Research on Tracking Control of Circular Trajectory of Robot Based on the Variable Integral Sliding Mode PD Control Algorithm

Abstract

An algorithm named Variable Integral Sliding Mode PD Control (VISMPDC) which combines integral sliding mode control with the PD control method is proposed to improve the trajectory tracking control accuracy and robustness of a robot along the representative circular trajectory. According to the difference of the time weighting coefficients in the time-jerk optimal objective function (when the time weighting coefficient increases from 0 to 1, the movement velocity of a robot changes from low to high), the obtained optimization trajectories are divided into two categories: low-speed and high-speed; and then the integral sliding mode control parameters are adjusted, while the parameters of the PD control method keep unchanged. The experimental results on a 7-DOF robot show that the proposed algorithm is effective and feasible when compared with the traditional PD control method. In conclusion, the algorithm presents a solution for the typical circular trajectory tracking control problem of a robot.