Synthetic Muscle Electroactive Polymer (EAP) based actuation and pressure sensing for prosthetic and robotic gripper applications

摘要

Ras Labs’ Synthetic Muscle technology promises to resolve major issues facing amputees, most notably the pain of prosthetic slippage and tissue breakdown. Synthetic Muscle, comprising electroactive polymers (EAPs), actively expand or contract at low voltages, while offering impact resistance and pressure sensing, in one integrated solution. In collaboration with United Prosthetics (UPI), customer testing was initiated with these EAP based pads located in strategic areas of the prosthetic socket of both below knee (BK) and above knee (AK) amputees for evaluation and feedback, with very promising results. The goal is to give amputees natural locomotion with a worry-free prosthesis, maintaining dynamic perfect fit throughout the day and preventing tissue damage from even beginning to occur. Robotic gripper applications, with sensing fingertips, were also prototyped. Characterization of Synthetic Muscle as dual use pressure sensors was investigated, with variable voltage observed and quantified when the EAP sensor was mechanically compressed. The integration of EAP shape-morphing actuation into grippers was also initiated. The EAP shape-morphing control is expected to be modulated as needed by controlling the voltage level. This technology is expected to provide for an adjustable prosthetic liner or socket that can maintain dynamic perfect fit and for biomimetic prosthetic hands and robotic grippers.