基于干扰观测器的机械臂非线性滑模控制

Nonlinear Sliding Mode Control for Robotic Manipulator Based on Disturbance Observer

针对机械臂在轨迹跟踪时对内部参数扰动及外界干扰较为敏感的特性,设计了一种基于干扰观测器的机械臂非线性滑模控制策略。根据系统动力学模型和Lyapunov稳定性理论,对系统的不确定性和外部干扰采用干扰观测器进行观测,同时设计非线性滑模控制器,构造Lyapunov函数,验证系统的稳定性。在此基础上设计系统控制律,控制律对未观测的干扰进行补偿,保证系统的稳定性,提高机械臂的跟踪性能。仿真结果表明,该策略能较好地克服多种因素引起的干扰,改善系统的控制性能。

A nonlinear sliding mode control strategy of manipulator based on disturbance observer is designed for the characteristics of the manipulator which is sensitive to internal parameter disturbance and the external disturbance in the position tracking.According to the system dynamics model and Lyapunov stability theory, the uncertainties and external disturbances of the system are observed by disturbance observer.At the same time, the nonlinear sliding mode controller is designed and the Lyapunov function is constructed to verify the stability of the system.On this basis, the system control law and the sliding mode control law are designed to compensate the unobserved interference to ensure the stability of the system and improve the tracking performance of the manipulator.The simulation results show that the strategy can overcome the interference caused by many factors and improve the control performance of the system.