Smart Prosthetic Knee for Above-Knee Amputees

In this paper, we proposed a smart prosthetic knee that is driven by a novel cam-leaf spring-MR damper mechanism (a) (CLS-MRD) and a DC motor. The DC motor can work as a generator to harvest energy and as an actuator to actively regulate the knee angle or provide positive work. The CLS-MRD can work in three modes by controlling the MR damper. When the MR damper is powered on to be knocked, the leaf spring is deformed by the cam to store energy and provide a bias torque to bear body weight (in the early stance phase). When the MR damper is powered on, but there is a relative motion between the damper piston and the damper housing, the CLS-MRD provides an adjustable damping force (in the late stance phase). When the MR damper is powered off, the CLS-MRD is released (in the swing phase). We have conducted preliminary testing on an above-knee amputee to validate the design.