【摘要】 为了抑制柔性机械臂运动过程中的非线性振动，提出一种基于干扰力在线观测的无模型轨迹跟踪和振动抑制混合控制策略。采用拉格朗日方程和奇异摄动法对存在未知干扰的柔性机械臂进行动力学建模和解耦，将其分解为表征刚性运动的慢变子系统和表征柔性振动的快变子系统；考虑到建模的复杂性和模型参数的不确定性，采用PD控制方法实现轨迹跟踪，并提出无模型自适应控制算法以实现柔性臂杆的非线性振动控制。针对未知外界干扰可能引起的控制发散问题，提出了改进的干扰力状态观测器，用于干扰力矩的在线估计和实时补偿，有效提高无模型振动控制算法的收敛性能。仿真试验结果表明，所提算法在存在干扰力的情况下对柔性机械臂的振动抑制效果显著，且具有良好的动态性能和鲁棒性。更多还原

【Abstract】 In order to suppress the nonlinear vibration during the motion of a flexible manipulator, a model-free hybrid control strategy of trajectory tracking and vibration suppression based on a novel online observation of disturb forces is proposed. The Lagrange equation and singular perturbation method are employed to model and decouple the dynamics of the manipulator, which are decomposed into a slow subsystem representing rigid motion and a fast subsystem representing flexible vibration. Considering the complexity of modeling and uncertainty of model parameters, PD control method is adopted to realize trajectory tracking, and modelfree adaptive control algorithm is proposed to realize nonlinear vibration control of flexible links. To solve the control divergence problem caused by unknown external disturb forces, a modified extended state observer is proposed to online estimate and real-time compensate the disturb force, which can improve the convergence performance of model-free vibration control algorithm effectively. The simulation results show that the proposed method can effectively suppress the vibration of the flexible manipulator in the presence of disturb force, and has good dynamic performance and robustness.更多还原