Robust controller design for robot joint position servo systems

Abstract

For the position servo control problem of a robot joint control system affected by the uncertainty of external disturbances, a model-based robust controller is designed in this paper. The designed controller is capable of suppressing the effect of external uncertain disturbances on the robot joint control system while improving the position servo accuracy and anti-interference capability of the system. The control scheme consists of two parts, the nominal part represents the model of the system dynamics, which is used to suppress any tendency to deviate from the constraints; the second part is the robust term, which is used to deal with the effects of the system due to uncertainties such as external disturbances. First, the boundedness and stability of the designed controller are proved by applying the Lyapunov function. Then, the effectiveness of the designed controller for trajectory tracking in position servoing is numerically simulated using MATLAB software. Finally, in this paper, the experimental equipment is used to build a test platform for joint control of a robot, and the proposed controller is verified experimentally, which confirms the efficiency and stability of the designed controller after the experimental comparison and analysis with some other control algorithms.