工作空间机器人末端轨迹的滑模控制

Study on trajectory of manipulators end-effector based on sliding mode algorithm in task space

为了提高工业机器人轨迹跟踪性能,针对传统控制器存在的启动输出转矩大、误差收敛速度慢和抖振等问题,提出了一种应用于机器人工作空间的基于改进型双幂次指数趋近律的滑模控制律设计方法。在工作空间位置坐标的动力学方程基础上,通过改进指数趋近律的方法,将基于饱和函数的双幂次指数趋近律运用在终端滑模控制器设计中,实现了对工作空间下末端轨迹的直接控制,在Simulink环境下对比分析了两种趋近律设计滑模控制律的控制效果。结果表明:基于该方法所设计的控制器具有良好的鲁棒性和控制精确度,同时有效地削弱了抖振。

This paper presents a novel design approach for sliding mode control law based on an improved double power exponential reaching law a method aimed at improving the trajectory tracking performance of industrial robot as a viable solution to the drawbacks inherent in traditional controllers, such as a higher starting output torque, a lower error convergence speed and chattering. The research building on the dynamics equations in task space coordinates involves improving exponential reaching law and applying the double power exponential reaching law with the saturation function for designing a termi- nal sliding mode controller; and thereby achieving the direct control of end-effector＇ s trajectory in task space. The study is validated by the simulation experiment under the environment of Simulink and subsequent comparison of the control effects of different controllers under two reaching laws. The results demonstrate that this proposed method may provide a control system with a better robustness, a greater control precision, and an effective chattering reduction.