RISE-Based Adaptive Asymptotic Tracking Control of Space 3-DOF Manipulators with Hydraulic Actuators

Abstract

Robotic arms play an irreplaceable and important role in the development trend of automation in all walks of life. Among them, the hydraulic driven manipulator is more widely used in the field of heavy-duty engineering due to its own advantages. However, since the coriolis force, centrifugal force, gravity, etc. will change to varying degrees during the simultaneous movement of each joint, and the end positioning accuracy of the manipulator is difficult to reach a high level. Therefore, considering the complexity of the manipulator dynamics model and the variability of the task, how to improve the joint tracking accuracy of the manipulator has become a major problem. In this paper, the hydraulic manipulator with space 3-DOF is taken as the research object. The manipulator has one rotary joint and two pitching joints, among which the rotary joint is driven by a hydraulic rotary actuator and the pitching joint is driven by a hydraulic cylinder. The robust integral of the sign of the error (RISE) controller is used to design the control law to suppress the influence of disturbances and various uncertainties, and the gain adaptive rate of the controller is designed based on the adaptive theory to achieve the purpose of self-tuning the controller parameters. Based on Lyapunov stability theory, it can be seen that the proposed control strategy can achieve higher tracking performance and the asymptotic stability. The comparative simulations shows that the proposed control method can significantly improve the tracking performance of each joint.