多自由度电动静液驱动机械臂轨迹跟踪控制

Trajectory tracking control of multi-degree-of-freedom electro-hydrostatic driving manipulator

液压机械臂相比于电动机械臂在重载搬运领域具有不可替代的优势,而多自由度液压机械臂强耦合、本质非线性和模型不确定的特点,给高精度轨迹跟踪控制带来挑战。以多自由度电动静液驱动机械臂为对象,提出一种轨迹跟踪控制策略。首先,建立含电动静液作动器动态的多自由度机械臂动力学模型;其次,基于反步思想设计控制器,并且通过Lyapunov分析证明了系统稳态性;最后,以三自由度电动静液驱动机械臂为例,搭建AMESim-Simulink联合仿真模型,选取3种控制器对比机械臂各关节轨迹的跟踪精度。2种跟踪指令验证结果表明:相较C3控制器和C2控制器,所设计的C1控制器可以较好地补偿机械臂动态,使机械臂各关节更好地跟踪期望轨迹,本研究可为多自由度电动静液驱动机械臂的控制策略设计提供参考。

Compared with electric manipulator,hydraulic manipulator has irreplaceable advantages in the field of heavy load handling.However,the characteristics of strong coupling,intrinsic nonlinearity and model uncertainties bring challenges to high-precision trajectory tracking control of multi-degree-of-freedom hydraulic manipulator.A control strategy for trajectory tracking for multi-degree-of-freedom electro-hydrostatic driving manipulator is proposed in the paper.Firstly,the dynamic model of the multi-degree-of-freedom manipulator with electro-hydrostatic actuator dynamic is established.Secondly,the controller is proposed based on the backstepping,and the stability is proved via Lyapunov analysis.Finally,the 3-DOF electro-hydrostatic driving manipulator is chosen as the application case.The co-simulation model based on AMESim-Simulink is built,and three controllers are selected to compare the trajectory tracking accuracy of each joint of the manipulator.The verification results under two desired trajectories show that compared with C3 controller and C2 controller.The proposed controller can compensate the dynamic of the manipulator well,enable the joints of the manipulator to better track the desired trajectory.This research can provide reference for the design of control strategy for multi-degree-of-freedom electro-hydrostatic driving manipulator.