Pilot study of the microprocessor-controlled prosthetic knee with a novel hydraulic damper.

Abstract

A prosthetic knee is the key component of the transfemoral prosthesis. The performance of the prosthetic knee determines the walking ability of transfemoral amputees. This study proposes a microprocessor-controlled prosthetic knee with a novel hydraulic damper and evaluates the performance of the prosthetic knee by gait symmetry index. The homotaxial knee joint with electrical-controlled hydraulic cylinder which adjusts knee flexion and extension damping independently and continuously by single motor was designed. Gait symmetry tests under different walking speeds (0.6m/s, 1.1m/s and 1.6m/s) were conducted to evaluate the performance of the proposed microprocessor-controlled prosthetic knee. The symmetry index values indicated that the stance phase was more asymmetry than swing phase. In the swing phase, the knee angle symmetry was observed in different speeds. The number values of symmetry index were smaller than 15% in swing phase. The proposed microprocessor-controlled prosthetic knee could meet the demands of walking.