Abstract
This paper deals with the development of the new model of Above-Knee (A/K) prosthesis WLP-5 system, which can be adaptable to voluntary walking period. First, simulational analysis of the swing phase locomotion of A/K prosthesis on level walking was performed, the results of which revealed that the A/K prosthesis must have following performances to be used in amputee's voluntary walking period. One is the performance that can change the damping coefficient of knee joint rotation. The other is the ability to generate a little driving torque during a swing phase. From these results, the new model of A/K prosthesis WLP-5 system having these two functions was developed.
The WLP-5 system has the following mechanisms:
1) The mechanism to change the damping coefficient of the knee joint rotation by adjusting a needle valve regulated by a DC motor.
2) The mechanism to generate a little driving torque by self-accumulated air which is compressed by rotation of an ankle joint during a stance phase.
From the results of the walking experiments with amputees, it was confirmed that the WLP-5 system generated adequate knee-torque with a wide range of walking period (1.6-2.2sec) during the level walking.
