气动人工肌肉驱动单关节机械臂的自抗扰控制

针对气动人工肌肉驱动单关节机械臂存在严重的非线性问题,提出一种自抗扰控制策略,来改善单关节机械臂的控制效果。对于给出的不精确系统模型,首先利用跟踪微分器安排输入信号的过渡过程,从而有效地解决了系统的快速性和超调之间的矛盾;其次利用扩张状态观测器观估计出系统状态以及系统的非线性和外部扰动,并对其进行补偿;最后设计了带扩张状态补偿的非线性误差反馈控制器来保证系统的闭环响应性能。实验结果表明,该控制方法在气动单关节机械臂关节关节角度控制方面具有良好的控制效果。

An Active Disturbance Rejection Control Approach for One-DOF Manipulator Driven by Pneumatic Artificial Muscles

An active disturbance rejection control approach is proposed to improve the control accuracy of a one-DOF pneumatic manipulator for strong nonlinear problems caused by the compressibility of air. Based on an inaccurate system model, a tracking differentiator is adopted to arrange the transition process to solve the contradiction between rapidity and overshoot phenomenon for an input signal. Then, an extended state observer is designed to observe not noly the system states, but also the nonlinearity and external disturbance of the system. Lastly, a nonlinear error feedback controller combined with the observation of the extended state is designed to guarantee the control performances of the closed-loop system. For the one-DOF manipulator system, the experimental results prove the validity and advantages of the proposed method.