Optimization of the Performances of a Two-Joint Robotic Arm using Sliding Mode Control

Abstract

In this paper, we worked on the control of the angular position of a two-joint robotic arm by the sliding mode technique, after having establishing the dynamic equations of the system by the Lagrange method, with the purpose of improving the performances of the system by acting on certain parameters related to the sliding mode technique. The simulation results show an optimization of the sliding mode controller parameters, generally, in the response of the controlled system, which consists on minimizing error and settling time, and eliminating the unwanted phenomenon of chattering, after finding the optimal values of these parameters. Verification by simulation of the robustness of the optimized robotic arm shows that its response is independent of the dimensions and masses of the bodies of this robotic arm, as well as of the applied load. this answer always corresponds to the best performances of speed, settling time and margin of error. the only quantity that varies according to the parameters of the robotic arm and the applied load is the torque required. This couple has a compensating effect to the change of these internal parameters and of this applied load, to keep the same optimal response on the condition of communicating these changes with the controller.