Energy regeneration-based hybrid control for transfemoral prosthetic legs using four-bar mechanism

This paper presents an energy regeneration-based hybrid control method for transfemoral prosthetic legs using a four-bar linkage mechanism. To do that, we consider a model of transfemoral prosthetic leg with three-degrees of freedom that employs a knee mechanism using a four-bar linkage mechanism. We also focus on suggesting a practical strategy for effective implementation rather than a complex algorithm. In this point of view, we devise a hybrid controller for the prosthetic leg. Actually, the motions of the hip mechanism of the leg are controlled by a PID control method and the knee joint is controlled by an impedance control method. We also consider an electrical energy regeneration module for effective energy utilization. Through an exemplary walk simulation, we show the availability of the hybrid controller for such a transfemoral prosthetic leg and also address the advantages of using such a four-bar mechanism and an energy regeneration module for effective driving the knee joint. It is finally concluded that the proposed hybrid controller can be applied for effective control of transfemoral prosthetic legs using such a four-bar mechanism.