轮式机器人移动过程中滑模控制策略的研究

Research on Sliding Mode Control Strategy of Wheeled Robot in Moving Process

针对移动机器人的路径跟踪控制问题,提出了一种全局稳定定理与指数趋近律相结合的滑模控制方法。在控制器的设计中,定义了惯性坐标系和机器人坐标系,建立移动机器人运动模型,标定出位置误差和姿态角误差;基于指数趋近律设计了移动机器人的轨迹跟踪控制器,利用全局稳定定理改进了控制器的控制律算法,通过Lyapunov函数证明了控制器的稳定性;最后采用双环闭环控制结构对此路径跟踪系统进行了MATLAB仿真,并与传统指数控制律设计的控制器进行对比。结果表明,该方法提高了机器人在路径跟踪过程中线速度与角速度的稳定性,削弱了指数控制律的抖振现象,验证了新指数控制律设计的轨迹跟踪控制器的可行性与有效性。

Aiming at solving the problem of path tracking control of mobile robot,a sliding mode control method is proposed combined with global stability and exponential reaching law.In the design of the controller,the inertial coordinate system and robot coordinate system are dfined firstly.The kinematic model of mobile robot is developed,the position error and attitude angle error are calibrated.The path tracking controller for mobile robots is designed by the exponential reaching law,and the control law algorithm is improved by global stability theorem,and Lyapunov function is used to prove the controller stability.Finally,the double closedloop control structure is used to simulate the path tracking system in MATLAB,and the comparison is made with the controller designed by the traditional exp-onential control law.The results show that the stability of linear velocity and angular velocity of the robot in the path tracking process is improved and the chattering of exponential control law is weakened by the proposed method.The feasibility and effectiveness of the pathing tracking controller designed by the new exponential control law are verified.