Fuzzy Identification and Delay Compensation based on the Force/Position Control Scheme of the 5-DOF Redundantly Actuated Parallel Robot

Abstract

This paper presents a fuzzy identification method for the dynamic model of the 6PUS-UPU redundantly actuated parallel robot. The T–S fuzzy model is the model of the whole system, the input is the pose of the moving platform and the output is the driving force. The fuzzy model is regarded as the feedback loop between the moving platform and the force branch. The dynamic model is built by Kane’s method, and a novel closed-loop force/position hybrid control structure with the pose error for a complex multi-DOF spatial redundantly actuated parallel robot is developed. A proportional-integral force controller is presented based on the structure to obtain an optimal solution under the model identification. The proposed procedure is verified by Matlab/Adams simulation with a 6PUS-UPU simulation platform. The simulation results show that the proposed method is valid for designing the 5-DOF redundantly actuated parallel robot with the movable platform pose error. This paper designs the Smith predictor to solve the delay problem of the redundant force control branch.