对存在摩擦干扰力矩的自由漂浮空间机械臂任务空间路径跟踪控制问题采用终端滑模,实现了跟踪误差的有限时间镇定.同时考虑执行机构存在的死区特性,设计了自适应补偿机构,通过自适应控制来学习死区特性的上界,以确保跟踪控制的有效执行.最后基于Lyapunov方法,从理论上证明了闭环系统的全局稳定性,并通过数值仿真证明此控制器能够有效实现任务空间路径跟踪控制,且对干扰具有一定的鲁棒性.
The tracking problem of free-floating space manipulator system in task space with friction disturbance torque is investigated in this paper.A terminal sliding mode controller is proposed to achieve finite time stabilization of the system.Furthermore,taking into account the existence of dead-zone nonlinearity of the actuator,an adaptive compensator is designed to estimate its upper bound and thus ensure the effectiveness of the proposed controller.Lyapunov stability analysis proves that the closed-loop system is globally asymptotic stable.Numerical simulations show that this controller can effectively achieve inertia space tracking task and also be robust to external disturbances.