An Additive Millimeter-Scale Fabrication Method for Soft Biocompatible Actuators and Sensors


S. Russo, T. Ranzani, C. J. Walsh, and R. J. Wood, “An Additive Millimeter-Scale Fabrication Method for Soft Biocompatible Actuators and Sensors,” Advanced Materials Technologies, 2017.
PDF3.14 MB
Supporting Information7.18 MB


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.

Publisher's Version

Last updated on 08/10/2017