抄録
Previous study developed an above-knee prosthesis with fix/extension mechanism of knee joint by using the floor reaction. The prosthesis has a lever on the bottom of foot, and caliper brake on the knee joint of prosthesis is active when the wire is pulled by push-in of the foot lever. The movement of the knee joint is fixed by champing force caliper on the brake, by push-in of the foot lever. Furthermore, compressing the input cylinder by the movement of the ankle joint, the output cylinder extends through the fluid pressured generate a support torque extension moment of the knee. In the study, investigates experimentally assistive effect and improves the femoral prosthesis which enables to reduce muscle burden of a stand leg on the stairs when walking on steps with 20 cm height. The Fix/extension mechanism realized by the lever mechanism has problem during stance phase. When the floor-reaction acting position at the toe during stance phase, the force for fixing the knee joint is not obtained by input lever. Therefore, by changing the design of the input part of the design which uses the arch straucture on the foot, regardless of the position of the floor reaction point. By experiments using EMG, this study shows that it is possible to reduce the muscle activity of the vastus medicals of the sound leg, and the muscle activity agree with muscle load of a healthy person.
