Simulation-Based Novel Hybrid Proportional Derivative/H-Infinity Controller Design for Improved Trajectory Tracking of a Two-Link Robot Arm

Abstract

A hybrid control strategy integrating proportional derivative (PD) and the H-infinity control methodology is proposed for a serial two-link robotic manipulator with the goal of improving the tracking performance of the robot arm. The H-infinity controller has the ability to achieve a high performance and robustness in the presence of disturbances and uncertainties, while the PD controller is effective in stabilizing the manipulator. Simulation results using Matlab and Simulink show that the proposed hybrid controller, which integrates the advantages of both PD and H-infinity controllers, has the lowest rise time for the second link, the lowest settling time for the two links, the lowest peak time for both links, and the fastest decay of the error response. In addition, the hybrid control scheme also has the lowest mean square error value, with a 53.3% improvement over the H-infinity controller and a 91.8% improvement over the PD controller, indicating an improved trajectory tracking performance when compared with pure PD and pure H-infinity controllers, respectively. It was also found that the hybrid controller has the lowest integral absolute error, integral square error, integral time absolute error, and integral time square error for the second link, while the error values for the first link are satisfactory, showing a superior performance of the hybrid controller above the PD and H-infinity controllers, respectively.

摘要

为提高串联双连杆机器人手臂的跟踪性能, 提出了一种将比例导数(PD)和H_∞控制方法相结合的混合控制策略。H_∞控制器能够在存在干扰和不确定性的情况下实现高性能和鲁棒性, 而PD控制器在稳定机械臂方面是有效的。Matlab 和Simulink 仿真结果表明, 该混合控制器综合了PD 控制器和H_∞控制器的优点, 具有在第二连杆上升时间最短、两连杆稳定时间最短、两连杆峰值时间最短、误差响应衰减最快的特点。此外, 混合控制方案的均方误差值也最低, 比H_∞控制器提高了53.3%, 比PD 控制器提高了91.8%, 表明了与纯PD 和纯H_∞控制器相比, 混合控制方案的轨迹跟踪性能有所提高。第二连杆的积分绝对误差、积分**方误差、积分时间绝对误差和积分时间**方误差最小, 而第一连杆的误差值令人满意, 表明混合控制器的性能分别优于PD 和H_∞控制器。