User-modulated impedance control using two-site proportional myoelectric signals

Commercially available electrically powered prosthetic elbows are stiff and unyielding. Making these artificial limb replacements more closely mimic human elbows by increasing their compliance may be beneficial. In addition to having increased compliance compared with current electrically powered prosthetic elbows, humans modulate the overall impedance of their joints. The author proposes to create a user-modulated impedance controlled prosthesis and to see if persons using this prosthesis demonstrate improved movement performance using it compared with traditional motion control. Specifically, the author proposes to: (1) Quantify flexion/extension compliance modulation at the interface between the residual limb's humerus of a person with an above-elbow amputation and their socket. (2) Create a compliant clinically applicable prosthetic elbow that controls motion and impedance. (3) Compare user performance when using impedance control and traditional control of a prosthetic elbow in the presence of environmental perturbations and mental distraction. (4) Determine if users modulate impedance of the prosthetic elbow when they interact with different environments.; These studies should lead to improvements in future prostheses and test the value of impedance control in prosthetic and robotic applications.