Stably inverting a dynamic system model is fundamental to subsequent servo designs.Current inversion techniques have provided effective model matching for feedforward controls.However,when the inverse models are to be...Stably inverting a dynamic system model is fundamental to subsequent servo designs.Current inversion techniques have provided effective model matching for feedforward controls.However,when the inverse models are to be implemented in feedback systems,additional considerations are demanded for assuring causality,robustness,and stability under closed-loop constraints.To bridge the gap between accurate model approximations and robust feedback performances,this paper provides a new treatment of unstable zeros in inverse design.We provide first an intuitive pole-zero-map-based inverse tuning to verify the basic principle of the unstable-zero treatment.From there,for general nonminimum-phase and unstable systems,we propose an optimal inversion algorithm that can attain model accuracy at the frequency regions of interest while constraining noise amplification elsewhere to guarantee system robustness.Along the way,we also provide a modern review of model inversion techniques.The proposed algorithm is validated on motion control systems and complex high-order systems.展开更多
垂直起降(Vertical takeoff and landing,VTOL)飞行器是具有3个自由度、2个控制输入的非线性欠驱动控制系统,为了解决严重耦合的VTOL欠驱动系统的输出跟踪问题,首先将VTOL动力学模型解耦成一个最小相位系统和一个非最小相位系统,然后分...垂直起降(Vertical takeoff and landing,VTOL)飞行器是具有3个自由度、2个控制输入的非线性欠驱动控制系统,为了解决严重耦合的VTOL欠驱动系统的输出跟踪问题,首先将VTOL动力学模型解耦成一个最小相位系统和一个非最小相位系统,然后分别针对这两个解耦子系统设计滑模控制器,并通过Lyapunov理论证明系统的稳定性,最后仿真结果表明所设计的滑模控制器实现了对轨迹的无稳态误差跟踪,具有较好的鲁棒性,能够为此类欠驱动系统的输出跟踪问题提供设计参考。展开更多
基金supported in part by the National Science Foundation(1953155)。
文摘Stably inverting a dynamic system model is fundamental to subsequent servo designs.Current inversion techniques have provided effective model matching for feedforward controls.However,when the inverse models are to be implemented in feedback systems,additional considerations are demanded for assuring causality,robustness,and stability under closed-loop constraints.To bridge the gap between accurate model approximations and robust feedback performances,this paper provides a new treatment of unstable zeros in inverse design.We provide first an intuitive pole-zero-map-based inverse tuning to verify the basic principle of the unstable-zero treatment.From there,for general nonminimum-phase and unstable systems,we propose an optimal inversion algorithm that can attain model accuracy at the frequency regions of interest while constraining noise amplification elsewhere to guarantee system robustness.Along the way,we also provide a modern review of model inversion techniques.The proposed algorithm is validated on motion control systems and complex high-order systems.
文摘垂直起降(Vertical takeoff and landing,VTOL)飞行器是具有3个自由度、2个控制输入的非线性欠驱动控制系统,为了解决严重耦合的VTOL欠驱动系统的输出跟踪问题,首先将VTOL动力学模型解耦成一个最小相位系统和一个非最小相位系统,然后分别针对这两个解耦子系统设计滑模控制器,并通过Lyapunov理论证明系统的稳定性,最后仿真结果表明所设计的滑模控制器实现了对轨迹的无稳态误差跟踪,具有较好的鲁棒性,能够为此类欠驱动系统的输出跟踪问题提供设计参考。