基于终端滑模的多关节机器人跟踪控制

针对具有不确定性干扰的多关节机器人系统的轨迹跟踪控制问题,利用终端滑模控制方法,给出了全局有限时间跟踪控制器设计;首先,根据多关节机器人动力学模型的特点,基于非奇异终端滑模控制技术并利用滑模设计思想,设计了轨迹跟踪滑模控制器;在该控制器的作用下,跟踪误差不仅能够在有限时间内从任意初始状态到达滑动面,而且也能在有限时间内沿着滑模收敛到原点;其次,由于所设计的控制器的非连续性,将会使得系统产生抖振现象;针对这个问题,利用修正的饱和函数来代替控制律中的符号函数,从而消除了系统的抖振问题;最后,仿真算例表明了该方法的有效性。

Tracking Control of Multi-linked Robots Based on Terminal Sliding Mode

For the trajectory tracking control problem of multi-linked robots with uncertain disturbances,a global finite-time tracking controller is proposed based on terminal sliding mode control method.Firstly,according to the features of dynamic model of multi-linked robots,the trajectory tracking sliding mode controller is designed based on nonsingular terminal sliding mode control technology and sliding mode design theory.Under the action of the designed controller,the tracking error not only reaches the terminal sliding mode surface from any initial states but also converges to the origin along the sliding mode surface in finite time.Secondly,due to the non-linear continuity of the controller,the chattering phenomenon occurs.To this phenomenon,a modified saturation function is utilized to substitute the sign function in the designed controller,and thus the chattering can be eliminated.Finally,simulation results verify the effectiveness of this method.