textdegree}. The adaptive impedance approach did not restrict RoM while reducing back extensor muscle activity by 15\%, when lifting. This study highlights an adaptive impedance approach might improve usability by circumventing the assistance-restriction tradeoff inherent to passive approaches.



	Practitioner summary: This study demonstrates a soft active exosuit that delivers assistance with an adaptive impedance approach can provide reductions in overall back muscle activity without the impacts of restricted range of motion or perception of restriction and discomfort.

},
	url = {https://doi.org/10.1080/00140139.2023.2240044},
	author = {D. Adam Quirk and Jinwon Chung and Megan Applegate and Jason M. Cherin and Diane M. Dalton and Lou N. Awad and Walsh, Conor J.}
}
@article {1709561,
	title = {Ankle-targeted exosuit resistance increases paretic propulsion in people post-stroke},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {20},
	number = {85},
	year = {2023},
	abstract = {
	Background



	Individualized, targeted, and intense training is the hallmark of successful gait rehabilitation in people post-stroke. Specifically, increasing use of the impaired ankle to increase propulsion during the stance phase of gait has been linked to higher walking speeds and symmetry. Conventional progressive resistance training is one method used for individualized and intense rehabilitation, but often fails to target paretic ankle plantarflexion during walking. Wearable assistive robots have successfully\&nbsp;assisted\&nbsp;ankle-specific mechanisms to increase paretic propulsion in people post-stroke, suggesting their potential to provide targeted\&nbsp;resistance\&nbsp;to increase propulsion, but this application remains underexamined in this population. This work investigates the effects of targeted stance-phase plantarflexion resistance training with a soft ankle exosuit on propulsion mechanics in people post-stroke.



	Methods



	We conducted this study in nine individuals with chronic stroke and tested the effects of three resistive force magnitudes on peak paretic propulsion, ankle torque, and ankle power while participants walked on a treadmill at their comfortable walking speeds. For each force magnitude, participants walked for 1\&nbsp;min while the exosuit was inactive, 2\&nbsp;min with active resistance, and 1\&nbsp;min with the exosuit inactive, in sequence. We evaluated changes in gait biomechanics during the active resistance and post-resistance sections relative to the initial inactive section.



	Results



	Walking with active resistance increased paretic propulsion by more than the minimal detectable change of 0.8\&nbsp;\%body weight at all tested force magnitudes, with an average increase of 1.29 {\textpm} 0.37\&nbsp;\%body weight at the highest force magnitude. This improvement corresponded to changes of 0.13 {\textpm} 0.03\&nbsp;N m kg- 1\&nbsp;in peak biological ankle torque and 0.26 {\textpm} 0.04\&nbsp;W kg- 1\&nbsp;in peak biological ankle power. Upon removal of resistance, propulsion changes persisted for 30\&nbsp;seconds with an improvement of 1.49 {\textpm} 0.58\&nbsp;\%body weight after the highest resistance level and without compensatory involvement of the unresisted joints or limb.



	Conclusions



	Targeted exosuit-applied functional resistance of paretic ankle plantarflexors can elicit the latent propulsion reserve in people post-stroke. After-effects observed in propulsion highlight the potential for learning and restoration of propulsion mechanics. Thus, this exosuit-based resistive approach may offer new opportunities for individualized and progressive gait rehabilitation.

},
	url = {https://link.springer.com/article/10.1186/s12984-023-01204-w$\#$citeas},
	author = {Krithika Swaminathan and Franchino Porciuncula and Sungwoo Park and Harini Kannan and Julien Erard and Nicholas Wendel and Teresa Baker and Terry D. Ellis and Louis N. Awad and Walsh, Conor J.}
}
@article {1698701,
	title = {Anti-inflammatory therapy enables robot-actuated regeneration of aged muscle },
	journal = {Science Robotics},
	volume = {8},
	number = {76},
	year = {2023},
	abstract = {Robot-actuated mechanical loading (ML){\textendash}based therapies ({\textquotedblleft}mechanotherapies{\textquotedblright}) can promote regeneration after severe skeletal muscle injury, but the effectiveness of such approaches during aging is unknown and may be influenced by age-associated decline in the healing capacity of skeletal muscle. To address this knowledge gap, this work used a noninvasive, load-controlled robotic device to impose highly defined tissue stresses to evaluate the age dependence of ML on muscle repair after injury. The response of injured muscle to robot-actuated cyclic compressive loading was found to be age sensitive, revealing not only a lack of reparative benefit of ML on injured aged muscles but also exacerbation of tissue inflammation. ML alone also disrupted the normal regenerative processes of aged muscle stem cells. However, these negative effects could be reversed by introducing anti-inflammatory therapy alongside ML application, leading to enhanced skeletal muscle regeneration even in aged mice.},
	url = {https://www.science.org/doi/10.1126/scirobotics.add9369?url_ver=Z39.88-2003\&rfr_id=ori:rid:crossref.org\&rfr_dat=cr_pub\%20\%200pubmed},
	author = {S. L. MCNAMARA and B. R. Seo and B. R. Freedman and E. B. Roloson and Alvarez, J.T. and C. T. O{\textquoteright}Neill and H. H. Vandenburgh and C. J. Walsh and D. J. Mooney}
}
@article {1698581,
	title = {Design and evaluation of an independent 4-week, exosuit-assisted, post-stroke community walking program},
	journal = {Annals of the New York Academy of Sciences},
	year = {2023},
	abstract = {Chronic impairment in the paretic ankle following stroke often requires that individuals use compensatory patterns such as asymmetric propulsion to achieve effective walking speeds needed for community engagement. Ankle exosuit assistance can provide ankle biomechanical benefit in the lab, but such environments inherently limit the amount of practice available. Community walking studies without exosuits can provide massed practice and benefit walking speed but are limited in their ability to assist proper mechanics. In this study, we combined the positive aspects of community training with those of exosuit assistance. We developed and evaluated a community Robotic Exosuit Augmented Locomotion (cREAL) program. Four participants in the chronic stage of stroke independently used our community ankle exosuit for walking in the community 3{\textendash}5 days/week for 4 weeks. We performed lab evaluations before and after the 4-week program. Two participants significantly improved their unassisted paretic propulsion by an average of 27\% after the program and walked on average 4001 steps/day more in the week following the program. Despite the small number of participants, this study provides preliminary evidence for the potential of exosuits to augment gait training and rehabilitation in the community.},
	url = {https://nyaspubs.onlinelibrary.wiley.com/doi/10.1111/nyas.14998},
	author = {Richard W. Nuckols and Chih-Kang Chang and Daekyum Kim and Eckert-Erdheim, Asa and Dorothy Orzel and Lauren Baker and Teresa Baker and Nicholas C. Wendel and Brendan Quinlivan and Patrick Murphy and Jesse Grupper and Jacqueline Villalobos and Louis N. Awad and Terry D. Ellis and Walsh, Conor J.}
}
@article {1696651,
	title = {In-Situ Measurement of Multi-Axis Torques Applied by Wearable Soft Robots for Shoulder Assistance},
	journal = {IEEE Transactions on Medical Robotics and Bionics},
	volume = {5},
	number = {2},
	year = {2023},
	pages = {363-374},
	abstract = {While a number of wearable soft robotic devices have been proposed to assist the shoulder, limited efforts have been made to quantify the amount of torque they apply to the body. Most work to-date has assessed soft actuator performance with simple benchtop experiments that may not be representative of the boundary conditions on the human body. We propose a new methodology to measure torques directly in-situ on the body and then use this technique to make a detailed comparison of two versions of a soft wearable shoulder assistance robot. The impact of a number of factors are considered, such as actuator design, garment anchoring, material hysteresis, arm pose, and inflation pressure. Many of these factors are not present on the benchtop and are found to significantly affect torque production. We compare results obtained on a simple benchtop test fixture with two on-body settings: an idealized mannequin and actual human subjects. The mannequin and human results were similar, but differed significantly from the benchtop, further motivating the need for on-body testing. Moving forward, we believe that the ability to directly quantify device performance in-situ will be critical to develop new design, modeling, and control strategies for wearable robots.},
	url = {https://ieeexplore.ieee.org/document/10075492?source=authoralert},
	author = {C. M. McCann and Hohimer, C. J. and C. T. O{\textquoteright}Neill and H. T. Young and K. Bertoldi and C. J. Walsh}
}
@article {1666864,
	title = {Reducing back exertion and improving confidence of individuals with low back pain with a back exosuit: A feasibility study for use in BACPAC},
	journal = {Pain Medicine},
	year = {2023},
	abstract = {
	Objective



	Low back pain (LBP) is hallmarked by activity limitations, especially for tasks involving bending. Back exosuit technology reduces low back discomfort and improves self-efficacy of individuals with LBP during bending and lifting tasks. However, the biomechanical efficacy of these devices in individuals with LBP is unknown. This study sought to determine biomechanical and perceptual effects of a soft active back exosuit designed to assist individuals with LBP sagittal plane bending. To understand patient-reported usability and use cases for this device.



	Methods



	Fifteen individuals with LBP performed two experimental lifting blocks once with and without an exosuit. Trunk biomechanics were measured by muscle activation amplitudes, and whole-body kinematics and kinetics. To evaluate device perception, participants rated task effort, low back discomfort, and their level of concern completing daily activities.



	Results



	The back exosuit reduced peak back extensor: moments by 9\%, and muscle amplitudes by 16\% when lifting. There were no changes in abdominal co-activation and small reductions maximum trunk flexion compared to lifting without an exosuit. Participants reported lower task effort, back discomfort, and concern about bending and lifting with an exosuit compared to without.



	Conclusion



	This study demonstrates a back exosuit not only imparts perceptual benefits of reduced task effort, discomfort, and increased confidence in individuals with LBP but that it achieves these benefits through measurable biomechanical reductions in back extensor effort. The combined effect of these benefits implies back exosuits might be a potential therapeutic aid to augment physical therapy, exercises, or daily activities.

},
	url = {https://doi.org/10.1093/pm/pnad003},
	author = {D. A. Quirk and J. Chung and Schiller, G. and J. M. Cherin and P. Arens and D. Sherman and E. Zeligson and D. Dalton and L. N. Awad and C. J. Walsh}
}
@article {1665493,
	title = {Age-Related Reliability of B-Mode Analysis for Tailored Exosuit Assistance},
	journal = {Sensors},
	volume = {23},
	number = {3},
	year = {2023},
	abstract = {In the field of wearable robotics, assistance needs to be individualized for the user to maximize benefit. Information from muscle fascicles automatically recorded from brightness mode (B-mode) ultrasound has been used to design assistance profiles that are proportional to the estimated muscle force of young individuals. There is also a desire to develop similar strategies for older adults who may have age-altered physiology. This study introduces and validates a ResNet + 2x-LSTM model for extracting fascicle lengths in young and older adults. The labeling was generated in a semimanual manner for young (40,696 frames) and older adults (34,262 frames) depicting B-mode imaging of the medial gastrocnemius. First, the model was trained on young and tested on both young (R2 = 0.85, RMSE = 2.36 {\textpm} 1.51 mm, MAPE = 3.6\%, aaDF = 0.48 {\textpm} 1.1 mm) and older adults (R 2 = 0.53, RMSE = 4.7 {\textpm} 2.51 mm, MAPE = 5.19\%, aaDF = 1.9 {\textpm} 1.39 mm). Then, the performances were trained across all ages (R2 = 0.79, RMSE = 3.95 {\textpm} 2.51 mm, MAPE = 4.5\%, aaDF = 0.67 {\textpm} 1.8 mm). Although age-related muscle loss affects the error of the tracking methodology compared to the young population, the absolute percentage error for individual fascicles leads to a small variation of 3{\textendash}5\%, suggesting that the error may be acceptable in the generation of assistive force profiles.},
	url = {https://www.mdpi.com/1424-8220/23/3/1670},
	author = {Letizia Gionfrida and Richard W. Nuckols and Walsh, Conor J. and Robert D. Howe}
}
@article {1665181,
	title = {Restoring arm function with a soft robotic wearable for individuals with amyotrophic lateral sclerosis},
	journal = {Science Translational Medicine},
	volume = {15},
	number = {681},
	year = {2023},
	abstract = {Despite promising results in the rehabilitation field, it remains unclear whether upper limb robotic wearables, e.g., for people with physical impairments resulting from neurodegenerative disease, can be made portable and suitable for everyday use. We present a lightweight, fully portable, textile-based, soft inflatable wearable robot for shoulder elevation assistance that provides dynamic active support to the upper limbs. The technology is mechanically transparent when unpowered, can quantitatively assess free movement of the user, and adds only 150\&nbsp;grams of weight to each upper limb. In 10 individuals with amyotrophic lateral sclerosis (ALS) with different degrees of neuromuscular impairment, we demonstrated immediate improvement in the active range of motion and compensation for continuing physical deterioration in two individuals with ALS over 6 months. Along with improvements in movement, we show that this robotic wearable can improve functional activity without any training, restoring performance of basic activities of daily living. In addition, a reduction in shoulder muscle activity and perceived muscular exertion, coupled with increased endurance for holding objects, highlight the potential of this device to mitigate the impact of muscular fatigue for patients with ALS. These results represent a further step toward everyday use of assistive, soft, robotic wearables for the upper limbs.},
	url = {https://www.science.org/doi/10.1126/scitranslmed.add1504},
	author = {Tommaso Proietti and Ciaran O{\textquoteright}Neill and Lucas Gerez and Tazzy Cole and Sarah Mendelowitz and Kristin Nuckols and Cameron Hohimer and David Lin and Paganoni, Sabrina and Conor Walsh}
}
@article {1661073,
	title = {Opportunities and challenges in the development of exoskeletons for locomotor assistance},
	journal = {Nature Biomedical Engineering},
	volume = {7},
	year = {2022},
	pages = {456{\textendash}472},
	abstract = {Exoskeletons can augment the performance of unimpaired users and restore movement in individuals with gait impairments. Knowledge of how users interact with wearable devices and of the physiology of locomotion have informed the design of rigid and soft exoskeletons that can specifically target a single joint or a single activity. In this Review, we highlight the main advances of the past two decades in exoskeleton technology and in the development of lower-extremity exoskeletons for locomotor assistance, discuss research needs for such wearable robots and the clinical requirements for exoskeleton-assisted gait rehabilitation, and outline the main clinical challenges and opportunities for exoskeleton technology.},
	url = {https://www.nature.com/articles/s41551-022-00984-1},
	author = {Christopher Siviy and Baker, Lauren M. and Quinlivan, Brendan T. and Franchino Porciuncula and Krithika Swaminathan and Louis N. Awad and Walsh, Conor J.}
}
@article {1656436,
	title = {Modulation of Achilles tendon force with load carriage and exosuit assistance},
	journal = {Science Robotics},
	volume = {7},
	number = {71},
	year = {2022},
	abstract = {Exosuits have the potential to assist locomotion in both healthy and pathological populations, but the effect of exosuit assistance on the underlying muscle-tendon tissue loading is not yet understood. In this study, we used shear wave tensiometers to characterize the modulation of Achilles tendon force with load carriage and exosuit assistance at the ankle. When walking (1.25 m/s) unassisted on a treadmill with load carriage weights of 15 and 30\% of body weight, peak Achilles tendon force increased by 11 and 23\%, respectively. Ankle exosuit assistance significantly reduced peak Achilles tendon force relative to unassisted, although the magnitude of change was variable across participants. Peak Achilles tendon force was significantly correlated with peak ankle torque for unassisted walking across load carriage conditions. However, when ankle plantarflexor assistance was applied, the relationship between peak tendon force and peak biological ankle torque was no longer significant. An outdoor pilot study was conducted in which a wearable shear wave tensiometer was used to measure Achilles tendon wave speed and compare across an array of assistance loading profiles. Reductions in tendon loading varied depending on the profile, highlighting the importance of in vivo measurements of muscle and tendon forces when studying and optimizing exoskeletons and exosuits.},
	url = {https://www.science.org/doi/10.1126/scirobotics.abq1514},
	author = {Dylan G. Schmitz and Richard W. Nuckols and Lee, Sangjun and Tunc Akbas and Krithika Swaminathan and Walsh, Conor J. and Darryl G. Thelen}
}
@article {1656057,
	title = {A continuous statistical-geometric framework for normative and impaired gaits},
	journal = {J. R. Soc. Interface},
	volume = {19},
	number = {196},
	year = {2022},
	abstract = {A quantitative analysis of human gait patterns in space{\textendash}time provides an opportunity to observe variability within and across individuals of varying motor capabilities. Impaired gait significantly affects independence and quality of life, and thus a large part of clinical research is dedicated to improving gait through rehabilitative therapies. Evaluation of these paradigms relies on understanding the characteristic differences in the kinematics and underlying biomechanics of impaired and unimpaired locomotion, which has motivated quantitative measurement and analysis of the gait cycle. Previous analysis has largely been limited to a statistical comparison of manually selected pointwise metrics identified through expert knowledge. Here, we use a recent statistical-geometric framework, elastic functional data analysis (FDA), to decompose kinematic data into continuous {\textquoteleft}amplitude{\textquoteright} (spatial) and {\textquoteleft}phase{\textquoteright} (temporal) components, which can then be integrated with established dimensionality reduction techniques. We demonstrate the utility of elastic FDA through two unsupervised applications to post-stroke gait datasets. First, we distinguish between unimpaired, paretic and non-paretic gait presentations. Then, we use FDA to reveal robust, interpretable groups of differential response to exosuit assistance. The proposed methods aim to benefit clinical practice for post-stroke gait rehabilitation, and more broadly, to automate the quantitative analysis of motion.},
	url = {https://royalsocietypublishing.org/doi/10.1098/rsif.2022.0402},
	author = {Krithika Swaminathan and Irina Tolkova and Lauren Baker and Dheepak Arumukhom Revi and Louis N. Awad and Walsh, Conor J. and Mahadevan, L.}
}
@article {1652534,
	title = {Soft robotic exosuit augmented high intensity gait training on stroke survivors: a pilot study},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {19},
	number = {51},
	year = {2022},
	abstract = {
	Background: Stroke is a leading cause of serious gait impairments and restoring walking ability is a major goal of physical therapy interventions. Soft robotic exosuits are portable, lightweight, and unobtrusive assistive devices designed to improve the mobility of post-stroke individuals through facilitation of more natural paretic limb function during walking training. However, it is unknown whether long-term gait training using soft robotic exosuits will clinically impact gait function and quality of movement post-stroke.



	Objective: The objective of this pilot study was to examine the therapeutic efects of soft robotic exosuit-augmented gait training on clinical and biomechanical gait outcomes in chronic post-stroke individuals.



	Methods: Five post-stroke individuals received high intensity gait training augmented with a soft robotic exosuit, delivered in 18 sessions over 6{\textendash}8 weeks. Performance based clinical outcomes and biomechanical gait quality parameters were measured at baseline, midpoint, and completion.



	Results: Clinically meaningful improvements were observed in walking speed (p \&lt; 0.05) and endurance (p \&lt; 0.01) together with other traditional gait related outcomes. The gait quality measures including hip (p \&lt; 0.01) and knee (p \&lt; 0.05) fexion/extension exhibited an increase in range of motion in a symmetric manner (p \&lt; 0.05). We also observed an increase in bilateral ankle angular velocities (p \&lt; 0.05), suggesting biomechanical improvements in walking function.



	Conclusions: The results in this study ofer preliminary evidence that a soft robotic exosuit can be a useful tool to augment high intensity gait training in a clinical setting. This study justifes more expanded research on soft exosuit technology with a larger post-stroke population for more reliable generalization.



	Trial registration This study is registered with ClinicalTrials.gov (ID: NCT04251091)



	Keywords: Exosuit, Soft robotics, High intensity gait training, Clinical outcomes, Gait quality, Stroke



	\&nbsp;

},
	url = {https://doi.org/10.1186/s12984-022-01034-2},
	author = {Sung Yul Shin and Kristen Hohl and Matt Gifhorn and Louis N. Awad and Walsh, Conor J. and Arun Jayaraman}
}
@article {1650964,
	title = {Towards Soft Wearable Strain Sensors for Muscle Activity Monitoring},
	journal = {IEEE Transactions on Neural Systems and Rehabilitation Engineering},
	volume = {30},
	year = {2022},
	pages = {2198-2206},
	abstract = {The force-generatingcapacity of skeletal muscle is an important metric in the evaluation and diagnosis of musculoskeletal health. Measuring changes in muscle force exertion is essential for tracking the progress of athletes during training, for evaluating patients{\textquoteright} recovery after muscle injury, and also for assisting the diagnosis of conditions such as muscular dystrophy, multiple sclerosis, or Parkinson{\textquoteright}s disease. Traditional hardware for strength evaluation requires technical training for operation, generates discrete time points for muscle assessment, and is implemented in controlled settings. The ability to continuously monitor muscle force without restricting the range of motion or adapting the exercise protocol to suit specific hardware would allow for a richer dataset that can help unlock critical features of muscle health and strength evaluation. In this paper, we employ wearable, ultra-sensitive soft strain sensors for tracking changes in muscle deformation during contractions. We demonstrate the sensors{\textquoteright} sensitivity to isometric contractions, as well as the sensors{\textquoteright} capacity to track changes in peak torque over the course of an isokinetic fatiguing protocol for the knee extensors. The wearable soft system was able to efficiently estimate peak joint torque reduction caused by muscle fatigue (mean NRMSE = 0.15{\textpm}0.03).},
	url = {https://ieeexplore.ieee.org/abstract/document/9849512},
	author = {Alvarez, Jonathan T. and Lucas F. Gerez and Oluwaseun A. Araromi and Jessica G. Hunter and Dabin K. Choe and Payne, Christopher J. and Wood, Robert J. and Walsh, Conor J.}
}
@article {1645384,
	title = {Reducing the energy cost of walking with low assistance levels through optimized hip flexion assistance from a soft exosuit},
	journal = {Nature - Scientific Reports},
	volume = {12},
	number = {11004},
	year = {2022},
	abstract = {As we age, humans see natural decreases in muscle force and power which leads to a slower, less efficient gait. Improving mobility for both healthy individuals and those with muscle impairments/weakness has been a goal for exoskeleton designers for decades. In this work, we discover that significant reductions in the energy cost required for walking can be achieved with almost 50\% less mechanical power compared to the state of the art. This was achieved by leveraging human-in-the-loop optimization to understand the importance of individualized assistance for hip flexion, a relatively unexplored joint motion. Specifically, we show that a tethered hip flexion exosuit can reduce the metabolic rate of walking by up to 15.2 {\textpm} 2.6\%, compared to locomotion with assistance turned off (equivalent to 14.8\% reduction compared to not wearing the exosuit). This large metabolic reduction was achieved with surprisingly low assistance magnitudes (average of 89\&nbsp;N, ~ 24\% of normal hip flexion torque). Furthermore, the ratio of metabolic reduction to the positive exosuit power delivered was 1.8 times higher than ratios previously found for hip extension and ankle plantarflexion. These findings motivated the design of a lightweight (2.31\&nbsp;kg) and portable hip flexion assisting exosuit, that demonstrated a 7.2 {\textpm} 2.9\% metabolic reduction compared to walking without the exosuit. The high ratio of metabolic reduction to exosuit power measured in this study supports previous simulation findings and provides compelling evidence that hip flexion may be an efficient joint motion to target when considering how to create practical and lightweight wearable robots to support improved mobility.},
	url = {https://www.nature.com/articles/s41598-022-14784-9},
	author = {Jinsoo Kim and Quinlivan, Brendan T. and Lou-Ana Deprey and Dheepak Arumukhom Revi and Asa Eckert-Erdheim and Patrick Murphy and Dorothy Orzel and Walsh, Conor J.}
}
@article {1645095,
	title = {A Soft Exosuit Assisting Hip Abduction for Knee Adduction Moment Reduction During Walking},
	journal = {IEEE Robotics and Automation Letters},
	volume = {7},
	number = {3},
	year = {2022},
	pages = {7439-7446},
	abstract = {The knee joint experiences significant torques in the frontal plane to keep the body upright during walking. Excessive loading over time can lead to knee osteoarthritis (OA), the progression of which is correlated with external knee adduction moment (KAM). In this paper, we present a wearable soft robotic exosuit that applies a hip abduction torque and evaluate its ability to reduce KAM. The exosuit uses a portable cable actuation system to generate torque when desired while remaining unrestrictive when unpowered. We explored five different force profiles on healthy participants (N=8) walking on an instrumented treadmill at 1.25 m/s. For each force profile, we tested two peak force levels: 15\% and 20\% of bodyweight. We observed KAM reductions with two of the five profiles. With Force Profile 2 (FP2), peak KAM was reduced by 9.61\% and impulse KAM by 12.76\%. With Force Profile 5 (FP5), we saw reductions of peak KAM by 6.14\% and impulse KAM by 21.09\%. These initial findings show that the device has the ability to change walking biomechanics in a consistent and potentially beneficial way.},
	url = {https://ieeexplore.ieee.org/document/9794926},
	author = {Hee Doo Yang and Myles Cooper and Eckert-Erdheim, Asa and Dorothy Orzel and Walsh, Conor J.}
}
@article {1636573,
	title = {An Expanding Foam-Fabric Orthopedic Cast},
	journal = {Advanced Materials Technologies},
	year = {2022},
	pages = {2101563},
	author = {Root, Samuel E. and Vanessa Sanchez and Tracz, Joanna A. and Preston, Daniel J. and Zvi, Yoav S. and Wang, Kemble and Walsh, Conor J. and Homer-Vanniasinkam, Shervanthi and George M. Whitesides}
}
@article {1665653,
	title = {Skeletal muscle regeneration with robotic actuation{\textendash}mediated clearance of neutrophils},
	journal = {Science Translational Medicine},
	volume = {13},
	number = {614},
	year = {2021},
	abstract = {Mechanical stimulation (mechanotherapy) can promote skeletal muscle repair, but a lack of reproducible protocols and mechanistic understanding of the relation between mechanical cues and tissue regeneration limit progress in this field. To address these gaps, we developed a robotic device equipped with real-time force control and compatible with ultrasound imaging for tissue strain analysis. We investigated the hypothesis that specific mechanical loading improves tissue repair by modulating inflammatory responses that regulate skeletal muscle regeneration. We report that cyclic compressive loading within a specific range of forces substantially improves functional recovery of severely injured muscle in mice. This improvement is attributable in part to rapid clearance of neutrophil populations and neutrophil-mediated factors, which otherwise may impede myogenesis. Insights from this work will help advance therapeutic strategies for tissue regeneration broadly.},
	url = {https://www.science.org/doi/10.1126/scitranslmed.abe8868},
	author = {Seo, Bo Ri and Payne, Christopher J. and Stephanie L. Mcnamara and Benjamin R. Freedman and Brian J. Kwee and Nam, Sungmin and Irene De Lazaro and Darnell, Max and Alvarez, Jonathan T. and Maxence O. Dellacherie and Vandenburgh, Herman H. and Walsh, Conor J. and Mooney, David J.}
}
@article {1630074,
	title = {Ankle resistance with a unilateral soft exosuit increases plantarflexor effort during pushoff in unimpaired individuals},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {18},
	number = {182},
	year = {2021},
	author = {Swaminathan, K. and Park, S. and Raza, F. and Porciuncula, F. and Lee, S. and Nuckols, R. and Awad, L. and C. Walsh}
}
@article {1622884,
	title = {Individualization of exosuit assistance based on measured muscle dynamics during versatile walking},
	journal = {Science Robotics},
	volume = {6},
	number = {60},
	year = {2021},
	url = {https://www.science.org/stoken/author-tokens/ST-156/full},
	author = {Nuckols, R. W. and Lee, S. and Swaminathan, K. and Orzel, D. and Howe, R.D. and C. J. Walsh}
}
@article {1618121,
	title = {Targeting Paretic Propulsion and Walking Speed With a Soft Robotic Exosuit: A Consideration-of-Concept Trial},
	journal = {Frontiers in Neurorobotics},
	volume = {15},
	number = {689577},
	year = {2021},
	author = {Porciuncula, F. and Baker, T. and Arumukhom Revi, D. and Bae, J. and Sloutsky, J. and Ellis, T. and C. Walsh and Awad, L.}
}
@article {1618036,
	title = {Estimation of Walking Speed and Its Spatiotemporal Determinants Using a Single Inertial Sensor Worn on the Thigh From Healthy to Hemiparetic Walking},
	journal = {Sensors},
	volume = {21},
	number = {6976},
	year = {2021},
	author = {Arumukhom Revi, D. and De Rossi, S. and C. Walsh and Awad, L.}
}
@article {1609806,
	title = {Real-time gait metric estimation for everyday gait training with wearable devices in people poststroke},
	journal = {Wearable Technologies},
	volume = {2},
	number = {e2},
	year = {2021},
	author = {Philipp Arens and Christopher Siviy and Jaehyun Bae and Dabin K. Choe and Nikos Karavas and Teresa Baker and Terry D. Ellis and Louis N. Awad and Walsh, Conor J.}
}
@article {1605051,
	title = {Importance of Preserved Tricuspid Valve Function for Effective Soft Robotic Augmentation of the Right Ventricle in Cases of Elevated Pulmonary Artery Pressure},
	journal = {Cardiovascular Engineering and Technology},
	year = {2021},
	url = {https://doi.org10.1007/s13239-021-00562-7},
	author = {Wamala, I. and Payne, C. J. and Saeed, M. Y. and D. Bautista-Salinas and D. Van Story and T. Thalhofer and Staffa, S. J. and Ghelani, S. J. and Nido, P.J. Del and C. J. Walsh and Vasilyev, N.V.}
}
@article {1604752,
	title = {Kinematics-Based Control of an Inflatable Soft Wearable Robot for Assisting the Shoulder of Industrial Workers},
	journal = {IEEE Robotics and Automation Letters},
	volume = {6},
	number = {2},
	year = {2021},
	pages = {2155-2162},
	abstract = {Recent developments in soft active wearable robotscan be used for upper extremity injury prevention for healthyindustrial workers with better comfort than rigid systems, but therehas not been control strategy proposals for such use cases. In this letter, we introduce a kinematics-based controller for an inflatable softwearable robot that provides assistance to the shoulder quickly andaccurately when needed during industrial use cases. Our approachis to use a state machine to classify user intent using shoulder andtrunk kinematics estimated with body-worn inertial measurementunits. We recruited eight participants to perform various taskscommon in the workplace and assessed the controller{\textquoteright}s intent classification accuracy and response times, by using the users{\textquoteright} reactionsto cues as their ground truth intentions. On average, we foundthat the kinematics controller had 99\% classification accuracy,and responded 0.8 seconds after the users reacted to the cue tobegin work and 0.5 seconds after the users reacted to a cue to stopthe task. In addition, we implemented an EMG-based controllerfor comparison, with state transitions determined by EMG-basedthresholds instead of kinematics. Compared to the EMG controller,the kinematics controller required similar time to detect the users{\textquoteright}intentions to stop overhead work but an additional 0.17 seconds onaverage for detecting users{\textquoteright} intentions to begin. Although slightlyslower, the kinematics controller still provided support prior tousers{\textquoteright} work initiations. We also implemented an online adaptivetuning algorithm for the kinematics controller to speed up response time while ensuring accuracy during offset transitions. Thisresearch paves the way for a further study of kinematics-basedcontroller in a mobile system in real work environments.},
	url = {https://ieeexplore.ieee.org/document/9361252/},
	author = {Zhou, Y. M. and Hohimer, C. and Proietti, T. and O{\textquoteright}Neill, C. and C. J. Walsh}
}
@article {1604751,
	title = {Sensing and Control of a Multi-Joint Soft Wearable Robot for Upper-Limb Assistance and Rehabilitation},
	journal = {IEEE Robotics and Automation Letters},
	volume = {6},
	number = {2},
	year = {2021},
	pages = {2381-2388},
	abstract = {In the field of wearable robotics, there has been increased interest in the creation of soft wearable robots to provideassistance and rehabilitation for those with physical impairments.Compared to traditional robots, these devices have the potential tobe fully portable and lightweight, a flexibility that may allow forincreased utilization time as well as enable use outside of a clinicalenvironment. In this letter, we present a textile-based multi-jointsoft wearable robot to assist the upper limb, in particular shoulderelevation and elbow extension. Before developing a portable fluidicsupply system, we leverage an off-board actuation system for powerand control, with the worn components weighting less than halfkilogram. We showed that this robot can be mechanically transparent when powered off, not restricting users from performingmovements associated with activities of daily living. Three IMUswere placed on the torso, upper arm and forearm to measure theshoulder and elbow kinematics. We found an average RMSE of\~{}5 degrees when compared to an optical motion capture system.We implemented dynamic Gravity Compensation (GC) and JointTrajectory Tracking (JTT) controllers that actively modulatedactuator pressure in response to IMU readings. The controller performances were evaluated in a study with eight healthy individuals.Using the GC controller, subject shoulder muscle activity decreasedwith increasing magnitude of assistance and for the JTT controller,we obtained low tracking errors (mean \~{}6 degrees RMSE). Futurework will evaluate the potential of the robot to assist with activitiesin post-stroke rehabilitation.},
	url = {https://ieeexplore.ieee.org/document/9360430},
	author = {Proietti, T. and O{\textquoteright}Neill, C. and Hohimer, C. J. and Nuckols, K. and Clarke, M. E. and Zhou, Y. M. and Lin, D. J. and C. J. Walsh}
}
@article {1582685,
	title = {Textile technology for soft robotic and autonomous garments},
	journal = {Advanced Functional Materials},
	volume = {31},
	number = {6},
	year = {2021},
	author = {Vanessa Sanchez and Conor Walsh and Wood, Robert}
}
@article {1618120,
	title = {Indirect measurement of anterior-posterior ground reaction forces using a minimal set of wearable inertial sensors: from healthy to hemiparetic walking},
	journal = {Journal of NeuroEngineering and Rehailitation},
	volume = {17},
	number = {82},
	year = {2020},
	author = {Arumukhom Revi, D. and Alvarez, A. and C. J. Walsh and De Rossi, S. and Awad, L.}
}
@article {1542457,
	title = {Ultra-sensitive and resilient compliant strain gauges for soft machines},
	journal = {Nature},
	volume = {587},
	year = {2020},
	pages = {219-224},
	abstract = {Soft machines are a promising design paradigm for human-centric devices and systems required to interact gently with their environment. To enable soft machines to respond intelligently to their surroundings, compliant sensory feedback mechanisms are needed. Specifically, soft alternatives to strain gauges{\textemdash}with high resolution at low strain (less than 5 per cent){\textemdash}could unlock promising new capabilities in soft systems. However, currently available sensing mechanisms typically possess either high strain sensitivity or high mechanical resilience, but not both. The scarcity of resilient and compliant ultra-sensitive sensing mechanisms has confined their operation to laboratory settings, inhibiting their widespread deployment. Here we present a versatile and compliant transduction mechanism for high-sensitivity strain detection with high mechanical resilience, based on strain-mediated contact in anisotropically resistive structures (SCARS). The mechanism relies upon changes in Ohmic contact between stiff, micro-structured, anisotropically conductive meanders encapsulated by stretchable films. The mechanism achieves high sensitivity, with gauge factors greater than 85,000, while being adaptable for use with high-strength conductors, thus producing sensors resilient to adverse loading conditions. The sensing mechanism also exhibits high linearity, as well as insensitivity to bending and twisting deformations{\textemdash}features that are important for soft device applications. To demonstrate the potential impact of our technology, we construct a sensor-integrated, lightweight, textile-based arm sleeve that can recognize gestures without encumbering the hand. We demonstrate predictive tracking and classification of discrete gestures and continuous hand motions via detection of small muscle movements in the arm. The sleeve demonstration shows the potential of the SCARS technology for the development of unobtrusive, wearable biomechanical feedback systems and human{\textendash}computer interfaces.},
	url = {https://www.nature.com/articles/s41586-020-2892-6},
	author = {Oluwaseun A. Araromi and Moritz A. Graule and Kristen L. Dorsey and Sam Castellanos and Jonathan R. Foster and Wen-Hao Hsu and Arthur E. Passy and Joost J. Vlassak and Weaver, James C. and Walsh, Conor J. and Wood, Robert J.}
}
@article {1518344,
	title = {Smart Thermally Actuating Textiles},
	journal = {Advanced Materials Technologies},
	year = {2020},
	author = {Vanessa Sanchez and Payne, Christopher J. and Preston, Daniel J. and Alvarez, Jonathan T. and Weaver, James C. and Atalay, Asli T. and Boyvat, Mustafa and Daniel M. Vogt and Wood, Robert J. and George M. Whitesides and Walsh, Conor J.}
}
@article {1511543,
	title = {Offline Assistance Optimization of a Soft Exosuit for Augmenting Ankle Power of Stroke Survivors During Walking},
	journal = {IEEE Robotics and Automation Letters},
	volume = {5},
	number = {2},
	year = {2020},
	author = {C. Siviy and Bae, J. and Baker, L. and Porciuncula, F. and Baker, T. and Ellis, T. D. and Awad, L. and C. J. Walsh}
}
@article {1506599,
	title = {Improving Grasp Function after Spinal Cord Injury with a Soft Robotic Glove},
	journal = {IEEE Transactions on Neural Systems and Rehabilitation Engineering},
	volume = {28},
	number = {6},
	year = {2020},
	pages = {1407-1415},
	author = {Correia, C. and Nuckols, K. and Wagner, D. and Zhou, Y. M. and Clarke, M. E. and Orzel, D. and Solinsky, R. and Paganoni, S. and C. J. Walsh}
}
@article {1506598,
	title = {Inflatable soft wearable robot for reducing therapist fatigue during upper extremity rehabilitation in severe stroke},
	journal = {IEEE Robotics and Automation Letters},
	volume = {5},
	number = {3},
	year = {2020},
	pages = {3899-3906},
	author = {O{\textquoteright}Neill, C. and Proietti, T. and Nuckols, K. and Clarke, M. E. and Hohimer, C. J. and Cloutier, A. and Lin, D. J. and C. J. Walsh}
}
@article {1506597,
	title = {Synchronization of a Soft Robotic Ventricular Assist Device to the Native Cardiac Rhythm Using an Epicardial Electrogram},
	journal = {ASME Journal of Medical Devices},
	year = {2020},
	author = {D. Bautista-Salinas and Hammer, P. E. and Payne, C. J. and Wamala, I. and Saeed, M. and T. Thalhofer and P. del Nido and C. J. Walsh}
}
@article {1506594,
	title = {A Hinge-Free, Non-Restrictive, Lightweight Tethered Exosuit for Knee Extension Assistance During Walking},
	journal = {IEEE Transactions on Medical Robotics and Bionics},
	year = {2020},
	author = {E. J. Park and Akbas, T. and Eckert-Erdheim, A. and Sloot, L. H. and Nuckols, R. W. and Orzel, D. and Schumm, L. and Ellis, T. D. and Awad, L. and C. J. Walsh}
}
@article {1506591,
	title = {Walking Faster and Farther With a Soft Robotic Exosuit: Implications for Post-Stroke Gait Assistance and Rehabilitation},
	journal = {IEEE Open Journal of Engineering in Medicine and Biology},
	volume = {1},
	year = {2020},
	pages = {108-115},
	author = {Awad, L. and Kudzia, P. and Revi, D. A. and Ellis, T. D. and C. J. Walsh}
}
@article {1576707,
	title = {The SDM Finger: Teaching engineering design through soft robotics},
	journal = {Science Scope},
	volume = {43},
	number = {4},
	year = {2019},
	pages = {14-21},
	author = {Sara Berndt and Maxwell Herman and Conor Walsh and Donal Holland}
}
@article {1470702,
	title = {Reducing the metabolic rate of walking and running with a versatile, portable exosuit},
	journal = {Science},
	volume = {365},
	number = {6454},
	year = {2019},
	pages = {668-672},
	abstract = {Walking and running have fundamentally different biomechanics, which makes developing devices that assist both gaits challenging. We show that a portable exosuit that assists hip extension can reduce the metabolic rate of treadmill walking at 1.5 meters per second by 9.3\% and that of running at 2.5 meters per second by 4.0\% compared with locomotion without the exosuit. These reduction magnitudes are comparable to the effects of taking off 7.4 and 5.7 kilograms during walking and running, respectively, and are in a range that has shown meaningful athletic performance changes. The exosuit automatically switches between actuation profiles for both gaits, on the basis of estimated potential energy fluctuations of the wearer{\textquoteright}s center of mass. Single-participant experiments show that it is possible to reduce metabolic rates of different running speeds and uphill walking, further demonstrating the exosuit{\textquoteright}s versatility.},
	url = {http://science.sciencemag.org/cgi/content/full/365/6454/668?ijkey=d9y.Kwfg4guac\&keytype=ref\&siteid=sci},
	author = {Jinsoo Kim and Lee, Giuk and Roman Heimgartner and Dheepak Arumukhom Revi and Nikos Karavas and Danielle Nathanson and Ignacio Galiana and Eckert-Erdheim, Asa and Patrick Murphy and David Perry and Nicolas Menard and Dabin Kim Choe and Philippe Malcolm and Walsh, Conor J.}
}
@article {1468689,
	title = {Gait Initiation of New Walkers and the Adult{\textquoteright}s Role in Regulating Directionality of the Child{\textquoteright}s Body Motion},
	journal = {Journal of Motor Learning and Development},
	volume = {7},
	number = {1},
	year = {2019},
	pages = {35-48},
	author = {Wen-Hao Hsu and Park, Evelyn J. and Miranda, Daniel L. and Hani M. Sallum and Walsh, Conor J. and Goldfield, Eugene C.}
}
@article {1447460,
	title = {Metabolic cost adaptations during training with a soft exosuit assisting the hip joint},
	journal = {Scientific Reports},
	year = {2019},
	author = {Panizzolo, F. and Freisinger, G. and Karavas, N. and Eckert-Erdheim, A. and C. Siviy and Long, A. and Zifchock, R. and LaFiandra, M. and C. Walsh}
}
@article {1444817,
	title = {A soft ring oscillator},
	journal = {Science Robotics},
	volume = {4},
	number = {31},
	year = {2019},
	author = {Preston, D.J. and Jiang, H.J. and V. Sanchez and Rothemund, P. and Rawson, J. and Nemitz, M.P. and W. Lee and Z. Suo and C. J. Walsh and Whitesides, G. M.}
}
@article {1440535,
	title = {Robotic Artificial Muscles: Current Progress and Future Perspectives},
	journal = {IEEE Transaction on Robitics},
	year = {2019},
	pages = {1-21},
	author = {Zhang, J. and J. Sheng and O{\textquoteright}Neill, C. and C. Walsh and R. Wood and J. Ryu and J. Desai and M. Yip}
}
@article {1436076,
	title = {Simulating Hemiparetic Gait in Healthy Subjects using TPAD with a Closed-loop Controller},
	journal = {IEEE Transactions on Neural Systems and Rehabilitation Engineering},
	volume = {27},
	number = {5},
	year = {2019},
	pages = {974-983},
	author = {Kang, J. and Ghonasgi, K. and C. Walsh and Agrawal, S.}
}
@article {1414043,
	title = {Sew-free anisotropic textile composites for rapid design and manufacturing of soft wearable robots},
	journal = {Extreme Mechanics Letters},
	volume = {27},
	year = {2019},
	pages = {52-58},
	url = {https://authors.elsevier.com/c/1YRqy8MuOgzw2z},
	author = {F. Connolly and D. A. Wagner and C. J. Walsh and K. Bertoldi}
}
@article {1407617,
	title = {Comparison of the human-exosuit interaction using ankle moment and ankle positive power inspired walking assistance},
	journal = {Journal of Biomechanics},
	volume = {83},
	number = {23},
	year = {2019},
	pages = {76-84},
	author = {Grimmer, M. and B. T. Quinlivan and Lee, S. and Malcolm, P. and D. M. Rossi and C. Siviy and C. J. Walsh}
}
@article {1406539,
	title = {Mobility related physical and functional losses due to aging and disease - a motivation for lower limb exoskeletons},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {16},
	number = {1},
	year = {2019},
	author = {Grimmer, M. and Riener, R. and C. J. Walsh and Seyfarth, A.}
}
@article {1423927,
	title = {Autonomous multi-joint soft exosuit with augmentation-power-based control parameter tuning reduces energy cost of loaded walking},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {15},
	number = {1},
	year = {2018},
	pages = {66},
	author = {Lee, S. and Kim, J. and Baker, L. and Long, A. and Karavas, N. and Menard, N. and Galiana, I. and C. Walsh}
}
@article {1406493,
	title = {The Development and Evaluation of DEFT, a Web-Based Tool for Engineering Design Education},
	journal = {IEEE Transaction on Learning Technologies},
	volume = {11},
	number = {4},
	year = {2018},
	author = {Moyne, M. and M. Herman and Gajos, K. Z. and C. Walsh and D. P. Holland}
}
@article {1333841,
	title = {Wearable movement sensors for rehabilitation: A focused review of technological and clinical advances},
	journal = {PM\&R},
	volume = {10},
	number = {9},
	year = {2018},
	pages = {S220-232},
	author = {Franchino Porciuncula and Anna Virginia Roto and Deepak Kumar and Irene Davis and Serge Roy and Walsh, Conor J. and Louis N. Awad}
}
@article {1322040,
	title = {Exploiting Textile Mechanical Anisotropy for Fabric-Based Pneumatic Actuators},
	journal = {Soft Robotics},
	year = {2018},
	author = {Cappello, Leonardo and Galloway, Kevin C. and Siddharth Sanan and Wagner, Diana A. and Granberry, Rachael and Engelhardt, Sven and Haufe, Florian L. and Peisner, Jeffrey D. and Walsh, Conor J.}
}
@article {Cappello2018,
	title = {Assisting hand function after spinal cord injury with a fabric-based soft robotic glove},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {15},
	number = {1},
	year = {2018},
	month = {Jun},
	pages = {59},
	abstract = {Spinal cord injury is a devastating condition that can dramatically impact hand motor function. Passive and active assistive devices are becoming more commonly used to enhance lost hand strength and dexterity. Soft robotics is an emerging discipline that combines the classical principles of robotics with soft materials and could provide a new class of active assistive devices. Soft robotic assistive devices enable a human-robot interaction facilitated by compliant and light-weight structures. The scope of this work was to demonstrate that a fabric-based soft robotic glove can effectively assist participants affected by spinal cord injury in manipulating objects encountered in daily living.},
	issn = {1743-0003},
	doi = {10.1186/s12984-018-0391-x},
	url = {https://doi.org/10.1186/s12984-018-0391-x},
	author = {Cappello, Leonardo and Meyer, Jan T. and Galloway, Kevin C. and Peisner, Jeffrey D. and Granberry, Rachael and Wagner, Diana A. and Engelhardt, Sven and Paganoni, Sabrina and Walsh, Conor J.}
}
@article {1316159,
	title = {Sustained release of targeted cardiac therapy with a replenishable implantable epicardial reservoir},
	journal = {Nature Biomedical Engineering},
	volume = {2},
	year = {2018},
	pages = {416-428},
	author = {Whyte, W. and Roche, E. and Varela, C. and Mendez, K. and Islam, S. and O{\textquoteright}Neill, H. and Weafer, F. and Shirazi, R. and Weaver, J. and Vasilyev, N. and McHugh, P. and Murphy, B. and Duffy, G. and C. Walsh and Mooney, D.}
}
@article {Horvath2018,
	title = {Towards Alternative Approaches for Coupling of a Soft Robotic Sleeve to the Heart},
	journal = {Annals of Biomedical Engineering},
	year = {2018},
	month = {May},
	abstract = {Efficient coupling of soft robotic cardiac assist devices to the external surface of the heart is crucial to augment cardiac function and represents a hurdle to translation of this technology. In this work, we compare various fixation strategies for local and global coupling of a direct cardiac compression sleeve to the heart. For basal fixation, we find that a sutured Velcro band adheres the strongest to the epicardium. Next,\&nbsp;we demonstrate that a mesh-based sleeve coupled to the myocardium improves function in an acute porcine heart failure model. Then, we analyze the biological integration of global interface material candidates (medical mesh and silicone) in a healthy and infarcted murine model and show that a mesh interface yields superior mechanical coupling via pull-off force, histology, and microcomputed tomography. These results can inform the design of a therapeutic approach where a mesh-based soft robotic DCC is implanted, allowed to biologically integrate with the epicardium, and actuated for active assistance at a later timepoint. This strategy may result in more efficient coupling of extracardiac sleeves to heart tissue, and lead to increased augmentation of heart function in end-stage heart failure patients.},
	issn = {1573-9686},
	doi = {10.1007/s10439-018-2046-2},
	url = {https://doi.org/10.1007/s10439-018-2046-2},
	author = {Markus A. Horvath and Varela, Claudia E. and Dolan, Eimear B. and Whyte, William and Monahan, David S. and Payne, Christopher J. and Wamala, Isaac A. and Nikolay V. Vasilyev and Pigula, Frank A. and Mooney, David J. and Walsh, Conor J. and Duffy, Garry P. and Roche, Ellen T.}
}
@article {1309939,
	title = {Human-in-the-loop development of soft wearable robots},
	journal = {Nature Review Materials},
	volume = {3},
	year = {2018},
	pages = {78-80},
	abstract = {The field of soft wearable robotics offers the opportunity to wear robots like clothes to assist the movement of specific body parts or to endow the body with functionalities. Collaborative efforts of materials, apparel and robotics science have already led to the development of wearable technologies for physical therapy. Optimizing the human{\textendash}robot system by human-in-the-loop approaches will pave the way for personalized soft wearable robots for a variety of applications.},
	url = {http://www.nature.com/articles/s41578-018-0011-1.epdf?shared_access_token=F0-xM2SjDIHcKgKmlQQkSNRgN0jAjWel9jnR3ZoTv0PWvMNraNIOR4P7Uc4-spc-r2a3hHSfoMXKXnKoqEgcIkD3hAKMnfEtyKW5SyJu3y-VGhK9i48sM40U88xSuy8Huy0izyof-859Tx03q-uwnzNXVq6uboJiQRYPkT8JcTc\%3D},
	author = {Conor J Walsh}
}
@article {doi:10.1080/03043797.2018.1463196,
	title = {A qualitative investigation of design knowledge reuse in project-based mechanical design courses},
	journal = {European Journal of Engineering Education},
	year = {2018},
	pages = {1-16},
	publisher = {Taylor \& Francis},
	doi = {10.1080/03043797.2018.1463196},
	url = {https://doi.org/10.1080/03043797.2018.1463196},
	author = {Holland, D{\'o}nal P. and Walsh, Conor J. and Gareth J. Bennett}
}
@article {1308003,
	title = {Growing the Soft Robotics Community Through Knowledge-Sharing Initiatives},
	journal = {Soft Robotics},
	volume = {5},
	number = {2},
	year = {2018},
	pages = {119-121},
	url = {https://doi.org/10.1089/soro.2018.29013.dph},
	author = {Holland, D. and Berndt, S. and M. Herman and C. Walsh}
}
@article {8314622,
	title = {Wearable Robotics for Motion Assistance and Rehabilitation [TC Spotlight]},
	journal = {IEEE Robotics Automation Magazine},
	volume = {25},
	number = {1},
	year = {2018},
	month = {March},
	pages = {19-28},
	issn = {1070-9932},
	doi = {10.1109/MRA.2017.2787222},
	author = {S. Mohammed and J. C. Moreno and T. Sugar and Y. Hasegawa and N. Vitiello and Wang, Q. and C. J. Walsh}
}
@article {8003473,
	title = {Distal Proprioceptive Sensor for Motion Feedback in Endoscope-Based Modular Robotic Systems},
	journal = {IEEE Robotics and Automation Letters},
	volume = {3},
	number = {1},
	year = {2018},
	month = {Jan},
	pages = {171-178},
	keywords = {actuator module, actuators, angle measurements, angle of articulation, angular measurement, closed loop systems, closed-loop position control, Couplings, distal proprioceptive angle sensor, distal robotic modules, endoscope-based modular robotic systems, Endoscopes, environmental irradiance measurements, Feedback, flexible robots, fully deployable endoscope-based robotic modules, fully distal closed-loop control, kinematic linkage, Kinematics, light intensity modulation, linear regression techniques, mechanism design, Medical robotics, Medical Robots and Systems, micromechanical devices, motion feedback, patient treatment, position control, printed-circuit MEMS, real-time proprioceptive feedback, Regression Analysis, Robot kinematics, Robot sensing systems, temperature measurement, temperature measurements, therapeutic endoscopy},
	doi = {10.1109/LRA.2017.2737042},
	author = {J. Gafford and H. Aihara and C. Thompson and R. Wood and C. Walsh}
}
@article {Baejeb.168815,
	title = {Biomechanical mechanisms underlying exosuit-induced improvements in walking economy after stroke},
	journal = {Journal of Experimental Biology},
	year = {2018},
	publisher = {The Company of Biologists Ltd},
	abstract = {{Stroke-induced hemiparetic gait is characteristically asymmetric and metabolically expensive. Weakness and impaired control of the paretic ankle contribute to reduced forward propulsion and ground clearance{\textemdash}walking subtasks critical for safe and efficient locomotion. Targeted gait interventions that improve paretic ankle function after stroke are therefore warranted. We have developed textile-based, soft wearable robots that transmit mechanical power generated by off-board or body-worn actuators to the paretic ankle using Bowden cables (soft exosuits) and have demonstrated the exosuits can overcome deficits in paretic limb forward propulsion and ground clearance, ultimately reducing the metabolic cost of hemiparetic walking. This study elucidates the biomechanical mechanisms underlying exosuit-induced reductions in metabolic power. We evaluated the relationships between exosuit-induced changes in the body center of mass (COM) power generated by each limb, individual joint powers, and metabolic power. Compared to walking with an exosuit unpowered, exosuit assistance produced more symmetrical COM power generation during the critical period of the step-to-step transition (22.4{\textpm}6.4\% more symmetric). Changes in individual limb COM power were related to changes in paretic (R2= 0.83},
	issn = {0022-0949},
	doi = {10.1242/jeb.168815},
	url = {http://jeb.biologists.org/content/early/2018/01/18/jeb.168815},
	author = {Jaehyun Bae and Louis N. Awad and Long, Andrew and O{\textquoteright}Donnell, Kathleen and Hendron, Katy and Kenneth G. Holt and Terry D. Ellis and Walsh, Conor J.}
}
@article {1298556,
	title = {Human-in-the-loop optimization of hip assistance with a soft exosuit during walking},
	journal = {Science Robotics},
	volume = {3},
	number = {15},
	year = {2018},
	pages = {eaar5438},
	abstract = {Wearable robotic devices have been shown to substantially reduce the energy expenditure of human walking. However, response variance between participants for fixed control strategies can be high, leading to the hypothesis that individualized controllers could further improve walking economy. Recent studies on human-in-the-loop (HIL) control optimization have elucidated several practical challenges, such as long experimental protocols and low signal-to-noise ratios. Here, we used Bayesian optimization{\textemdash}an algorithm well suited to optimizing noisy performance signals with very limited data{\textemdash}to identify the peak and offset timing of hip extension assistance that minimizes the energy expenditure of walking with a textile-based wearable device. Optimal peak and offset timing were found over an average of 21.4 {\textpm} 1.0 min and reduced metabolic cost by 17.4 {\textpm} 3.2\% compared with walking without the device (mean {\textpm} SEM), which represents an improvement of more than 60\% on metabolic reduction compared with state-of-the-art devices that only assist hip extension. In addition, our results provide evidence for participant-specific metabolic distributions with respect to peak and offset timing and metabolic landscapes, lending support to the hypothesis that individualized control strategies can offer substantial benefits over fixed control strategies. These results also suggest that this method could have practical impact on improving the performance of wearable robotic devices.},
	url = {http://robotics.sciencemag.org/content/3/15/eaar5438.full},
	author = {Ye Ding and Kim, Myunghee and Kuindersma, S. and Walsh, Conor J.}
}
@article {Payneeaan6736,
	title = {Soft robotic ventricular assist device with septal bracing for therapy of heart failure},
	journal = {Science Robotics},
	volume = {2},
	number = {12},
	year = {2017},
	publisher = {Science Robotics},
	abstract = {Previous soft robotic ventricular assist devices have generally targeted biventricular heart failure and have not engaged the interventricular septum that plays a critical role in blood ejection from the ventricle. We propose implantable soft robotic devices to augment cardiac function in isolated left or right heart failure by applying rhythmic loading to either ventricle. Our devices anchor to the interventricular septum and apply forces to the free wall of the ventricle to cause approximation of the septum and free wall in systole and assist with recoil in diastole. Physiological sensing of the native hemodynamics enables organ-in-the-loop control of these robotic implants for fully autonomous augmentation of heart function. The devices are implanted on the beating heart under echocardiography guidance. We demonstrate the concept on both the right and the left ventricles through in vivo studies in a porcine model. Different heart failure models were used to demonstrate device function across a spectrum of hemodynamic conditions associated with right and left heart failure. These acute in vivo studies demonstrate recovery of blood flow and pressure from the baseline heart failure conditions. Significant reductions in diastolic ventricle pressure were also observed, demonstrating improved filling of the ventricles during diastole, which enables sustainable cardiac output.},
	doi = {10.1126/scirobotics.aan6736},
	url = {http://robotics.sciencemag.org/content/2/12/eaan6736},
	author = {Payne, Christopher J. and Wamala, Isaac and Bautista-Salinas, Daniel and Saeed, Mossab and Van Story, David and Thalhofer, Thomas and Markus A. Horvath and Abah, Colette and Pedro J. del Nido and Walsh, Conor J. and Nikolay V. Vasilyev}
}
@article {1258411,
	title = {Highly Sensitive Capacitive-Based Soft Pressure Sensor Based on Conductive Fabric and Micro-porous Dielectric Layer},
	journal = {Advanced Materials Technologies},
	year = {2017},
	abstract = {In this paper, the design and manufacturing of a highly sensitive capacitive-based soft pressure sensor for wearable electronics applications are presented. Toward this aim, two types of soft conductive fabrics (knitted and woven), as well as two types of sacrificial particles (sugar granules and salt crystals) to create micropores within the dielectric layer of the capacitive sensor are evaluated, and the combined effects on the sensor{\textquoteright}s overall performance are assessed. It is found that a combination of the conductive knit electrode and higher dielectric porosity (generated using the larger sugar granules) yields higher sensitivity (121 {\texttimes} 10-4\&nbsp;kPa-1) due to greater compressibility and the formation of air gaps between silicone elastomer and conductive knit electrode among the other design considerations in this study. As a practical demonstration, the capacitive sensor is embedded into a textile glove for grasp motion monitoring during activities of daily living.},
	url = {http://onlinelibrary.wiley.com/doi/10.1002/admt.201700237/abstract?systemMessage=Wiley+Online+Library+usage+report+download+page+will+be+unavailable+on+Friday+24th+November+2017+at+21\%3A00+EST+\%2F+02.00+GMT+\%2F+10\%3A00+SGT+\%28Saturday+25th+Nov+for+SGT+},
	author = {Ozgur Atalay and Asli Atalay and Joshua Gafford and Conor J Walsh}
}
@article {Panizzolo4169,
	title = {Lower limb biomechanical analysis during an unanticipated step on a bump reveals specific adaptations of walking on uneven terrains},
	journal = {Journal of Experimental Biology},
	volume = {220},
	number = {22},
	year = {2017},
	pages = {4169{\textendash}4176},
	publisher = {The Company of Biologists Ltd},
	abstract = {Although it is clear that walking over different irregular terrain is associated with altered biomechanics, there is little understanding of how we quickly adapt to unexpected variations in terrain. This study aims to investigate which adaptive strategies humans adopt when performing an unanticipated step on an irregular surface, specifically a small bump. Nine healthy male participants walked at their preferred walking speed along a straight walkway during five conditions: four involving unanticipated bumps of two different heights, and one level walking condition. Muscle activation of eight lower limb muscles and three-dimensional gait analysis were evaluated during these testing conditions. Two distinct adaptive strategies were found, which involved no significant change in total lower limb mechanical work or walking speed. An ankle-based strategy was adopted when stepping on a bump with the forefoot, whereas a hip-based strategy was preferred when stepping with the rearfoot. These strategies were driven by a higher activation of the plantarflexor muscles (6{\textendash}51\%), which generated a higher ankle joint moment during the forefoot conditions and by a higher activation of the quadriceps muscles (36{\textendash}93\%), which produced a higher knee joint moment and hip joint power during the rearfoot conditions. These findings provide insights into how humans quickly react to unexpected events and could be used to inform the design of adaptive controllers for wearable robots intended for use in unstructured environments that can provide optimal assistance to the different lower limb joints.},
	issn = {0022-0949},
	doi = {10.1242/jeb.161158},
	url = {http://jeb.biologists.org/content/220/22/4169},
	author = {Panizzolo, Fausto A. and Lee, Sangjun and Taira Miyatake and Rossi, Denise Martineli and Christopher Siviy and Jozefien Speeckaert and Ignacio Galiana and Walsh, Conor J.}
}
@article {1188321,
	title = {An Implantable Extracardiac Soft Robotic Device for the Failing Heart: Mechanical Coupling and Synchronization},
	journal = {Soft Robotics},
	volume = {4},
	number = {3},
	year = {2017},
	pages = {241-250},
	abstract = {Soft robotic devices have significant potential for medical device applications that warrant safe synergistic interaction with humans. This article describes the optimization of an implantable soft robotic system for heart failure whereby soft actuators wrapped around the ventricles are programmed to contract and relax in synchrony with the beating heart. Elastic elements integrated into the soft actuators provide recoiling function so as to aid refilling during the diastolic phase of the cardiac cycle. Improved synchronization with the biological system is achieved by incorporating the native ventricular pressure into the control system to trigger assistance and synchronize the device with the heart. A three-state electro-pneumatic valve configuration allows the actuators to contract at different rates to vary contraction patterns. An in vivo study was performed to test three hypotheses relating to mechanical coupling and temporal synchronization of the actuators and heart. First, that adhesion of the actuators to the ventricles improves cardiac output. Second, that there is a contraction{\textendash}relaxation ratio of the actuators which generates optimal cardiac output. Third, that the rate of actuator contraction is a factor in cardiac output.},
	url = {https://doi.org/10.1089/soro.2016.0076},
	author = {Payne, Christopher J. and Wamala, Isaac and Abah, Colette and Thalhofer, Thomas and Saeed, Mossab and Bautista-Salinas, Daniel and Markus A. Horvath and Nikolay V. Vasilyev and Roche, Ellen T. and Pigula, Frank A. and Walsh, Conor J.}
}
@article {10.1371/journal.pone.0184054,
	title = {Human-in-the-loop Bayesian optimization of wearable device parameters},
	journal = {PLOS ONE},
	volume = {12},
	number = {9},
	year = {2017},
	month = {19 Sep, 2017},
	pages = {1-15},
	publisher = {Public Library of Science},
	abstract = {The increasing capabilities of exoskeletons and powered prosthetics for walking assistance have paved the way for more sophisticated and individualized control strategies. In response to this opportunity, recent work on human-in-the-loop optimization has considered the problem of automatically tuning control parameters based on realtime physiological measurements. However, the common use of metabolic cost as a performance metric creates significant experimental challenges due to its long measurement times and low signal-to-noise ratio. We evaluate the use of Bayesian optimization{\textemdash}a family of sample-efficient, noise-tolerant, and global optimization methods{\textemdash}for quickly identifying near-optimal control parameters. To manage experimental complexity and provide comparisons against related work, we consider the task of minimizing metabolic cost by optimizing walking step frequencies in unaided human subjects. Compared to an existing approach based on gradient descent, Bayesian optimization identified a near-optimal step frequency with a faster time to convergence (12 minutes, p \&lt; 0.01), smaller inter-subject variability in convergence time ({\textpm} 2 minutes, p \&lt; 0.01), and lower overall energy expenditure (p \&lt; 0.01).},
	doi = {10.1371/journal.pone.0184054},
	url = {https://doi.org/10.1371/journal.pone.0184054},
	author = {Kim, Myunghee and Ye Ding and Philippe Malcolm and Jozefien Speeckaert and Siviy, Christoper J. and Walsh, Conor J. and Scott Kuindersma}
}
@article {1132816,
	title = {Distal Proprioceptive Sensor for Motion Feedback in Endoscope-Based Modular Robotic Systems},
	journal = {IEEE Robotics and Automation Letters},
	volume = {PP},
	year = {2017},
	abstract = {Modular robotic systems that integrate with commercially-available endoscopic equipment have the potential to improve the standard-of-care in therapeutic endoscopy by granting clinicians with capabilities not present in commercial tools, such as precision dexterity and motion sensing. With the desire to integrate both sensing and actuation distally for closed-loop position control in fully-deployable, endoscope-based robotic modules, commercial sensor and actuator options that acquiesce to the strict form-factor requirements are sparse or nonexistent. Herein we describe a proprioceptive angle sensor for potential closed-loop position control applications in distal robotic modules. Fabricated monolithically using printed-circuit MEMS, the sensor employs a kinematic linkage and the principle of light intensity modulation to sense the angle of articulation with a high degree of fidelity. On-board temperature and environmental irradiance measurements, coupled with linear regression techniques, provide robust angle measurements that are insensitive to environmental disturbances. The sensor is capable of measuring +/-45 degrees of articulation with an RMS error of 0.98 degrees. An integrated demonstration shows that the sensor can give real-time proprioceptive feedback when coupled with an actuator module, opening up the possibility of fully-distal closed-loop control.},
	url = {https://doi.org/10.1109/LRA.2017.2737042},
	author = {Joshua B. Gafford and Aihara, Hiroyuki and Thompson, Christopher and Wood, Robert J. and Walsh, Conor J.}
}
@article {Awadeaai9084,
	title = {A soft robotic exosuit improves walking in patients after stroke},
	journal = {Science Translational Medicine},
	volume = {9},
	number = {400},
	year = {2017},
	pages = {eaai9084},
	publisher = {American Association for the Advancement of Science},
	abstract = {
	Passive assistance devices such as canes and braces are often used by people after stroke, but mobility remains limited for some patients. Awad et al. studied the effects of active assistance (delivery of supportive force) during walking in nine patients in the chronic phase of stroke recovery. A soft robotic exosuit worn on the partially paralyzed lower limb reduced interlimb propulsion asymmetry, increased ankle dorsiflexion, and reduced the energy required to walk when powered on during treadmill and overground walking tests. The exosuit could be adjusted to deliver supportive force during the early or late phase of the gait cycle depending on the patient{\textquoteright}s needs. Although long-term therapeutic studies are necessary, the immediate improvement in walking performance observed using the powered exosuit makes this a promising approach for neurorehabilitation.



	Stroke-induced hemiparetic gait is characteristically slow and metabolically expensive. Passive assistive devices such as ankle-foot orthoses are often prescribed to increase function and independence after stroke; however, walking remains highly impaired despite{\textemdash}and perhaps because of{\textemdash}their use. We sought to determine whether a soft wearable robot (exosuit) designed to supplement the paretic limb{\textquoteright}s residual ability to generate both forward propulsion and ground clearance could facilitate more normal walking after stroke. Exosuits transmit mechanical power generated by actuators to a wearer through the interaction of garment-like, functional textile anchors and cable-based transmissions. We evaluated the immediate effects of an exosuit actively assisting the paretic limb of individuals in the chronic phase of stroke recovery during treadmill and overground walking. Using controlled, treadmill-based biomechanical investigation, we demonstrate that exosuits can function in synchrony with a wearer{\textquoteright}s paretic limb to facilitate an immediate 5.33 {\textpm} 0.91{\textdegree} increase in the paretic ankle{\textquoteright}s swing phase dorsiflexion and 11 {\textpm} 3\% increase in the paretic limb{\textquoteright}s generation of forward propulsion (P \&lt; 0.05). These improvements in paretic limb function contributed to a 20 {\textpm} 4\% reduction in forward propulsion interlimb asymmetry and a 10 {\textpm} 3\% reduction in the energy cost of walking, which is equivalent to a 32 {\textpm} 9\% reduction in the metabolic burden associated with poststroke walking. Relatively low assistance (\&nbsp;12\% of biological torques) delivered with a lightweight and nonrestrictive exosuit was sufficient to facilitate more normal walking in ambulatory individuals after stroke. Future work will focus on understanding how exosuit-induced improvements in walking performance may be leveraged to improve mobility after stroke.

},
	issn = {1946-6234},
	doi = {10.1126/scitranslmed.aai9084},
	url = {http://stm.sciencemag.org/cgi/content/full/9/400/eaai9084?ijkey=K/pmOVs/Os2Xo\&keytype=ref\&siteid=scitransmed},
	author = {Louis N. Awad and Jaehyun Bae and O{\textquoteright}Donnell, Kathleen and De Rossi, Stefano M.M. and Hendron, Kathryn and Sloot, Lizeth H. and Kudzia, Pawel and Stephen Allen and Kenneth G. Holt and Terry D. Ellis and Walsh, Conor J.}
}
@article {awad2017reducing,
	title = {Reducing Circumduction and Hip Hiking During Hemiparetic Walking Through Targeted Assistance of the Paretic Limb Using a Soft Robotic Exosuit.},
	journal = {American Journal of Physical Medicine \& Rehabilitation},
	year = {2017},
	publisher = {LWW},
	abstract = {
	ObjectiveThe aim of the study was to evaluate the effects on common poststroke gait compensations of a soft wearable robot (exosuit) designed to assist the paretic limb during hemiparetic walking.



	DesignA single-session study of eight individuals in the chronic phase of stroke recovery was conducted. Two testing conditions were compared: walking with the exosuit powered versus walking with the exosuit unpowered. Each condition was 8 minutes in duration.



	ResultsCompared with walking with the exosuit unpowered, walking with the exosuit powered resulted in reductions in hip hiking (27 [6\%], P = 0.004) and circumduction (20 [5\%], P = 0.004). A relationship between changes in knee flexion and changes in hip hiking was observed (Pearson r = -0.913, P \&lt; 0.001). Similarly, multivariate regression revealed that changes in knee flexion (β = -0.912, P = 0.007), but not ankle dorsiflexion (β = -0.194, P = 0.341), independently predicted changes in hip hiking (R2= 0.87, F(2, 4) = 13.48, P = 0.017).



	ConclusionsExosuit assistance of the paretic limb during walking produces immediate changes in the kinematic strategy used to advance the paretic limb. Future work is necessary to determine how exosuit-induced reductions in paretic hip hiking and circumduction during gait training could be leveraged to facilitate more normal walking behavior during unassisted walking.

},
	url = {https://doi.org/10.1097/PHM.0000000000000800},
	author = {Louis N. Awad and Jaehyun Bae and Kudzia, Pawel and Long, Andrew and Hendron, Kathryn and Kenneth G. Holt and Kathleen O{\textquoteright}Donnell and Terry D. Ellis and Conor J Walsh}
}
@article {ADMT:ADMT201700135,
	title = {An Additive Millimeter-Scale Fabrication Method for Soft Biocompatible Actuators and Sensors},
	journal = {Advanced Materials Technologies},
	year = {2017},
	abstract = {A hybrid manufacturing paradigm is introduced that combines pop-up book microelectromechanical systems (MEMS) manufacturing with soft-lithographic techniques to produce millimeter-scale mechanisms with embedded sensing and user-defined distributed compliance. This method combines accuracy, flexibility in material selection, scalability, and topological complexity with soft, biocompatible materials and microfluidics, paving the way for applications of soft fluid-powered biomedical robotics. This paper proposes two classes of fully soft fluidic microactuators and two integration strategies to demonstrate the hybrid soft pop-up actuators. Fatigue properties, blocked torque, maximum deflection, stiffness, and maximum speed are analyzed and the performance of the hybrid mechanisms is compared to their fully soft counterparts. The manufacturing approach allows integrating capacitive sensing elements in the mechanisms to achieve proprioceptive actuation. Multiple hybrid soft pop-up actuators are combined into a multiarticulated robotic arm that is integrated with current flexible endoscopes to improve distal dexterity and enable tissue retraction in an ex vivo proof of concept experiment.},
	keywords = {actuators, advanced manufacturing, sensors, soft robotics, surgical robotics},
	issn = {2365-709X},
	doi = {10.1002/admt.201700135},
	url = {http://dx.doi.org/10.1002/admt.201700135},
	author = {Sheila Russo and Ranzani, Tommaso and Walsh, Conor J. and Wood, Robert J.}
}
@article {1115171,
	title = {Continuous sweep versus discrete step protocols for studying effects of wearable robot assistance magnitude},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {14},
	number = {1},
	year = {2017},
	month = {July 12},
	pages = {72},
	type = {journal article},
	abstract = {
	BackgroundDifferent groups developed wearable robots for walking assistance, but there is still a need for methods to quickly tune actuation parameters for each robot and population or sometimes even for individual users. Protocols where parameters are held constant for multiple minutes have traditionally been used for evaluating responses to parameter changes such as metabolic rate or walking symmetry. However, these discrete protocols are time-consuming. Recently, protocols have been proposed where a parameter is changed in a continuous way. The aim of the present study was to compare effects of continuously varying assistance magnitude with a soft exosuit against discrete step conditions.



	MethodsSeven participants walked on a treadmill wearing a soft exosuit that assists plantarflexion and hip flexion. In Continuous-up, peak exosuit ankle moment linearly increased from approximately 0 to 38\% of biological moment over 10 min. Continuous-down was the opposite. In Discrete, participants underwent five periods of 5 min with steady peak moment levels distributed over the same range as Continuous-up and Continuous-down. We calculated metabolic rate for the entire Continuous-up and Continuous-down conditions and the last 2 min of each Discrete force level. We compared kinematics, kinetics and metabolic rate between conditions by curve fitting versus peak moment.



	ResultsReduction in metabolic rate compared to Powered-off was smaller in Continuous-up than in Continuous-down at most peak moment levels, due to physiological dynamics causing metabolic measurements in Continuous-up and Continuous-down to lag behind the values expected during steady-state testing. When evaluating the average slope of metabolic reduction over the entire peak moment range there was no significant difference between Continuous-down and Discrete. Attempting to correct the lag in metabolics by taking the average of Continuous-up and Continuous-down removed all significant differences versus Discrete. For kinematic and kinetic parameters, there were no differences between all conditions.



	ConclusionsThe finding that there were no differences in biomechanical parameters between all conditions suggests that biomechanical parameters can be recorded with the shortest protocol condition (i.e. single Continuous directions). The shorter time and higher resolution data of continuous sweep protocols hold promise for the future study of human interaction with wearable robots.

},
	isbn = {1743-0003},
	doi = {10.1186/s12984-017-0278-2},
	url = {http://dx.doi.org/10.1186/s12984-017-0278-2},
	author = {Philippe Malcolm and Rossi, Denise Martineli and Christopher Siviy and Lee, Sangjun and Quinlivan, Brendan Thomas and Martin Grimmer and Walsh, Conor J.}
}
@article {1113941,
	title = {Batch Fabrication of Customizable Silicone-Textile Composite Capacitive Strain Sensors for Human Motion Tracking},
	journal = {Advanced Materials Technologies},
	year = {2017},
	abstract = {This paper presents design and batch manufacturing of a highly stretchable textile-silicone capacitive sensor to be used in human articulation detection, soft robotics, and exoskeletons. The proposed sensor is made of conductive knit fabric as electrode and silicone elastomer as dielectric. The batch manufacturing technology enables production of large sensor mat and arbitrary shaping of sensors, which is precisely achieved via laser cutting of the sensor mat. Individual capacitive sensors exhibit high linearity, low hysteresis, and a gauge factor of 1.23. Compliant, low-profile, and robust electrical connections are established by fusing filaments of micro coaxial cable to conductive fabric electrodes of the sensor with thermoplastic film. The capacitive sensors are integrated on a reconstructed glove for monitoring finger motions.},
	url = {http://doi.org/10.1002/admt.201700136},
	author = {Asli Atalay and Vanessa Sanchez and Ozgur Atalay and Daniel M. Vogt and Florian Haufe and Wood, Robert J. and Walsh, Conor J.}
}
@article {1113161,
	title = {Varying negative work assistance at the ankle with a soft exosuit during loaded walking},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {14},
	number = {1},
	year = {2017},
	month = {June 26},
	pages = {62},
	type = {journal article},
	abstract = {
	BackgroundOnly very recently, studies have shown that it is possible to reduce the metabolic rate of unloaded and loaded walking using robotic ankle exoskeletons. Some studies obtained this result by means of high positive work assistance while others combined negative and positive work assistance. There is no consensus about the isolated contribution of negative work assistance. Therefore, the aim of the present study is to examine the effect of varying negative work assistance at the ankle joint while maintaining a fixed level of positive work assistance with a multi-articular soft exosuit.



	MethodsWe tested eight participants during walking at 1.5 ms-1 with a 23-kg backpack. Participants wore a version of the exosuit that assisted plantarflexion via Bowden cables tethered to an off-board actuation platform. In four active conditions we provided different rates of exosuit bilateral ankle negative work assistance ranging from 0.015 to 0.037 W kg-1 and a fixed rate of positive work assistance of 0.19 W kg-1.



	ResultsAll active conditions significantly reduced metabolic rate by 11 to 15\% compared to a reference condition, where the participants wore the exosuit but no assistance was provided. We found no significant effect of negative work assistance. However, there was a trend (p = .08) toward greater reduction in metabolic rate with increasing negative work assistance, which could be explained by observed reductions in biological ankle and hip joint power and moment.



	ConclusionsThe non-significant trend of increasing negative work assistance with increasing reductions in metabolic rate motivates the value in further studies on the relative effects of negative and positive work assistance. There may be benefit in varying negative work over a greater range or in isolation from positive work assistance.

},
	isbn = {1743-0003},
	doi = {10.1186/s12984-017-0267-5},
	url = {http://dx.doi.org/10.1186/s12984-017-0267-5},
	author = {Philippe Malcolm and Lee, Sangjun and Simona Crea and Christopher Siviy and Saucedo, Fabricio and Ignacio Galiana and Panizzolo, Fausto A. and Kenneth G. Holt and Walsh, Conor J.}
}
@article {ADMT:ADMT201700081,
	title = {A Highly Stretchable Capacitive-Based Strain Sensor Based on Metal Deposition and Laser Rastering},
	journal = {Advanced Materials Technologies},
	year = {2017},
	abstract = {Wearable sensing technology is an emerging area and can be utilized for human motion monitoring, physiology monitoring, and human{\textendash}machine interaction. In this paper, a new manufacturing approach is presented to create highly stretchable and soft capacitance-based strain sensors. This involves a rapid surface modification technique based on direct-write laser rastering to create microstructured surfaces on prestrained elastomeric sheets. Then, to impart conductivity, sputtering technology is utilized to deposit aluminum and silver metal layers on the bottom and top surfaces of the elastomer sheet, creating a soft capacitor. During benchtop characterization of the sensors, this study demonstrates that the fabricated electrodes maintain their electrical conductivity up to the 250\% strain, and the sensor shows a linear and repeatable output up to 85\% strain. Finally, their potential is demonstrated for monitoring human motion and respiration through their integration into a wearable arm sleeve and a thoracic belt, respectively.},
	keywords = {capacitive sensors, laser rastering, soft strain sensors, sputtering, surface microtreatment},
	issn = {2365-709X},
	doi = {10.1002/admt.201700081},
	url = {http://doi.org/10.1002/admt.201700081},
	author = {Ozgur Atalay and Asli Atalay and Joshua Gafford and Wang, Hongqiang and Wood, Robert and Conor Walsh}
}
@article {1113086,
	title = {Reducing the metabolic cost of running with a tethered soft exosuit},
	journal = {Science Robotics},
	volume = {2},
	number = {6},
	year = {2017},
	month = {2017-05-31 17:52},
	pages = {eaan6708},
	abstract = {Assisting hip extension with a tethered exosuit and a simulation-optimized force profile reduces metabolic cost of running.},
	url = {http://doi.org/10.1126/scirobotics.aan6708},
	author = {Lee, Giuk and Jinsoo Kim and Panizzolo, Fausto A. and Zhou, Yu Meng and Baker, Lauren M. and Ignacio Galiana and Philippe Malcolm and Walsh, Conor J.}
}
@article {Yandell2017,
	title = {Physical interface dynamics alter how robotic exosuits augment human movement: implications for optimizing wearable assistive devices},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {14},
	number = {1},
	year = {2017},
	pages = {40},
	abstract = {
	\&nbsp;



	BackgroundWearable assistive devices have demonstrated the potential to improve mobility outcomes for individuals with disabilities, and to augment healthy human performance; however, these benefits depend on how effectively power is transmitted from the device to the human user. Quantifying and understanding this power transmission is challenging due to complex human-device interface dynamics that occur as biological tissues and physical interface materials deform and displace under load, absorbing and returning power.



	MethodsHere we introduce a new methodology for quickly estimating interface power dynamics during movement tasks using common motion capture and force measurements, and then apply this method to quantify how a soft robotic ankle exosuit interacts with and transfers power to the human body during walking. We partition exosuit end-effector power (i.e., power output from the device) into power that augments ankle plantarflexion (termed augmentation power) vs. power that goes into deformation and motion of interface materials and underlying soft tissues (termed interface power).



	ResultsWe provide empirical evidence of how human-exosuit interfaces absorb and return energy, reshaping exosuit-to-human power flow and resulting in three key consequences: (i) During exosuit loading (as applied forces increased), about 55\% of exosuit end-effector power was absorbed into the interfaces. (ii) However, during subsequent exosuit unloading (as applied forces decreased) most of the absorbed interface power was returned viscoelastically. Consequently, the majority (about 75\%) of exosuit end-effector work over each stride contributed to augmenting ankle plantarflexion. (iii) Ankle augmentation power (and work) was delayed relative to exosuit end-effector power, due to these interface energy absorption and return dynamics.



	ConclusionsOur findings elucidate the complexities of human-exosuit interface dynamics during transmission of power from assistive devices to the human body, and provide insight into improving the design and control of wearable robots. We conclude that in order to optimize the performance of wearable assistive devices it is important, throughout design and evaluation phases, to account for human-device interface dynamics that affect power transmission and thus human augmentation benefits.



	\&nbsp;

},
	issn = {1743-0003},
	doi = {10.1186/s12984-017-0247-9},
	url = {http://dx.doi.org/10.1186/s12984-017-0247-9},
	author = {Matthew B. Yandell and Quinlivan, Brendan T. and Dmitry Popov and Conor Walsh and Karl E. Zelik}
}
@article {Horvath2017,
	title = {An Intracardiac Soft Robotic Device for Augmentation of Blood Ejection from the Failing Right Ventricle},
	journal = {Annals of Biomedical Engineering},
	year = {2017},
	pages = {1-12},
	abstract = {
	We introduce an implantable intracardiac soft robotic right ventricular ejection device (RVED) for dynamic approximation of the right ventricular (RV) free wall and the interventricular septum (IVS) in synchrony with the cardiac cycle to augment blood ejection in right heart failure (RHF). The RVED is designed for safe and effective intracardiac operation and consists of an anchoring system deployed across the IVS, an RV free wall anchor, and a pneumatic artificial muscle linear actuator that spans the RV chamber between the two anchors. Using a ventricular simulator and a custom controller, we characterized ventricular volume ejection, linear approximation against different loads and the effect of varying device actuation periods on volume ejection. The RVED was then tested in vivo in adult pigs (n\&nbsp;=\&nbsp;5). First, we successfully deployed the device into the beating heart under 3D echocardiography guidance (n\&nbsp;=\&nbsp;4). Next, we performed a feasibility study to evaluate the device{\textquoteright}s ability to augment RV ejection in an experimental model of RHF (n\&nbsp;=\&nbsp;1). RVED actuation augmented RV ejection during RHF; while further chronic animal studies will provide details about the efficacy of this support device. These results demonstrate successful design and implementation of the RVED and its deployment into the beating heart. This soft robotic ejection device has potential to serve as a rapidly deployable system for mechanical circulatory assistance in RHF.

},
	issn = {1573-9686},
	doi = {10.1007/s10439-017-1855-z},
	url = {http://dx.doi.org/10.1007/s10439-017-1855-z},
	author = {Markus A. Horvath and Wamala, Isaac and Rytkin, Eric and Doyle, Elizabeth and Payne, Christopher J. and Thalhofer, Thomas and Berra, Ignacio and Solovyeva, Anna and Saeed, Mossab and Hendren, Sara and Roche, Ellen T. and Pedro J. del Nido and Walsh, Conor J. and Nikolay V. Vasilyev}
}
@article {973646,
	title = {Assistance magnitude versus metabolic cost reductions for a tethered multiarticular soft exosuit},
	journal = {Science Robotics},
	volume = {2},
	number = {2},
	year = {2017},
	month = {18 Jan 2017},
	pages = {eaah4416},
	abstract = {When defining requirements for any wearable robot for walking assistance, it is important to maximize the user{\textquoteright}s metabolic benefit resulting from the exosuit assistance while limiting the metabolic penalty of carrying the system{\textquoteright}s mass. Thus, the aim of this study was to isolate and characterize the relationship between assistance magnitude and the metabolic cost of walking while also examining changes to the wearer{\textquoteright}s underlying gait mechanics. The study was performed with a tethered multiarticular soft exosuit during normal walking, where assistance was directly applied at the ankle joint and indirectly at the hip due to a textile architecture. The exosuit controller was designed such that the delivered torque profile at the ankle joint approximated that of the biological torque during normal walking. Seven participants walked on a treadmill at 1.5 meters per second under one unpowered and four powered conditions, where the peak moment applied at the ankle joint was varied from about 10 to 38\% of biological ankle moment (equivalent to an applied force of 18.7 to 75.0\% of body weight). Results showed that, with increasing exosuit assistance, net metabolic rate continually decreased within the tested range. When maximum assistance was applied, the metabolic rate of walking was reduced by 22.83 {\textpm} 3.17\% relative to the powered-off condition (mean {\textpm} SEM).},
	url = {http://robotics.sciencemag.org/cgi/content/full/2/2/eaah4416?ijkey=6qzJ/i1Y5NG9c\&keytype=ref\&siteid=robotics},
	author = {Quinlivan, Brendan T. and Lee, Sangjun and Philippe Malcolm and Rossi, Denise Martineli and Martin Grimmer and Christopher Siviy and Nikolaos Karavas and Diana Wagner and Alan Asbeck and Ignacio Galiana and Conor J Walsh}
}
@article {973621,
	title = {Automatic design of fiber-reinforced soft actuators for trajectory matching},
	journal = {Proceedings of the National Academy of Sciences (PNAS)},
	volume = {114},
	number = {1},
	year = {2017},
	month = {3 Jan, 2017},
	pages = {51-56},
	abstract = {Soft actuators are the components responsible for producing motion in soft robots. Although soft actuators have allowed for a variety of innovative applications, there is a need for design tools that can help to efficiently and systematically design actuators for particular functions. Mathematical modeling of soft actuators is an area that is still in its infancy but has the potential to provide quantitative insights into the response of the actuators. These insights can be used to guide actuator design, thus accelerating the design process. Here, we study fluid-powered fiber-reinforced actuators, because these have previously been shown to be capable of producing a wide range of motions. We present a design strategy that takes a kinematic trajectory as its input and uses analytical modeling based on nonlinear elasticity and optimization to identify the optimal design parameters for an actuator that will follow this trajectory upon pressurization. We experimentally verify our modeling approach, and finally we demonstrate how the strategy works, by designing actuators that replicate the motion of the index finger and thumb.},
	url = {http://dx.doi.org/10.1073/pnas.1615140114},
	author = {Connolly, Fionnuala and Conor J Walsh and Bertoldi, Katia}
}
@article {973631,
	title = {Interaction Forces of Soft Fiber Reinforced Bending Actuators},
	journal = {IEEE/ASME Transactions on Mechatronics},
	volume = {22},
	number = {2},
	year = {2017},
	month = {12 Dec},
	pages = {717-727},
	abstract = {
	Soft bending actuators are inherently compliant, compact, and lightweight. They are preferable candidates over rigid actuators for robotic applications ranging from physical human interaction to delicate object manipulation. However, characterizing and predicting their behaviors are challenging due to the material nonlinearities and the complex motions they can produce. This paper investigates a soft bending actuator design that uses a single air chamber and fiber reinforcements. Additionally, the actuator design incorporates a sensing layer to enable real-time bending angle measurement for analysis and control. In order to study the bending and force exertion characteristics when interacting with the environment, a quasistatic analytical model is developed based on the bending moments generated from the applied internal pressure and stretches of the soft materials. Comparatively, a finite-element method model is created for the same actuator design. Both the analytical model and the finite-element model are used in the fiber reinforcement analysis and the validation experiments with fabricated actuators. The experimental results demonstrate that the analytical model captures the relationships of supplied air pressure, actuator bending angle, and interaction force at the actuator tip. Moreover, it is shown that an off-the-shelf bend angle sensor integrated to the actuator in this study could provide real-time force estimation, thus eliminating the need for a force sensor.

},
	url = {http://dx.doi.org/10.1109/TMECH.2016.2638468},
	author = {Wang, Zheng and Panagiotis Polygerinos and Overvelde, Johannes TB and Galloway, Kevin C. and Bertoldi, Katia and Conor J Walsh}
}
@article {973641,
	title = {Soft robotic sleeve supports heart function},
	journal = {Science Translational Medicine},
	volume = {9},
	number = {373},
	year = {2017},
	month = {18 Jan 2017},
	abstract = {
	There is much interest in form-fitting, low-modulus, implantable devices or soft robots that can mimic or assist in complex biological functions such as the contraction of heart muscle. We present a soft robotic sleeve that is implanted around the heart and actively compresses and twists to act as a cardiac ventricular assist device. The sleeve does not contact blood, obviating the need for anticoagulation therapy or blood thinners, and reduces complications with current ventricular assist devices, such as clotting and infection. Our approach used a biologically inspired design to orient individual contracting elements or actuators in a layered helical and circumferential fashion, mimicking the orientation of the outer two muscle layers of the mammalian heart. The resulting implantable soft robot mimicked the form and function of the native heart, with a stiffness value of the same order of magnitude as that of the heart tissue. We demonstrated feasibility of this soft sleeve device for supporting heart function in a porcine model of acute heart failure. The soft robotic sleeve can be customized to patient-specific needs and may have the potential to act as a bridge to transplant for patients with heart failure.

},
	url = {http://stm.sciencemag.org/cgi/content/full/9/373/eaaf3925?ijkey=hVQqZatzU8EIM\&keytype=ref\&siteid=scitransmed},
	author = {Roche, Ellen T. and Markus A. Horvath and Wamala, Isaac and Alazmani, Ali and Song, Sang-Eun and Whyte, William and Machaidze, Zurab and Payne, Christopher J. and Weaver, James C and Fishbein, Gregory and Kuebler, Joseph and Nikolay V. Vasilyev and Mooney, David J and Frank A Pigula and Conor J Walsh}
}
@article {973661,
	title = {The Soft Robotics Toolkit: Strategies for Overcoming Obstacles to the Wide Dissemination of Soft-Robotic Hardware},
	journal = {IEEE Robotics and Automation Magazine, Special Issue on Open Source and Widely Disseminated Robot Hardware},
	volume = {24},
	number = {1},
	year = {2017},
	month = {2017},
	pages = {57-64},
	abstract = {
	The Soft Robotics Toolkit (SRT) is an open-access website containing detailed information about the design, fabrication, and characterization of soft-robotic components and systems (Figure 1). Soft robotics is a growing field of research concerned with the development of electromechanical technology composed of compliant materials or structures. The SRT website hosts design files, multimedia fabrication instructions, and software tutorials submitted by an international community of soft-robotics researchers and designers. In this article, we describe the development of the SRT and some challenges in developing widely disseminated robotic-hardware resources. Our attempts to overcome these challenges in the development of the toolkit are discussed by focusing on strategies that have been used to engage participants ranging from K-12 grade students to robotics research groups. A series of design competitions encouraged people to use and contribute to the toolkit. New fabrication methods requiring only low-cost and accessible materials were developed to lower the entry barriers to soft robotics and instructional materials and outreach activities were used to engage new audiences. We hope that our experiences in developing and scaling the toolkit may serve as guidance for other open robotic-hardware projects.

},
	url = {http://dx.doi.org/10.1109/MRA.2016.2639067},
	author = {Holland, D{\'o}nal P. and Abah, Colette and Velasco Enriquez, Marielena and Maxwell Herman and Gareth J. Bennett and Vela, Emir Augusto and Conor J Walsh}
}
@article {973626,
	title = {Toward Medical Devices With Integrated Mechanisms, Sensors, and Actuators Via Printed-Circuit MEMS},
	journal = {ASME Journal of Medical Devices},
	volume = {11},
	number = {1},
	year = {2017},
	month = {11 Jan},
	pages = {011007-011018},
	abstract = {
	Recent advances in medical robotics have initiated a transition from rigid serial manipulators to flexible or continuum robots capable of navigating to confined anatomy within the body. A desire for further procedure minimization is a key accelerator for the development of these flexible systems where the end goal is to provide access to the previously inaccessible anatomical workspaces and enable new minimally invasive surgical (MIS) procedures. While sophisticated navigation and control capabilities have been demonstrated for such systems, existing manufacturing approaches have limited the capabilities of millimeter-scale end-effectors for these flexible systems to date and, to achieve next generation highly functional end-effectors for surgical robots, advanced manufacturing approaches are required. We address this challenge by utilizing a disruptive 2D layer-by-layer precision fabrication process (inspired by printed circuit board manufacturing) that can create functional 3D mechanisms by folding 2D layers of materials which may be structural, flexible, adhesive, or conductive. Such an approach enables actuation, sensing, and circuitry to be directly integrated with the articulating features by selecting the appropriate materials during the layer-by-layer manufacturing process. To demonstrate the efficacy of this technology, we use it to fabricate three modular robotic components at the millimeter-scale: (1) sensors, (2) mechanisms, and (3) actuators. These modules could potentially be implemented into transendoscopic systems, enabling bilateral grasping, retraction and cutting, and could potentially mitigate challenging MIS interventions performed via endoscopy or flexible means. This research lays the ground work for new mechanism, sensor and actuation technologies that can be readily integrated via new millimeter-scale layer-by-layer manufacturing approaches.

},
	url = {http://doi.org/10.1115/1.4035375},
	author = {Joshua B. Gafford and Ranzani, Tommaso and Sheila Russo and Alperen Degirmenci and Samuel B Kesner and Robert D. Howe and Wood, Robert J. and Conor J Walsh}
}
@article {697846,
	title = {Biomechanical and Physiological Evaluation of Multi-joint Assistance with Soft Exosuits},
	journal = {IEEE Transactions on Neural Systems and Rehabilitation Engineering},
	volume = {25},
	number = {2},
	year = {2017},
	month = {28 Jan 2016},
	pages = {119 - 130},
	abstract = {
	To understand the effects of soft exosuits on human loaded walking, we developed a reconfigurable multi-joint actuation platform that can provide synchronized forces to the ankle and hip joints. Two different assistive strategies were evaluated on eight subjects walking on a treadmill at a speed of 1.25 m/s with a 23.8 kg backpack: 1) hip extension assistance and 2) multi-joint assistance (hip extension, ankle plantarflexion and hip flexion). Results show that the exosuit introduces minimum changes to kinematics and reduces biological joint moments. A reduction trend in muscular activity was observed for both conditions. On average, the exosuit reduced the metabolic cost of walking by 0.21 {\textpm} 0.04 W/kg and 0.67 {\textpm} 0.09 W/kg for hip extension assistance and multi-joint assistance respectively, which is equivalent to an average metabolic reduction of 4.6\% and 14.6\% demonstrating that soft exosuits can effectively improve human walking efficiency during load carriage without affecting natural walking gait. Moreover, it indicates that actuating multiple joints with soft exosuits provides a significant benefit to muscular activity and metabolic cost compared to actuating single joint.

},
	url = {http://dx.doi.org/10.1109/TNSRE.2016.2523250},
	author = {Ye Ding and Ignacio Galiana and Alan T. Asbeck and De Rossi, Stefano M.M. and Jaehyun Bae and Teles Dos Santos, Thiago R. and De Araujo, Vanessa L. and Lee, Sangjun and Kenneth G. Holt and Conor J Walsh}
}
@article {975276,
	title = {Effect of timing of hip extension assistance during loaded walking with a soft exosuit},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {2016},
	number = {13},
	year = {2016},
	month = {3 Oct, 2016},
	pages = {87},
	abstract = {\&nbsp;BackgroundRecent advances in wearable robotic devices have demonstrated the ability to reduce the metabolic cost of walking by assisting the ankle joint. To achieve greater gains in the future it will be important to determine optimal actuation parameters and explore the effect of assisting other joints. The aim of the present work is to investigate how the timing of hip extension assistance affects the positive mechanical power delivered by an exosuit and its effect on biological joint power and metabolic cost during loaded walking. In this study, we evaluated 4 different hip assistive profiles with different actuation timings: early-start-early-peak (ESEP), early-start-late-peak (ESLP), late-start-early-peak (LSEP), late-start-late-peak (LSLP).MethodsEight healthy participants walked on a treadmill at a constant speed of 1.5 m {\textperiodcentered} s-1 while carrying a 23 kg backpack load. We tested five different conditions: four with the assistive profiles described above and one unpowered condition where no assistance was provided. We evaluated participants{\textquoteright} lower limb kinetics, kinematics, metabolic cost and muscle activation.ResultsThe variation of timing in the hip extension assistance resulted in a different amount of mechanical power delivered to the wearer across conditions; with the ESLP condition providing a significantly higher amount of positive mechanical power (0.219 {\textpm} 0.006 W {\textperiodcentered} kg-1) with respect to the other powered conditions. Biological joint power was significantly reduced at the hip (ESEP and ESLP) and at the knee (ESEP, ESLP and LSEP) with respect to the unpowered condition. Further, all assistive profiles significantly reduced the metabolic cost of walking compared to the unpowered condition by 5.7 {\textpm} 1.5 \%, 8.5 {\textpm} 0.9 \%, 6.3 {\textpm} 1.4 \% and 7.1 {\textpm} 1.9 \% (mean {\textpm} SE for ESEP, ESLP, LSEP, LSLP, respectively).ConclusionsThe highest positive mechanical power delivered by the soft exosuit was reported in the ESLP condition, which showed also a significant reduction in both biological hip and knee joint power. Further, the ESLP condition had the highest average metabolic reduction among the powered conditions. Future work on autonomous hip exoskeletons may incorporate these considerations when designing effective control strategies.\&nbsp;},
	url = {http://dx.doi.org/10.1186/s12984-016-0196-8},
	author = {Ye Ding and Panizzolo, Fausto A. and Christopher Siviy and Philippe Malcolm and Ignacio Galiana and Kenneth G. Holt and Conor J Walsh}
}
@article {Gafford201678,
	title = {Machine learning approaches to environmental disturbance rejection in multi-axis optoelectronic force sensors},
	journal = {Sensors and Actuators A: Physical},
	volume = {248},
	year = {2016},
	month = {20 July},
	pages = {78 - 87},
	abstract = {Light-Intensity Modulated (LIM) force sensors are seeing increasing interest in the field of surgical robotics and flexible systems in particular. However, such sensing modalities are notoriously susceptible to ambient effects such as temperature and environmental irradiance which can register as false force readings. We explore machine learning techniques to dynamically compensate for environmental biases that plague multi-axis optoelectronic force sensors. In this work, we fabricate a multisensor: three-axis LIM force sensor with integrated temperature and ambient irradiance sensing manufactured via a monolithic, origami-inspired fabrication process called printed-circuit MEMS. We explore machine learning regression techniques to compensate for temperature and ambient light sensitivity using on-board environmental sensor data. We compare batch-based ridge regression, kernelized regression and support vector techniques to baseline ordinary least-squares estimates to show that on-board environmental monitoring can substantially improve sensor force tracking performance and output stability under variable lighting and large (\&gt;100C) thermal gradients. By augmenting the least-squares estimate with nonlinear functions describing both environmental disturbances and cross-axis coupling effects, we can reduce the error in Fx, Fy and Fz by 10\%, 33\%, and 73\%, respectively. We assess viability of each algorithm tested in terms of both prediction accuracy and computational overhead, and analyze kernel-based regression for prediction in the context of online force feedback and haptics applications in surgical robotics. Finally, we suggest future work for fast approximation and prediction using stochastic, sparse kernel techniques.},
	keywords = {Nonlinear regression},
	issn = {0924-4247},
	doi = {http://dx.doi.org/10.1016/j.sna.2016.06.036},
	url = {http://dx.doi.org/10.1016/j.sna.2016.06.036},
	author = {Joshua B. Gafford and Doshi-Velez, Finale and Wood, Robert J. and Conor J Walsh}
}
@article {703236,
	title = {A biologically-inspired multi-joint soft exosuit that can reduce the energy cost of loaded walking},
	journal = {Journal of NeuroEngineering and Rehabilitation},
	volume = {13},
	number = {1},
	year = {2016},
	month = {12 May 2016},
	pages = {1-14},
	abstract = {
	Carrying load alters normal walking, imposes additional stress to the musculoskeletal system, and results in an increase in energy consumption and a consequent earlier onset of fatigue. This phenomenon is largely due to increased work requirements in lower extremity joints, in turn requiring higher muscle activation. The aim of this work was to assess the biomechanical and physiological effects of a multi-joint soft exosuit that applies assistive torques to the biological hip and ankle joints during loaded walking.

},
	url = {http://dx.doi.org/10.1186/s12984-016-0150-9},
	author = {Panizzolo, Fausto A. and Ignacio B. Galiana and Alan T. Asbeck and Christopher Siviy and Kai Schmidt and Kenneth G. Holt and Walsh, Conor J.}
}
@article {Cezar09022016,
	title = {Biologic-free mechanically induced muscle regeneration},
	journal = {Proceedings of the National Academy of Sciences (PNAS)},
	volume = {113},
	number = {6},
	year = {2016},
	month = {9 Feb 2016},
	pages = {1534-1539},
	abstract = {
	Severe skeletal muscle injuries are common and can lead to extensive fibrosis, scarring, and loss of function. Clinically, no therapeutic intervention exists that allows for a full functional restoration. As a result, both drug and cellular therapies are being widely investigated for treatment of muscle injury. Because muscle is known to respond to mechanical loading, we investigated instead whether a material system capable of massage-like compressions could promote regeneration. Magnetic actuation of biphasic ferrogel scaffolds implanted at the site of muscle injury resulted in uniform cyclic compressions that led to reduced fibrous capsule formation around the implant, as well as reduced fibrosis and inflammation in the injured muscle. In contrast, no significant effect of ferrogel actuation on muscle vascularization or perfusion was found. Strikingly, ferrogel-driven mechanical compressions led to enhanced muscle regeneration and a \~{}threefold increase in maximum contractile force of the treated muscle at 2 wk compared with no-treatment controls. Although this study focuses on the repair of severely injured skeletal muscle, magnetically stimulated bioagent-free ferrogels may find broad utility in the field of regenerative medicine.

},
	doi = {10.1073/pnas.1517517113},
	url = {http://dx.doi.org/10.1073/pnas.1517517113 },
	author = {Cezar, Christine A. and Roche, Ellen T. and Vandenburgh, Herman H. and Duda, Georg N. and Walsh, Conor J. and Mooney, David J.}
}
@article {703136,
	title = {Self-Assembling, Low-Cost, and Modular mm-Scale Force Sensor},
	journal = {IEEE Sensors Journal},
	volume = {16},
	number = {1},
	year = {2016},
	month = {1 Jan 2016},
	pages = {69-76. [Cover Article]},
	abstract = {The innovation in surgical robotics has seen a shift toward flexible systems that can access remote locations inside the body. However, a general reliance on the conventional fabrication techniques ultimately limits the complexity and the sophistication of the distal implementations of such systems, and poses a barrier to further innovation and widespread adoption. In this paper, we present a novel, self-assembling force sensor manufactured using a composite lamination fabrication process, wherein linkages pre-machined in the laminate provide the required degrees-of-freedom and fold patterns to facilitate self-assembly. Using the purely 2-D fabrication techniques, the energy contained within a planar elastic biasing element directly integrated into the laminate is released post-fabrication, allowing the sensor to self-assemble into its final 3-D shape. The sensors are batch-fabricated, further driving down the production costs. The transduction mechanism relies on the principle of light intensity modulation, which allows the sensor to detect axial forces with millinewton-level resolution. The geometry of the sensor was selected based on the size constraints inherent in minimally invasive surgery, as well as with a specific focus on optimizing the sensor{\textquoteright}s linearity. The sensor is unique from the fiber-based force sensors in that the emitter and the detector are encapsulated within the sensor itself. The bare sensor operates over a force range of 0-200 mN, with a sensitivity of 5 V/N and a resolution of 0.8 mN. The experimental results show that the sensor{\textquoteright}s stiffness can be tuned using a thicker material for the spring layer and/or encapsulation/integration with soft materials. The empirical validation shows that the sensor has the sensitivity and the resolution necessary to discern the biologically relevant forces in a simulated cannulation task.},
	url = {http://dx.doi.org/10.1109/JSEN.2015.2476368},
	author = {Joshua B. Gafford and Wood, Robert J. and Conor J Walsh}
}
@article {703131,
	title = {Sensory Enhancing Insoles Modify Gait during Inclined Treadmill Walking with Load},
	journal = {Medicine \& Science in Sports \& Exercise},
	volume = {48},
	number = {5},
	year = {2016},
	month = {May 2016},
	pages = {860-868},
	abstract = {Introduction: Inclined walking while carrying a loaded backpack induces fatigue, which may destabilize gait and lead to injury. Stochastic resonance (SR) technology has been used to stabilize spatiotemporal gait characteristics of elderly individuals but has not been tested on healthy recreational athletes. Herein, we determined if sustained vigorous walking on an inclined surface while carrying a load destabilizes gait and if SR has a further effect.
Methods: Participants were fitted with a backpack weighing 30\% of their body weight and asked to walk at a constant self-selected pace while their feet were tracked using an optical motion capture system. Their shoes were fitted with SR insoles that were set at 90\% of the participant{\textquoteright}s sensory threshold. The treadmill incline was increased every 5 min until volitional exhaustion after which the treadmill was returned to a level grade. SR stimulation was turned ON and OFF in a pairwise random fashion throughout the protocol. Spatiotemporal gait characteristics were calculated when SR was ON and OFF for the BASELINE period, the MAX perceived exertion period, and the POST period.
Results: Vigorous activity increases variability in the rhythmic stepping (stride time and stride length) and balance control (double support time and stride width) mechanisms of gait. Overall, SR increased stride width variability by 9\% before, during, and after a fatiguing exercise.
Conclusion: The increased stride time and stride length variability may compromise the stability of gait during and after vigorous walking. However, participants may compensate by increasing double support time and stride width variability to maintain their stability under these adverse conditions. Furthermore, applying SR resulted in an additional increase of stride width variability and may potentially improve balance before, during, and after adverse walking conditions.},
	url = {http://dx.doi.org/10.1249/MSS.0000000000000831},
	author = {Miranda, Daniel L. and Wen-Hao Hsu and Kelsey Petersen and Fitzgibbons, Stacey and Niemi, James and Lesniewski-Laas, Nicholas and Conor J Walsh}
}
@article {548231,
	title = {A Light-Reflecting Balloon Catheter for Atraumatic Tissue Defect Repair},
	journal = {Science Translational Medicine},
	volume = {7},
	number = {306},
	year = {2015},
	month = {2015-09-23 00:00},
	pages = {306ra149},
	abstract = {
	Closing small defects in the body typically requires stitching of tissues during surgery. Toward a minimally invasive approach, Roche et al. engineered a balloon catheter with a reflective surface coating that could be used to adhere biodegradable patches to tissues. The device unfolds the patch and its adhesive, delivers ultraviolet (UV) light, and then applies pressure to stabilize the adhesive as the light cures the polymer. The authors demonstrated catheter-mediated application of the photocurable polymer patch in vivo in rat tissue, with minimal inflammation and complete animal survival, as well as in a challenging septal defect in the beating hearts of pigs. The device was also used to seal porcine stomach ulcers and abdominal hernias ex vivo, suggesting versatility of this approach in repairing defects more easily and atraumatically than sutures.A congenital or iatrogenic tissue defect often requires closure by open surgery or metallic components that can erode tissue. Biodegradable, hydrophobic light-activated adhesives represent an attractive alternative to sutures, but lack a specifically designed minimally invasive delivery tool, which limits their clinical translation. We developed a multifunctional, catheter-based technology with no implantable rigid components that functions by unfolding an adhesive-loaded elastic patch and deploying a double-balloon design to stabilize and apply pressure to the patch against the tissue defect site. The device uses a fiber-optic system and reflective metallic coating to uniformly disperse ultraviolet light for adhesive activation. Using this device, we demonstrate closure on the distal side of a defect in porcine abdominal wall, stomach, and heart tissue ex vivo. The catheter was further evaluated as a potential tool for tissue closure in vivo in rat heart and abdomen and as a perventricular tool for closure of a challenging cardiac septal defect in a large animal (porcine) model. Patches attached to the heart and abdominal wall with the device showed similar inflammatory response as sutures, with 100\% small animal survival, indicating safety. In the large animal model, a ventricular septal defect in a beating heart was reduced to \&lt;1.6 mm. This new therapeutic platform has utility in a range of clinical scenarios that warrant minimally invasive and atraumatic repair of hard-to-reach defects.

},
	doi = {10.1126/scitranslmed.aaa2406},
	url = {http://stm.sciencemag.org/cgi/content/full/7/306/306ra149?ijkey=wFDKnn490V/4g\&keytype=ref\&siteid=scitransmed},
	author = {Ellen T Roche and Fabozzo, Assunta and Lee, Yuhan and Panagiotis Polygerinos and Friehs, Ingeborg and Schuster, Lucia and Whyte, William and Casar Berazaluce, Alejandra Maria and Bueno, Alejandra and Lang, Nora and Pereira, Maria J. N. and Feins, Eric and Wasserman, Steven and O{\textquoteright}Cearbhaill, Eoin D. and Nikolay V. Vasilyev and Mooney, David J and Karp, Jeffrey M and Pedro J. del Nido and Conor J Walsh}
}
@article {390456,
	title = {Mechanical Programming of Soft Actuators by Varying Fiber Angle},
	journal = {Soft Robotics},
	volume = {2},
	number = {1},
	year = {2015},
	month = {March 19 2015},
	pages = {26-32},
	abstract = {In this work we investigate the influence of fiber angle on the deformation of fiber-reinforced soft fluidic actuators and examine the manner in which these actuators extend axially, expand radially and twist about their axis as a function of input pressure. We study the quantitative relationship between fiber angle and actuator deformation by performing finite element simulations for actuators with a range of different fiber angles, and we verify the simulation results by experimentally characterizing the actuators. By combining actuator segments in series, we can achieve combinations of motions tailored to specific tasks. We demonstrate this by using the results of simulations of separate actuators to design a segmented wormlike soft robot capable of propelling itself through a tube and performing an orientation-specific peg insertion task at the end of the tube. Understanding the relationship between fiber angle and pressurization response of these soft fluidic actuators enables rapid exploration of the design space, opening the door to the iteration of exciting soft robot concepts such as flexible and compliant endoscopes, pipe inspection devices, and assembly line robots.},
	url = {http://dx.doi.org/10.1089/soro.2015.0001},
	author = {Connolly, Fionnuala and Panagiotis Polygerinos and Conor J Walsh and Bertoldi, Katia}
}
@article {368676,
	title = {Shape Deposition Manufacturing of a Soft, Atraumatic, Deployable Surgical Grasper},
	journal = {ASME Journal of Mechanisms and Robotics, Special Issue: Fabrication of Fully Integrated Robotic Mechanisms},
	volume = {7},
	number = {2},
	year = {2015},
	month = {May 2015},
	pages = {021006-021006-11},
	abstract = {This paper details the design, analysis, fabrication, and validation of a deployable, atraumatic grasper intended for retraction and manipulation tasks in manual and robotic minimally invasive surgical (MIS) procedures. Fabricated using a combination of shape deposition manufacturing (SDM) and 3D printing, the device (which acts as a deployable end-effector for robotic platforms) has the potential to reduce the risk of intraoperative hemorrhage by providing a soft, compliant interface between delicate tissue structures and the metal laparoscopic forceps and graspers that are currently used to manipulate and retract these structures on an ad hoc basis. This paper introduces a general analytical framework for designing SDM fingers where the desire is to predict the shape and the transmission ratio, and this framework was used to design a multijointed grasper that relies on geometric trapping to manipulate tissue, rather than friction or pinching, to provide a safe, stable, adaptive, and conformable means for manipulation. Passive structural compliance, coupled with active grip force monitoring enabled by embedded pressure sensors, helps to reduce the cognitive load on the surgeon. Initial manipulation tasks in a simulated environment have demonstrated that the device can be deployed though a 15 mm trocar and develop a stable grasp using Intuitive Surgical{\textquoteright}s daVinci robotic platform to deftly manipulate a tissue analog.},
	url = {http://dx.doi.org/10.1115/1.4029493},
	author = {Joshua Gafford and Ye Ding and Andrew Harris and Terrence McKenna and Panagiotis Polygerinos and Donal Holland and Conor J Walsh and Moser, A}
}
@article {261266,
	title = {Soft Exosuit for Hip Assistance},
	journal = {Robotics and Autonomous Systems (RAS) Special Issue on Wearable Robotics},
	volume = {73},
	year = {2015},
	month = {Nov 2015},
	pages = {102-110},
	abstract = {Exoskeletons comprised of rigid load-bearing structures have been developed for many years, but a new paradigm is to create {\textquotedblleft}exosuits{\textquotedblright} that apply tensile forces to the body using textiles and utilize the body{\textquoteright}s skeletal structure to support compressive forces. Exosuits are intended to augment the musculature by providing small to moderate levels of assistance at appropriate times in the walking cycle. They have a number of substantial benefits: with their fabric construction, exosuits eliminate problems of needing to align a rigid frame precisely with the biological joints and their inertia can be extremely low. In this paper, we present a fully portable hip-assistance exosuit that uses a backpack frame to attach to the torso, onto which is mounted a spooled-webbing actuator that connects to the back of the users thigh. The actuators, powered by a geared brushless motor connected to a spool via a timing belt, wind up seat-belt webbing onto the spool so that a large travel is possible with a simple, compact mechanism. Designed to be worn over the clothing, the webbing creates a large moment arm around the hip that provides torques in the sagittal plane of up to 30\% of the nominal biological torques for level-ground walking. Due to its soft design, the system does not restrict the motion of the hip in the ab- and adduction directions or rotation about the leg axis. Here we present the design of the system along with some initial measurements of the system in use during walking on level ground at 1.25 m/s, where it creates a force of up to 150 N on the thigh, equivalent to a torque of 20.5 Nm to assist hip extension.},
	url = {http://dx.doi.org/10.1016/j.robot.2014.09.025},
	author = {Alan T. Asbeck and Kai Schmidt and Conor J Walsh}
}
@article {368666,
	title = {Capacitive Soft Strain Sensors via Multicore-Shell Fiber Printing},
	journal = {Advanced Materials},
	volume = {27},
	number = {15},
	year = {2015},
	month = {17 April 2015},
	pages = {2440-2446. [Back Cover]},
	abstract = {We report a new method for fabricating textile integrable capacitive soft strain sensors based on multicore{\textendash}shell fiber printing. The fiber sensors consist of four concentric, alternating layers of conductor and dielectric, respectively. These wearable sensors provide accurate and hysteresis-free strain measurements under both static and dynamic conditions.},
	url = {http://dx.doi.org/10.1002/adma.201500072},
	author = {Andreas Frutiger and Joseph T. Muth and Daniel M. Vogt and Yi{\u g}it Meng{\"u}{\c c} and Campo, A. and Valentine, A. D. and Conor J Walsh and Lewis, J. A.}
}
@article {261296,
	title = {A Biologically Inspired Soft Exosuit for Walking Assistance},
	journal = {The International Journal of Robotics Research (IJRR)},
	volume = {34},
	number = {6},
	year = {2015},
	month = {May 2015},
	pages = {744-762},
	abstract = {We present the design and evaluation of a multi-articular soft exosuit that is portable, fully autonomous, and provides assistive torques to the wearer at the ankle and hip during walking. Traditional rigid exoskeletons can be challenging to perfectly align with a wearer{\textquoteright}s biological joints and can have large inertias, which can lead to the wearer altering their natural motion patterns. Exosuits, in comparison, use textiles to create tensile forces over the body in parallel with the muscles, enabling them to be light and not restrict the wearer{\textquoteright}s kinematics. We describe the biologically inspired design and function of our exosuit, including a simplified model of the suit{\textquoteright}s architecture and its interaction with the body. A key feature of the exosuit is that it can generate forces passively due to the body{\textquoteright}s motion, similar to the body{\textquoteright}s ligaments and tendons. These passively generated forces can be supplemented by actively contracting Bowden cables using geared electric motors, to create peak forces in the suit of up to 200 N. We define the suit{\textendash}human series stiffness as an important parameter in the design of the exosuit and measure it on several subjects, and we perform human subjects testing to determine the biomechanical and physiological effects of the suit. Results from a five-subject study showed a minimal effect on gait kinematics and an average best-case metabolic reduction of 6.4\%, comparing suit worn unpowered versus powered, during loaded walking with 34.6 kg of carried mass including the exosuit and actuators (2.0 kg on both legs, 10.1 kg total).},
	url = {http://dx.doi.org/10.1177/0278364914562476},
	author = {Alan T. Asbeck and De Rossi, Stefano M.M. and Kenneth G. Holt and Conor J Walsh}
}
@article {Hastings2014,
	title = {Drug and cell delivery for cardiac regeneration},
	journal = {Advanced Drug Delivery Reviews},
	volume = {84},
	year = {2015},
	month = {April 2015},
	pages = {85-106},
	abstract = {
	The spectrum of ischaemic cardiomyopathy, encompassing acute myocardial infarction to congestive heart failure is a significant clinical issue in the modern era. This group of diseases is an enormous source of morbidity and mortality and underlies significant healthcare costs worldwide. Cardiac regenerative therapy, whereby pro-regenerative cells, drugs or growth factors are administered to damaged and ischaemic myocardium has demonstrated significant potential, especially preclinically. While some of these strategies have demonstrated a measure of success in clinical trials, tangible clinical translation has been slow. To date, the majority of clinical studies and a significant number of preclinical studies have utilised relatively simple delivery methods for regenerative therapeutics, such as simple systemic administration or local injection in saline carrier vehicles. Here, we review cardiac regenerative strategies with a particular focus on advanced delivery concepts as a potential means to enhance treatment efficacy and tolerability and ultimately, clinical translation. These include (i) delivery of therapeutic agents in biomaterial carriers, (ii) nanoparticulate encapsulation, (iii) multimodal therapeutic strategies and (iv) localised, minimally invasive delivery via percutaneous transcatheter systems.

},
	keywords = {Regenerative Medicine},
	issn = {0169-409X},
	doi = {http://dx.doi.org/10.1016/j.addr.2014.08.006},
	url = {http://dx.doi.org/10.1016/j.addr.2014.08.006},
	author = {Hastings, Conn L and Ellen T Roche and Eduardo Ruiz-Hernandez and Katja Schenke-Layland and Conor J Walsh and Duffy, Garry P}
}
@article {261301,
	title = {Modeling of Soft Fiber-reinforced Bending Actuators},
	journal = {IEEE Transactions on Robotics},
	volume = {31},
	number = {3},
	year = {2015},
	month = {03 June 2015},
	pages = {778-789},
	abstract = {Soft fluidic actuators consisting of elastomeric matrices with embedded flexible materials are of particular interest to the robotics community because they are affordable and can be easily customized to a given application. However, the significant potential of such actuators is currently limited as their design has typically been based on intuition. In this paper, the principle of operation of these actuators is comprehensively analyzed and described through experimentally validated quasi-static analytical and finite-element method models for bending in free space and force generation when in contact with an object. This study provides a set of systematic design rules to help the robotics community create soft actuators by understanding how these vary their outputs as a function of input pressure for a number of geometrical parameters. Additionally, the proposed analytical model is implemented in a controller demonstrating its ability to convert pressure information to bending angle in real time. Such an understanding of soft multimaterial actuators will allow future design concepts to be rapidly iterated and their performance predicted, thus enabling new and innovative applications that produce more complex motions to be explored.},
	url = {http://dx.doi.org/10.1109/TRO.2015.2428504},
	author = {Panagiotis Polygerinos and Wang, Zheng and Overvelde, Johannes TB and Galloway, Kevin C. and Wood, Robert J. and Bertoldi, Katia and Conor J Walsh}
}
@article {261236,
	title = {Soft Robotic Glove for Combined Assistance and at-Home Rehabilitation},
	journal = {Robotics and Autonomous Systems (RAS) Special Issue on Wearable Robotics},
	volume = {73},
	year = {2015},
	month = {Nov 2015},
	pages = {135-143},
	abstract = {
	This paper presents a portable, assistive, soft robotic glove designed to augment hand rehabilitation for individuals with functional grasp pathologies. The robotic glove utilizes soft actuators consisting of molded elastomeric chambers with fiber reinforcements that induce specific bending, twisting and extending trajectories under fluid pressurization. These soft actuators were mechanically programmed to match and support the range of motion of individual fingers. They demonstrated the ability to generate significant force when pressurized and exhibited low impedance when un-actuated. To operate the soft robotic glove, a control hardware system was designed and included fluidic pressure sensors in line with the hydraulic actuators and a closed-loop controller to regulate the pressure. Demonstrations with the complete system were performed to evaluate the ability of the soft robotic glove to carry out gross and precise functional grasping. Compared to existing devices, the soft robotic glove has the potential to increase user freedom and independence through its portable waist belt pack and open palm design.

},
	url = {http://dx.doi.org/10.1016/j.robot.2014.08.014},
	author = {Panagiotis Polygerinos and Wang, Zheng and Galloway, Kevin C. and Wood, Robert J. and Conor J Walsh}
}
@article {261276,
	title = {Stronger, Smarter, Softer: Next-Generation Wearable Robots},
	journal = {IEEE Robotics \& Automation Magazine},
	volume = {21},
	number = {4},
	year = {2014},
	pages = {22-33},
	abstract = {Exosuits show much promise as a method for augmenting the body with lightweight, portable, and compliant wearable systems. We envision that such systems can be further refined so that they can be sufficiently low profile to fit under a wearer{\textquoteright}s existing clothing. Our focus is on creating an assistive device that provides a fraction of the nominal biological torques and does not provide external load transfer. In early work, we showed that the system can substantially maintain normal biomechanics and positively affect a wearer{\textquoteright}s metabolic rate. Many basic fundamental research and development challenges remain in actuator development, textile innovation, soft sensor development, human-machine interface (control), biomechanics, and physiology, which provides fertile ground for academic research in many disciplines. While we have focused on gait assistance thus far, numerous other applications are possible, including rehabilitation, upper body support, and assistance for other motions. We look forward to a future where wearable robots provide benefits for people across many areas of our society.},
	url = {http://dx.doi.org/10.1109/MRA.2014.2360283},
	author = {Alan T. Asbeck and De Rossi, Stefano and Ignacio Galiana and Ye Ding and Conor J Walsh}
}
@article {368671,
	title = {Mechanical and electrical numerical analysis of soft liquid-embedded deformation sensors analysis},
	journal = {Extreme Mechanics Letters},
	volume = {1},
	year = {2014},
	pages = {42-46},
	abstract = {Soft sensors comprising a flexible matrix with embedded circuit elements can undergo large deformations while maintaining adequate performance. These devices have attracted considerable interest for their ability to be integrated with the human body and have enabled the design of skin-like health monitoring devices, sensing suits, and soft active orthotics. Numerical tools are needed to facilitate the development and optimization of these systems. In this letter, we introduce a 3D finite element-based numerical tool to simultaneously characterize the mechanical and electrical response of fluid-embedded soft sensors of arbitrary shape, subjected to any loading. First, we quantitatively verified the numerical approach by comparing simulation and experimental results of a dog-bone shaped sensor subjected to uniaxial stretch and local compression. Then, we demonstrate the power of the numerical tool by examining a number of different loading conditions. We expect this work will open the door for further design of complex and optimal soft sensors.},
	url = {http://dx.doi.org/10.1016/j.eml.2014.11.003},
	author = {Overvelde, Johannes TB and Yi{\u g}it Meng{\"u}{\c c} and Panagiotis Polygerinos and Wang, Y. and Wang, Z and Conor J Walsh and Wood, Robert J. and Bertoldi, Katia}
}
@article {roche2013biomaterial,
	title = {Comparison of biomaterial delivery vehicles for improving acute retention of stem cells in the infarcted heart},
	journal = {Biomaterials},
	volume = {35},
	number = {25},
	year = {2014},
	pages = {6850-6858},
	publisher = {LIPPINCOTT WILLIAMS \& WILKINS 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA},
	abstract = {Cell delivery to the infarcted heart has emerged as a promising therapy, but is limited by very low acute retention and engraftment of cells. The objective of this study was to compare a panel of biomaterials to evaluate if acute retention can be improved with a biomaterial carrier. Cells were quantified post-implantation in a rat myocardial infarct model in five groups (n = 7{\textendash}8); saline injection (current clinical standard), two injectable hydrogels (alginate, chitosan/β-glycerophosphate (chitosan/{\ss}-GP)) and two epicardial patches (alginate, collagen). Human mesenchymal stem cells (hMSCs) were delivered to the infarct border zone with each biomaterial. At 24 h, retained cells were quantified by fluorescence. All biomaterials produced superior fluorescence to saline control, with approximately 8- and 14-fold increases with alginate and chitosan/β-GP injectables, and 47 and 59-fold increases achieved with collagen and alginate patches, respectively. Immunohistochemical analysis qualitatively confirmed these findings. All four biomaterials retained 50{\textendash}60\% of cells that were present immediately following transplantation, compared to 10\% for the saline control. In conclusion, all four biomaterials were demonstrated to more efficiently deliver and retain cells when compared to a saline control. Biomaterial-based delivery approaches show promise for future development of efficient in vivo delivery techniques.},
	url = {http://dx.doi.org/10.1016/j.biomaterials.2014.04.114},
	author = {Ellen T Roche and Hastings, Conn L and Lewin, Sarah A and Shvartsman, Dmitry E and Brudno, Yevgeny and Nikolay V. Vasilyev and O{\textquoteright}Brien, Fergal J and Conor J Walsh and Duffy, Garry P and Mooney, David J}
}
@article {261196,
	title = {Compact Robotically Steerable Image-Guided Instrument for Multi-Adjacent-Point (MAP) Targeting},
	journal = {IEEE Transactions on Robotics},
	volume = {30},
	number = {4},
	year = {2014},
	pages = {802-815},
	abstract = {Accurately targeting multi-adjacent points (MAPs) during image-guided percutaneous procedures is challenging due to needle deflection and misalignment. The associated errors can result in inadequate treatment of cancer in the case of prostate brachytherapy, or inaccurate diagnosis during biopsy, while repeated insertions increase procedure time, radiation dose, and complications. To address these challenges, we present an image-guided robotic system capable of MAP targeting of irregularly shaped volumes after a single insertion of a percutaneous instrument. The design of the compact CT-compatible drive mechanism is based on a nested screw and screw-spline combination that actuates a straight outer cannula and a curved inner stylet that can be repeatedly straightened when retracted inside the cannula. The stylet translation and cannula rotation/translation enable a 3-D workspace to be reached with the stylet{\textquoteright}s tip. A closed-form inverse kinematics and image-to-robot registration are implemented in an image-guided system including a point-and-click user interface. The complete system is successfully evaluated with a phantom under a Siemens Definition Flash CT scanner. We demonstrate that the system is capable of MAP targeting for a 2-D shape of the letter {\textquotedblleft}H{\textquotedblright} and a 3-D helical pattern with an average targeting error of 2.41 mm. These results highlight the benefit and efficacy of the proposed robotic system in seed placement during image-guided brachytherapy.},
	url = {dx.doi.org/10.1109/TRO.2014.2304773},
	author = {Meysam Torabi and Rajiv Gupta and Conor J Walsh}
}
@article {261136,
	title = {A pediatric robotic thumb exoskeleton for at-home rehabilitation : The isolated orthosis for thumb actuation (IOTA)},
	journal = {International Journal of Intelligent Computing and Cybernetics},
	volume = {7},
	number = {3},
	year = {2014},
	pages = {233-252. [2015 Award for Outstanding Paper]},
	url = {dx.doi.org/10.1108/IJICC-10-2013-0043},
	author = {Patrick Aubin and Kelsey Petersen and Hani Sallum and Conor J Walsh and Annette Correia and Leia Stirling}
}
@article {261211,
	title = {The Soft Robotics Toolkit: Shared Resources for Research and Design},
	journal = {Soft Robotics},
	volume = {1},
	number = {3},
	year = {2014},
	month = {17 Sep 2014},
	pages = {224-230},
	abstract = {This article describes the development of the Soft Robotics Toolkit, a set of open access resources to support the design, fabrication, modeling, characterization, and control of soft robotic devices. The ultimate aim of the toolkit is to support researchers in building upon each other{\textquoteright}s work, and thereby advance the field of soft robotics. An additional aim is to support educators and encourage students to pursue careers in engineering and science by making the resources as accessible as possible. The toolkit was developed and refined through a series of pilot studies and user tests. Specifically, the resources were used by students in a project-based medical device design course; volunteers from a variety of backgrounds tested the toolkit and provided feedback, and soft robotics researchers used the collection of resources and contributed to its development. Throughout all user studies, qualitative data were collected and used to guide improvements to the toolkit. This process of testing and refinement has resulted in a website containing design documentation describing general hardware control platforms and specific soft robotic component designs. The online documentation includes downloadable computer-aided design (CAD) files, detailed multimedia protocols for the fabrication of soft devices, tutorials and scripts for modeling and analyzing soft actuators and sensors, and source code for controlling soft devices. Successive iterations of qualitative data gathering and redesign have confirmed that the toolkit documentation is sufficiently detailed to be useful for researchers from a wide range of backgrounds. To date, the focus of the toolkit has primarily been fluid-actuated robotic systems, but the plan is to expand it to support a wider range of soft robotic-enabling technologies. The toolkit is intended as a community resource, and all researchers working in this field are invited to guide its future development by providing feedback and contributing new content.},
	url = {http://dx.doi.org/10.1089/soro.2014.0010},
	author = {Donal Holland and Evelyn J Park and Panagiotis Polygerinos and Gareth J. Bennett and Conor J Walsh}
}
@article {261221,
	title = {Wearable Soft Sensing Suit for Human Gait Measurement},
	journal = {The International Journal of Robotics Research},
	volume = {33},
	number = {14},
	year = {2014},
	pages = {1748-1764},
	abstract = {Wearable robots based on soft materials will augment mobility and performance of the host without restricting natural kinematics. Such wearable robots will need soft sensors to monitor the movement of the wearer and robot outside the lab. Until now wearable soft sensors have not demonstrated significant mechanical robustness nor been systematically characterized for human motion studies of walking and running. Here, we present the design and systematic characterization of a soft sensing suit for monitoring hip, knee, and ankle sagittal plane joint angles. We used hyper-elastic strain sensors based on microchannels of liquid metal embedded within elastomer, but refined their design with the use of discretized stiffness gradients to improve mechanical durability. We found that these robust sensors could stretch up to 396\% of their original lengths, would restrict the wearer by less than 0.17\% of any given joint{\textquoteright}s torque, had gauge factor sensitivities of greater than 2.2, and exhibited less than 2\% change in electromechanical specifications through 1500 cycles of loading{\textendash}unloading. We also evaluated the accuracy and variability of the soft sensing suit by comparing it with joint angle data obtained through optical motion capture. The sensing suit had root mean square (RMS) errors of less than 5{\textdegree} for a walking speed of 0.89 m/s and reached a maximum RMS error of 15{\textdegree} for a running speed of 2.7 m/s. Despite the deviation of absolute measure, the relative repeatability of the sensing suit{\textquoteright}s joint angle measurements were statistically equivalent to that of optical motion capture at all speeds. We anticipate that wearable soft sensing will also have applications beyond wearable robotics, such as in medical diagnostics and in human{\textendash}computer interaction.},
	url = {http://dx.doi.org/10.1177/0278364914543793},
	author = {Yi{\u g}it Meng{\"u}{\c c} and Yong-Lae Park and Hao Pei and Daniel M. Vogt and Patrick M. Aubin and Ethan Winchell and Lowell Fluke and Leia Stirling and Wood, Robert J. and Conor J Walsh}
}
@article {260841,
	title = {A Bioinspired Soft Actuated Material},
	journal = {Advanced Materials},
	volume = {26},
	number = {8},
	year = {2014},
	pages = {1200-1206},
	abstract = {A class of soft actuated materials that can achieve lifelike motion is presented. By embedding pneumatic actuators in a soft material inspired by a biological muscle fibril architecture, and developing a simple finite element simulation of the same, tunable biomimetic motion can be achieved with fully soft structures, exemplified here by an active left ventricle simulator.},
	url = {http://dx.doi.org/10.1002/adma.201304018},
	author = {Ellen T Roche and Wohlfarth, Robert and Overvelde, Johannes TB and Nikolay V. Vasilyev and Frank A Pigula and Mooney, David J and Bertoldi, Katia and Conor J Walsh}
}
@article {109211,
	title = {Cable-driven Finger Exercise Device with Extension Return Springs for Recreating Standard Therapy Exercises},
	journal = {ASME Journal of Medical Devices},
	volume = {8},
	year = {2014},
	pages = {014502},
	abstract = {Finger therapy exercises, which include table-top, proximal-interphalangeal blocking, straight-fist, distal-interphalangeal blocking, hook-fist and fist exercises, are important for maintaining hand mobility and preventing development of tendon adhesions in post-operative hand-injury patients. Continuous passive motion devices act as an adjunct to the therapist in performing therapy exercises on patients, however current devices are unable to recreate these exercises well. The current study aimed to design and evaluate a finger exercise device that reproduces the therapy exercises, by adopting a cable-actuated flexion and spring-return extension mechanism. The device comprises of phalanx interface attachments, connected by palmar-side cables to spooling actuators and linked by dorsal-side extension springs to provide passive return. Two designs were tested, whereby the springs had similar (Design 1) or different stiffnesses (Design 2). The device was donned onto a model hand and actuated into the desired therapy postures. Our findings indicated that Design 1 is able to recreate table-top, straight-fist and fist exercises, while Design 2 is capable of further replicating distal-interphalangeal blocking, proximal-interphalangeal blocking and hook-fist exercises. Considering that these therapy exercises have not yet been well-replicated in current devices, developing a new device that reproduces the exercises will be beneficial for post-operative rehabilitation of patients.},
	author = {Chen-Hua Yeow and Andrew T. Baisch and Simon G. Talbot and Conor J Walsh}
}
@article {260846,
	title = {Pneumatic Networks for Soft Robotics that Actuate Rapidly},
	journal = {Advanced Functional Materials},
	volume = {24},
	number = {15},
	year = {2014},
	pages = {2163-2170},
	abstract = {Soft robots actuated by inflation of a pneumatic network (a {\textquotedblleft}pneu-net{\textquotedblright}) of small channels in elastomeric materials are appealing for producing sophisticated motions with simple controls. Although current designs of pneu-nets achieve motion with large amplitudes, they do so relatively slowly (over seconds). This paper describes a new design for pneu-nets that reduces the amount of gas needed for inflation of the pneu-net, and thus increases its speed of actuation. A simple actuator can bend from a linear to a quasi-circular shape in 50 ms when pressurized at ΔP = 345 kPa. At high rates of pressurization, the path along which the actuator bends depends on this rate. When inflated fully, the chambers of this new design experience only one-tenth the change in volume of that required for the previous design. This small change in volume requires comparably low levels of strain in the material at maximum amplitudes of actuation, and commensurately low rates of fatigue and failure. This actuator can operate over a million cycles without significant degradation of performance. This design for soft robotic actuators combines high rates of actuation with high reliability of the actuator, and opens new areas of application for them.},
	url = {http://dx.doi.org/10.1002/adfm.201303288},
	author = {Mosadegh, Bobak and Panagiotis Polygerinos and Keplinger, Christoph and Wennstedt, Sophia and Shepherd, Robert F. and Gupta, Unmukt and Shim, Jongmin and Bertoldi, Katia and Conor J Walsh and Whitesides, George M.}
}
@article {260221,
	title = {A New Laparoscopic Morcellator Using an Actuated Wire Mesh and Bag},
	journal = {ASME Journal of Medical Devices},
	volume = {8},
	number = {1},
	year = {2014},
	pages = {011009},
	url = {http://dx.doi.org/10.1115/1.4026294},
	author = {Alexander Isakov and Kimberly M. Murdaugh and William C. Burke and Sloan Zimmerman and Ellen Roche and Donal Holland and Einarsson, Jon I and Conor J Walsh}
}
@article {550541,
	title = {Smaller, Softer, Safer, Smarter Robots},
	journal = {Science Translational Medicine},
	volume = {5},
	number = {210},
	year = {2013},
	month = {6 Nov 2013},
	pages = {210ed19},
	url = {http://stm.sciencemag.org/content/5/210/210ed19},
	author = {Wood, Robert J. and Conor J Walsh}
}
@article {109206,
	title = {Classroom to Clinic: Merging Education and Research to Efficiently Prototype Medical Devices},
	journal = {IEEE Journal of Translational Engineering in Health and Medicine},
	volume = {1},
	year = {2013},
	pages = {4700107},
	abstract = {Innovation in patient care requires both clinical and technical skills, and this paper presents the methods and outcomes of a nine-year, clinical-academic collaboration to develop and evaluate new medical device technologies, while teaching mechanical engineering. Together, over the course of a single semester, seniors, graduate students, and clinicians conceive, design, build, and test proof-of-concept prototypes. Projects initiated in the course have generated intellectual property and peer-reviewed publications, stimulated further research, furthered student and clinician careers, and resulted in technology licenses and start-up ventures.},
	url = {http://dx.doi.org/10.1109/JTEHM.2013.2271897},
	author = {Nevan C. Hanumara and Nikolai D. Begg and Conor J Walsh and David Custer and Rajiv Gupta and Lynn R. Osborn and Alexander H. Slocum}
}
@article {109191,
	title = {Hemodialysis graft resistance adjustment device},
	journal = {ASME Journal of Medical Devices},
	volume = {6},
	year = {2012},
	pages = {021011-021016},
	abstract = {Up to eight percent of patients develop steal syndrome after prosthetic dialysis access graft placement, which is characterized by low blood flow to the hand. Steal syndrome results in a cold hand, pain, and in extreme cases, loss of function and tissue damage. A practical and easy way of adjusting the fluidic resistance in a graft to attenuate the risk of steal physiology would greatly benefit both surgeons and patients. This paper describes the design and development of a device that can be attached to a dialysis access graft at the time of surgical implantation to enable providers to externally adjust the resistance of the graft postoperatively. Bench level flow experiments and magnetic setups were used to establish design requirements and test prototypes. The Graft Resistance Adjustment Mechanism (GRAM) can be applied to a standard graft before or after it is implanted and a non-contact magnetic coupling enables actuation through the skin for graft compression. The device features a winch-driven system to provide translational movement for a graft compression unit. We expect such a device to enable noninvasive management of steal syndrome in a manner that does not change the existing graft and support technologies, thus reducing patient complications and reducing costs to hospitals.},
	author = {Brandon J. Hopkins and Huayin Wu and William H. Marks and Qimin Quan and Samuel B Kesner and Keith Ozaki and Conor J Walsh}
}
@article {260081,
	title = {Bio-Inspired Design of Soft Robotic Assistive Devices: The Interface of Physics, Biology, and Behavior},
	journal = {Ecological Psychology},
	volume = {24},
	number = {4},
	year = {2012},
	pages = {300-327},
	abstract = {Wearable assistive robotic devices are characterized by an interface, a meeting place of living tissue and mechanical forces, at which potential and kinetic energy are converted to one or the other form. Ecological scientists may make important contributions to the design of device interfaces because of a functional perspective on energy and information exchange. For ecological scientists, (a) behavioral forms are an assembly of whole functional systems from available parts, emerging in energy flows, and (b) nature explores for informationally based adaptive solutions to assemble behavioral forms by generating spontaneous patterns containing fluctuations. We present data from ongoing studies with infants that demonstrate how infants may explore for adaptive kicking solutions. Inspired by the ecological perspective and data from developing humans, ecological scientists may design interfaces to assist individuals with medical conditions that result in physical and/or mental impairment. We present one such device, what is called the {\textquotedblleft}second skin,{\textquotedblright} to illustrate how a soft, prestressed material, worn on the skin surface, may be used synergistically with synthetic and biological muscles for assisting action. Our work on the second skin, thus far, suggests a set of ecologically inspired principles for design of wearable assistive robotic devices.},
	url = {http://dx.doi.org/10.1080/10407413.2012.726179},
	author = {Eugene Goldfield and Yong-Lae Park and Bor-Rong Chen and Wen-Hao Hsu and Diana Young and Michael Wehner and Damian G. Kelty-Stephen and Leia Stirling and Marc Weinberg and Newman, D. and Radhika Nagpal and Elliot Saltzman and Kenneth G. Holt and Conor J Walsh and Wood, Robert J.}
}
@article {260046,
	title = {CT-Compatible Medical Drilling Stylet for Percutaneous Interventions},
	journal = {ASME Journal of Medical Devices},
	volume = {6},
	number = {4},
	year = {2012},
	pages = {041001},
	url = {dx.doi.org/10.1115/1.4007280},
	author = {Conor J Walsh and Meskers and Alexander H. Slocum and Rajiv Gupta}
}
@article {259726,
	title = {Smaller and Deeper Lesions Increase the Number of Acquired Scan Series in CT-guided Lung Biopsy},
	journal = {Journal of Thoracic Imaging},
	volume = {26},
	number = {3},
	year = {2011},
	pages = {196-203},
	author = {Conor J Walsh and Bishnu H. Sapkota and Mannudeep K. Kalra and Nevan C. Hanumara and Bob Liu and Jo-Anne Shepard and Rajiv Gupta}
}
@article {259666,
	title = {Transmission Ratio Based Analysis and Robust Design of Mechanisms},
	journal = {Precision Engineering},
	volume = {34},
	number = {4},
	year = {2010},
	pages = {790-797},
	abstract = {This paper proposes an analytical approach to the robust design of mechanisms, to achieve motion and accuracy requirements given a desired transmission ratio and allowable geometrical variations. The focus is on four-bar and slider-crank mechanisms, which are common elements for the transmission of rotary motion, especially over distances, which are too big for the use of conventional elements such as gears, and motion along a predefined guide-curve, which often is a straight line. For many power transmission applications, a constant relation between the motions of an input and corresponding output element is required. For a four-bar linkage, a value of 1 is the only possible constant transmission ratio{\textemdash}achieved when the mechanism has a parallelogram configuration. In the case of a slider-crank linkage a constant transmission ratio can be achieved with a properly designed circular guide-curve, which makes the slider-crank essentially equivalent to a four-bar. In practice, however, as a result of variations in link lengths due to manufacturing tolerances and load-induced or thermal deformations, the transmission ratio for a parallelogram four-bar linkage will deviate substantially from its ideal theoretical value of 1. Even small changes in link lengths due to deformations or joint backlash can cause unacceptable instantaneous transmission ratio variations. The concepts presented are not limited to the design of four-bars and slider-cranks but can also be applied universally in the design of other mechanisms.},
	url = {dx.doi.org/10.1016/j.precisioneng.2010.03.010},
	author = {Gerald Rothenhofer and Conor J Walsh and Alexander H. Slocum}
}
@article {259676,
	title = {Women with Anorexia Nervosa: Finite Element and Trabecular Structure Analysis by Using Flat-Panel Volume CT},
	journal = {Radiology},
	volume = {257},
	number = {1},
	year = {2010},
	pages = {167-174},
	author = {Conor J Walsh and Catherine M. Phan and Madhusmita Misra and Miriam A. Bredella and Karen K. Miller and Pouneh K. Fazeli and Harun H. Bayraktar and Anne Klibanski and Rajiv Gupta}
}
@article {259621,
	title = {Imaging of the Calf Vocal Fold with High Frequency Ultrasound},
	journal = {The Laryngoscope},
	volume = {118},
	number = {Oct.},
	year = {2008},
	pages = {1894-1899},
	author = {Conor J Walsh and James T. Heaton and James B. Kobler and Thomas L. Szabo and Steven M. Zeitels}
}
@article {259611,
	title = {Engineering, Science and Medicine: Transforming Healthcare},
	journal = {Royal College of Surgeons in Ireland Student Medical Journal},
	volume = {1},
	number = {1},
	year = {2008},
	pages = {56-59},
	author = {Conor J Walsh and Cathal K. Kearney}
}
@article {259616,
	title = {A Patient-Mounted, Telerobotic Tool for CT-Guided Percutaneous Interventions},
	journal = {ASME Journal of Medical Devices},
	volume = {2},
	number = {1},
	year = {2008},
	author = {Conor J Walsh and Nevan C. Hanumara and Alexander H. Slocum and Jo-Anne Shepard and Rajiv Gupta}
}
@article {259606,
	title = {Quasi-Passive Leg Exoskeleton for Load Carrying Augmentation},
	journal = {International Journal of Humanoid Robotics, Special Issue: Active Exoskeletons},
	volume = {4},
	number = {3},
	year = {2007},
	pages = {487-506},
	abstract = {A quasi-passive leg exoskeleton is presented for load-carrying augmentation during walking. The exoskeleton has no actuators, only ankle and hip springs and a knee variable damper. Without a payload, the exoskeleton weighs 11.7kg and requires only 2 Watts of electrical power during loaded walking. For a 36kg payload, we demonstrate that the quasi-passive exoskeleton transfers on average 80\% of the load to the ground during the single support phase of walking. By measuring the rate of oxygen consumption on a study participant walking at a self-selected speed, we find that the exoskeleton slightly increases the walking metabolic cost of transport (COT) as compared to a standard loaded backpack (10\% increase). However, a similar exoskeleton without joint springs or damping control (zero-impedance exoskeleton) is found to increase COT by 23\% compared to the loaded backpack, highlighting the benefits of passive and quasi-passive joint mechanisms in the design of efficient, low-mass leg exoskeletons.},
	author = {Conor J Walsh and Ken Endo and Hugh Herr}
}
