为解决末端具有不确定负载的柔性机械臂的位置控制问题,设计了自适应自抗扰控制器.采用奇异摄动理论将多柔性连杆机械臂动力学系统分解为快时标和慢时标两个子系统.针对快时标子系统设计线性二次型控制器,用于快速抑制柔性连杆的振动,将快时标状态变量转移到慢流形上;针对慢时标子系统,设计自抗扰控制器,用于跟踪期望角度.针对末端负载的不确定性,采用迭代最小二乘算法估计末端负载的质量,并在自抗扰控制器中进行补偿.结果表明:末端负载的不确定量达到预估负载质量的200%时,在15 rad/s范围内,角度控制的均方差0.08 rad,明显优于不对末端负载进行补偿的情况.在末端负载和机械臂运动速度都发生变化时,所提出的自适应自抗扰控制器具有一定的鲁棒性.%An adaptive active disturbance rejection control is proposed for flexible manipulators with uncertain payload. The two-time scale model of the multiple-flexible-link manipulator is derived via singular perturbation technique. For the fast subsystem, a linear quadratic regulator controller is designed. It depresses the oscillation of flexible links and drives the states to the slow manifold quickly. For the slow subsystem, an adaptive active disturbance rejection controller is proposed to track the desired angular position. A recursive least-squares algorithm is utilized to estimate the payload mass and compensate for the uncertainty. Simulation results show that the mean squire error is less than 0.08 rad even when the payload uncertainty up to 200%of the pre-estimation of the payload mass, which is superior to the case without compensation for the payload uncertain. Thus, the proposed control scheme guarantees a robust performance in presence of uncertain payload and under different maneuver speeds.
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