一种离散的模块化机械臂分布式自抗扰控制策略

A Distributed Discrete Control Strategy with Active Disturbance Rejection Controller for Modular Manipulators

针对模块化机械臂动力学中存在的参数不确定性及外界干扰,在参考输入受噪声影响的情况下,提出了一种离散时间模块化机械臂关节空间分布式控制策略。利用跟踪微分器获得了高质量的角位移信号及其微分信号,利用扩张状态观测器来补偿机械臂不确定非线性动力学以及外部干扰,并采用非线性状态误差反馈形成控制作用,在关节空间设计强鲁棒性的自抗扰控制器实现机械臂关节空间的轨迹跟踪控制。由于对每个关节单独设计了控制器,因此控制器结构简单,易于实现,仿真结果进一步验证了所提方案优于传统控制方法。

A distributed discrete control strategy for modular manipulator joint space control is brought forward,under the condition that there are parameter uncertainties and external disturbance ,as well as the reference is disturbed by noise. In this control strategy, the high quality joint displacement signal and its differential coefficient can be obtained via the tracking differentiator, and the extended state observer can be taken to compensate the nonlinear uncertain dynamics and external disturbance,therefore the strong robust active disturbance rejection controller for joint space trajectory tracking can be designed through the nonlinear state error feedback. Because the controller is designed for each joint separately, the structure is simple and easy to implement,and the simulation results further validate that the proposed strategy is better than the traditional control methods.