Publications

2007
C. J. Walsh, K. Endo, and H. Herr, “Quasi-Passive Leg Exoskeleton for Load Carrying Augmentation,” International Journal of Humanoid Robotics, Special Issue: Active Exoskeletons, vol. 4, no. 3, pp. 487-506, 2007.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.

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C. J. Walsh, N. C. Hanumara, R. Gupta, J. - A. Shepard, and A. H. Slocum, “Evaluation of a Patient-Mounted, Remote Needle Guidance and Insertion System for CT-Guided, Percutaneous Lung Biopsies,” in Proceedings of the 2nd Frontiers in Biomedical Devices Conference, Irvine, California, 2007. PDF
N. C. Hanumara, C. J. Walsh, R. Gupta, J. - A. Shepard, and A. H. Slocum, “Human Factors Design for Intuitive Operation of a Low-cost, Image-Guided, Tele-Robotic Biopsy Assistant,” in Proceedings of the IEEE Engineering in Medicine and Biology Conference, Lyon, France, 2007, pp. 1257-1260. PDF
M. P. Ottensmeyer, M. Yip, C. J. Walsh, J. B. Kobler, J. T. Heaton, and S. M. Zeitels, “Intra-operative Laryngoscopic Instrument for Characterizing Vocal Fold Visco-elasticity,” in Proceedings of the 2nd Frontiers in Biomedical Devices Conference, Irvine, California, 2007. PDF
2006
C. J. Walsh, K. Pasch, and H. Herr, “An Autonomous, Underactuated Exoskeleton for Load Carrying Augmentation,” in Proc. Inter. Conf. on IROS, Beijing, China, 2006, pp. 1410-1415. PDF
C. J. Walsh, D. Paluska, K. Pasch, W. Grand, A. Valiente, and H. Herr, “Development of a Lightweight, Under-actuated Exoskeleton to Assist in Load Carrying in Walking,” in Proceedings of the IEEE International Conference on Robotics and Automation, Orlando, Florida, 2006, pp. 3485-3491. PDF
2005
S. R. H. Barrett, R. Gupta, N. C. Hanumara, A. H. Slocum, and C. J. Walsh, “Remote Needle Guidance System for Percutaneous Image Guided Biopsies,” in Proc. American Society of Mechanical Engineers International Design Engineering and Technical Conferences, Long Beach, California, 2005. PDF

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