Dimensional Synthesis and Optimization of a Six-Bar Linkage Mechanism for Gait Rehabilitation

Abstract

Linkage mechanisms, among which most are four-bar linkage mechanisms or six-bar linkage mechanisms, are major parts of robotic gait rehabilitation systems. The dimensional synthesis and optimization of a six-bar linkage mechanism for human gait rehabilitation is described in this paper. The relationship between the limiting position characteristics of linkages and gait trajectory phases need to be analyzed due to the timing requirements of gait training. The process includes (1) path transformation from ankle trajectory to the desired objective path curve, (2) the new dimensional synthesis of the proposed mechanism, (3) optimization and simulation of the proposed mechanism. The coupler curve generated by the mechanism designed with this process and the desired objective pattern are shown to match well with each other, illustrating the feasibility of the presented method.