旋转伺服关节的反馈线性化滑模控制研究

Feedback linearized sliding mode control of rotating servo joints

针对以叶片摆动缸为机器人旋转伺服关节的电液伺服系统中,存在多种非线性因素以及不确定因素扰动的问题,为提高电液伺服系统的控制精度和鲁棒性,提出了一种基于反馈线性化滑模变结构控制理论的控制器。通过对伺服系统非线性模型的建立,利用反馈线性化理论对非线性模型进行了线性化处理;结合滑模变结构控制原理为改进后的系统模型设计了控制器,同时设计了基于模糊自适应PID理论的控制器作为对照模型,通过MATLAB/Simulink模拟了在无干扰、时变负载干扰以及油源油压波动干扰情况下两种控制器驱动的伺服系统,并观测了系统的跟踪特性与稳定性。研究结果表明:相较于模糊自适应PID控制下的伺服系统,基于反馈线性化滑模控制器控制的伺服系统具有更小的跟踪误差、更强的抗干扰能力,可以有效提升伺服系统的鲁棒性。

In order to improve the control precision and robustness of the electro-hydraulic servo system,reduce the influence of nonlinear and uncertain factors,a controller based on the feedback linearization theory of sliding mode variable structure control was proposed.Through the establishment of the nonlinear model of servo system,the nonlinear model was linearized by using the feedback linearization theory.The controller was designed for the improved system model by combining the sliding mode variable structure control principle.At the same time,the controller based on the fuzzy adaptive PID theory was designed as the control model.Through MATLAB/Simulink simulation,the tracking characteristics and stability of the servo system driven by two kinds of controllers were observed under the condition of no disturbance,time-varying load disturbance and oil pressure fluctuation disturbance.The simulation results show that the servo system based on the feedback linearization sliding mode controller has smaller tracking error,stronger anti-interference ability and effectively improves the robustness of the system compared with the servo system under the fuzzy adaptive PID control.