刚柔耦合机械臂的滑模预测振动控制研究

Research on Sliding Mode Predictive Vibration Control of Rigid-flexible Coupled Manipulators

针对刚柔耦合机械臂动力学模型的非线性、强耦合、时变问题,提出一种滑模预测控制方法可有效降低柔性臂的末端振动,同时提高末端轨迹跟踪性能和运动精度。首先采用输出重定义法得到柔性臂末端的观测量,将内动态子系统转换为零动态子系统,抑制柔性臂末端的振动;预测作为跟踪误差及其高阶导数组合的滑模面,将滑模面引入到预测控制的二次性能指标中,根据预测模型预估系统未来的输出,消除末端控制误差,并通过稳定性分析论证控制器的稳定性。最后通过仿真和实验验证该方法的有效性,证明其可提高刚柔耦合机械臂的运动精度。

Aiming at the problems of the nonlinear,strong coupling,and time-varying of the dynamic model of the rigid-flexible coupling manipulator,a sliding mode predictive control method is proposed to effectively reduce the end vibration of the flexible manipulator,and then improve the end trajectory tracking performance and motion accuracy.Firstly,the output redefinition method is used to obtain the observations of the end of the flexible manipulator,and the internal dynamic subsystem is converted to a zero dynamic subsystem to suppress the vibration of the end of the flexible manipulator.The sliding mode surface of the tracking error and its high-order derivative combination is predicted and introduced into the secondary performance index of the predictive control.The future output of the system is estimated through the predictive model to eliminate the end control error.The stability of the controller is demonstrated through stability analysis.Finally,the effectiveness of the method is verified by simulation and experiment,and the motion accuracy of the rigid-flexible coupling manipulator is improved.