Dimensional optimisation of a 3-DoF spherical parallel manipulator for rehabilitation by using firefly algorithm

Abstract

This study deals with the dimensional optimisation problem of a 3-DoF 3-legged spherical parallel robot with a desired workspace, which was planned to be used as a rehabilitation robot for human wrist. The movement of the end-effector will provide all degrees of freedom (DoFs) of human wrist joint. Each leg of manipulator has two spherical links and all joint axes on these links are intersecting on a common point. Inverse kinematics equations are solved and Jacobian matrices are obtained for this mechanism to obtain an objective function for optimisation algorithm. Later, the architectural optimisation with desired workspace are made by using Firefly Algorithms. Finally, a simulation was done to test the obtained dimensional parameters in desired workspace.