考虑齿隙伺服系统的反步自适应模糊控制

Adaptive backstepping fuzzy control for servo systems with backlash

中文关键词  齿隙  近似死区模型  伺服系统  模糊逼近系统  反步自适应控制

英文关键词  backlash  approximate dead-zone model  servo system  fuzzy approximation system  adaptive backstepping control

中文摘要

      针对具有未知参数和齿隙非线性的机电伺服系统, 引入一种近似死区函数建立了系统的数学模型, 给出了死区函数中参数的选取方法. 用两个自适应模糊逻辑系统在线逼近机电伺服系统中的未知参数和非线性环节, 从而避免了对每个未知参数推导自适应律. 基于反步法设计了自适应模糊控制器, 可抑制未知参数和齿隙非线性对系统性能的影响. 采用Lyapunov方法证明了位置跟踪误差的指数收敛性. 与PID控制方法对比的仿真实验表明, 本文方法能够显著减小齿轮间传递力矩的振荡, 并具有很好的控制精度和鲁棒性.

英文摘要

      An approximate dead-zone function is introduced to build the model of the electromechanical servo system with unknown parameters and nonlinear backlash; the method for selecting parameters of the approximate dead-zone function is also given. Two adaptive fuzzy logic systems are employed to approximate unknown parameters and the nonlinear part of the servo system online, to avoid the derivation of adaptive law for each unknown parameter. Adaptive fuzzy controller is also developed based on backstepping method, which effectively inhibits the influence of parameter uncertainties and backlash nonlinearity. It is theoretically shown by using Lyapunov function that the position tracking error converges exponentially. Finally simulations show that the adaptive backstepping fuzzy controller not only reduces gear transmitting torque oscillation significantly, but also have higher accuracy and robustness in performances than PID controller.