基于三步法的机械臂轨迹跟踪控制

考虑机械臂末端轨迹跟踪控制问题,以跟踪逆运动学求解出的末端期望轨迹对应的各关节期望角度为控制目标.设计了一种基于三步法的控制器,该控制器由类稳态控制、可变参考前馈控制和误差反馈控制3部分组成.证明了该控制器可以通过控制机械臂的各关节力矩实现各关节实际角度对期望角度的状态跟踪,进而使得末端轨迹渐近跟踪期望轨迹,并且跟踪误差是输入到状态稳定的.仿真表明基于三步法控制器的空间机械臂末端可以渐近跟踪期望轨迹,并且该算法可以克服系统的末端负载质量变化等不确定性的影响.

Trajectory tracking control of manipulators with triple-step method

Task trajectory tacking control of robot manipulators is considered in this paper. Firstly, task space trajectory tacking problem is transformed into the expected angular tracking problem accordingly in terms of inverse kinematics of robot manipulators. Triple-step method is adopted as the control scheme which consists of a quasi-steady state control, a variable reference feedforward control and an error feedback control. The actual angle of each joint can track asymptotically the expected angle by regulation of the torque of each joint of the robot manipulators, thus the end trajectory can track asymptotically the desired trajectory. Define the deviation between the actual angle and the expected angle of each joint as the error. It is proved that the error system is input-to-state stable. Simulation results show that the end of robot manipulator can track the desired trajectory with a high precision and the system under control is robust to the load changes at the end of robot manipulators.