机器人的终端滑模变结构控制研究

Research on Terminal Sliding Mode Variable Structure Control for Robots

针对机器人这类非线性强耦合系统,基于滑模变结构控制理论,提出了一种终端滑模变结构控制方法。该方法将系统的状态方程化为为关节子系统,利用终端滑模方法构造每个子系统的滑模面,在此基础上运用李雅普诺夫函数和含有饱和函数的指数趋近律设计了关节子系统的控制律。利用所提出的方法对平面二自由度机器人的控制系统进行了设计并进行了仿真,仿真结果表明了该控制方法不仅有效地实现了机器人关节控制,而且该控制方法还能降低因采用滑模控制而产生的抖振,并使得系统快速收敛到平衡稳定状态。

Base on the sliding mode variable structure control theory, a terminal sliding mode variable algorithm is proposed for robot system which is a nonlinear and strong coupling system. In this algorithm, the systems＇ states equations are divided into joint subsystems, and using the terminal algorithm sliding planes are constructed for each subsystem. Based on these, the Lyapunnv function and exponential approximation law with saturation function are used for the control law of each joint subsystem. Finally, the control law is designed and simulated by proposed algorithm h^r the 2 degrees of freedom horizontal robot, and the simulation results show that the proposed algorithm not only can implement the control of robot joints efficiently, but also can reduce the chattering the caused by using sliding mode variable structure control algorithm and the system can converge to stable very fast.