Design, development, and bench-top testing of a powered polycentric ankle prosthesis

摘要

Powered ankle-foot prostheses must provide high power and torque while satisfying stringent size and weight requirements. Previous works have focused on improving the prosthesis torque/weight ratio with novel actuation systems such as series and parallel elastic actuators, clutchable leverages, and pneumatic artificial muscles. In this paper, we propose an alternative design approach to minimize the prosthesis size and weight, while improving torque generation and electrical efficiency, based on a polycentric kinematic chain. The proposed approach is implemented on a novel powered polycentric ankle prosthesis (p2Ankle). Kinematics and mechatronic design are presented together with bench-top testing. Preliminary validation in standing and walking is conducted with an able-bodied user using a bypass orthosis.