A prescribed performance control scheme based on the three-inflection-point hyperbolic function and predefined time performance function is proposed to solve the trajectory tracking problem of the forward-tilting morp...A prescribed performance control scheme based on the three-inflection-point hyperbolic function and predefined time performance function is proposed to solve the trajectory tracking problem of the forward-tilting morphing aerospace vehicle with time-varying actuator faults.To accurately estimate the loss degree of actuator faults,an immersion and invariance observer based on the predefined time dynamic scale factor is designed to estimate and compensate it.A composite dynamic sliding mode surface is designed using a three-inflection-point hyperbolic function,and a novel three-inflection-point sliding mode control framework is proposed.The convergent domain of the sliding manifold is adjusted by parameters,and the system error convergence is controllable.A transfer function is designed to eliminate the sensitivity of the three-inflection-point hyperbolic sliding mode to the unknown initial state,and combined with the barrier Lyapunov function,and the performance constraint of the system is realized.The global asymptotic stability of the system is demonstrated using a strict mathematical proof.The effectiveness and superiority of the proposed control scheme are proven by simulation experiments.展开更多
Structural nonlinearities such as freeplay will affect the stability and even flight safety of the fin-actuator system.There is a lack of a practical method for designing Active Flutter Suppression (AFS) control laws ...Structural nonlinearities such as freeplay will affect the stability and even flight safety of the fin-actuator system.There is a lack of a practical method for designing Active Flutter Suppression (AFS) control laws for nonlinear fin-actuator systems.A design method for the AFS controller of the nonlinear all-movable fin-electromechanical actuator system is established by combining the inverse system and the Immersion and Invariance (I&I) theory.First,the composite control law combining the inverse system principle and internal model control is used to offset the nonlinearity and dynamics of the actuator,so that its driving torque can follow the ideal signal.Then,the ideal torque of the actuator is designed employing the I&I theory.The unfavorable oscillation of the fin is suppressed by making the output torque of the actuator track the ideal signal.The simulation results reveal that the proposed AFS method can increase the flutter speed of the nonlinear finactuator system with freeplay,and a set of controller parameters is also applicable for wider freeplay within a certain range.The power required for the actuator does not exceed the power that can be provided by the commonly used aviation actuator.This method can also resist a certain level of noise and external disturbance.展开更多
针对双关节机械臂在运动过程中因系统不稳定所产生的跟踪精度较低问题,设计了基于浸入与不变(Immersion and Invariance,I&I)的机械臂运动轨迹自适应控制系统,采用I&I自适应控制方法作为惯性矩阵设计参数估计器。为了解决设计...针对双关节机械臂在运动过程中因系统不稳定所产生的跟踪精度较低问题,设计了基于浸入与不变(Immersion and Invariance,I&I)的机械臂运动轨迹自适应控制系统,采用I&I自适应控制方法作为惯性矩阵设计参数估计器。为了解决设计过程中偏微分方程求解困难,选用状态滤波器求出其近似解。通过引用动态缩放因子消除近似解和真实解之间的误差。将I&I自适应参数估计器与反步控制器相结合,使其对不确定参数具有自适应特征。仿真结果表明,本方案对机器人机械臂运行轨迹的控制精度有显著提高,具有一定的应用价值。展开更多
为实现欠驱动四旋翼飞行器的位置及偏航渐近跟踪,本文基于浸入和不变技术(immersion and invariance,I&I)提出非线性跟踪控制方法.针对四旋翼飞行器的欠驱动特性,设计了内/外环分别为姿态和位置的双闭环结构,并采用浸入和不变技术...为实现欠驱动四旋翼飞行器的位置及偏航渐近跟踪,本文基于浸入和不变技术(immersion and invariance,I&I)提出非线性跟踪控制方法.针对四旋翼飞行器的欠驱动特性,设计了内/外环分别为姿态和位置的双闭环结构,并采用浸入和不变技术构建内/外环的稳定跟踪控制器,利用李雅普诺夫定理保证闭环系统的渐近稳定性.最后,在MATLAB/Simulink环境下进行数值仿真,验证了I&I控制方案的有效性.展开更多
针对水轮机调节系统簇发振荡的抑制问题,提出一种基于浸入与不变(immersion and invariance, I&I)原理的自适应反步滑模控制策略。首先,建立两时间尺度下的水轮机调节系统动力学模型,并分析系统的簇发振荡行为;其次,结合反步理论和...针对水轮机调节系统簇发振荡的抑制问题,提出一种基于浸入与不变(immersion and invariance, I&I)原理的自适应反步滑模控制策略。首先,建立两时间尺度下的水轮机调节系统动力学模型,并分析系统的簇发振荡行为;其次,结合反步理论和基于趋近律的滑模原理设计控制器,同时,对水轮机调节系统在运行过程受到的外部扰动,引入I&I理论对扰动估计误差建立流形,通过自适应律的选取保持其吸引与不变,并采用Lyapunov稳定性理论对所提控制方法进行收敛性证明;最后,对上述控制策略进行仿真验证。结果表明,该方法能有效抑制系统的簇发振荡现象,且具有较好的扰动跟踪精度。展开更多
The Immersion and Invariance （I＆I） methodology provides a novel approach for nonlinear system control, which is distinct from the traditional feedback linearization and backstepping method. In this paper, a new exc...The Immersion and Invariance （I＆I） methodology provides a novel approach for nonlinear system control, which is distinct from the traditional feedback linearization and backstepping method. In this paper, a new excitation controller is designed for single machine infinite bus system （SMIBS） based on the I＆I approach. Firstly the dynamic model of SMIBS is homeomorphously transformed to a specific form for which a stable lower-order target system is selected. Then the I＆I excitation controller is designed by immersing the transformed system into the target system. Simulation results from PSCAD/EMTDC demonstrate that the proposed controller guarantees transient stability of the system after large disturbances.展开更多
This paper proposes a robust Immersion and Invariance(I&I)adaptive coordinated controller for a class of uncertain linear-motor-driven biaxial gantry system subject to external disturbances for high-accuracy conto...This paper proposes a robust Immersion and Invariance(I&I)adaptive coordinated controller for a class of uncertain linear-motor-driven biaxial gantry system subject to external disturbances for high-accuracy contour tracking.Firstly,the dynamic model of the gantry system is transformed into task coordinate frame,through which the contour tracking can be regarded as a regulation problem.Based on the transformed system dynamics,an I&I-based adaptation law with smooth projection is proposed to estimate the unknown parameters.Different from traditional adaptive control,the proposed robust I&I adaptive control introduces a new term called tuning function in adaptation law to shape the dynamic behaviour of the estimation vector.Then the stability of the closed-loop system is proved by Lyapunov theory.Finally,comparative experiments are executed on an industrial biaxial gantry system with two different cases to verify the effectiveness of the proposed control law.展开更多
基金co-supported by the Xinjiang Uygur Autonomous Region Natural Science Foundation,China(No.2022D01C86)the National Natural Science Foundation of China(No.62263030)the Open Research Fund Program of Beijing National Research Center for Information Science and Technology,China(No.BR2023KF02011).
文摘A prescribed performance control scheme based on the three-inflection-point hyperbolic function and predefined time performance function is proposed to solve the trajectory tracking problem of the forward-tilting morphing aerospace vehicle with time-varying actuator faults.To accurately estimate the loss degree of actuator faults,an immersion and invariance observer based on the predefined time dynamic scale factor is designed to estimate and compensate it.A composite dynamic sliding mode surface is designed using a three-inflection-point hyperbolic function,and a novel three-inflection-point sliding mode control framework is proposed.The convergent domain of the sliding manifold is adjusted by parameters,and the system error convergence is controllable.A transfer function is designed to eliminate the sensitivity of the three-inflection-point hyperbolic sliding mode to the unknown initial state,and combined with the barrier Lyapunov function,and the performance constraint of the system is realized.The global asymptotic stability of the system is demonstrated using a strict mathematical proof.The effectiveness and superiority of the proposed control scheme are proven by simulation experiments.
文摘Structural nonlinearities such as freeplay will affect the stability and even flight safety of the fin-actuator system.There is a lack of a practical method for designing Active Flutter Suppression (AFS) control laws for nonlinear fin-actuator systems.A design method for the AFS controller of the nonlinear all-movable fin-electromechanical actuator system is established by combining the inverse system and the Immersion and Invariance (I&I) theory.First,the composite control law combining the inverse system principle and internal model control is used to offset the nonlinearity and dynamics of the actuator,so that its driving torque can follow the ideal signal.Then,the ideal torque of the actuator is designed employing the I&I theory.The unfavorable oscillation of the fin is suppressed by making the output torque of the actuator track the ideal signal.The simulation results reveal that the proposed AFS method can increase the flutter speed of the nonlinear finactuator system with freeplay,and a set of controller parameters is also applicable for wider freeplay within a certain range.The power required for the actuator does not exceed the power that can be provided by the commonly used aviation actuator.This method can also resist a certain level of noise and external disturbance.
文摘针对双关节机械臂在运动过程中因系统不稳定所产生的跟踪精度较低问题,设计了基于浸入与不变(Immersion and Invariance,I&I)的机械臂运动轨迹自适应控制系统,采用I&I自适应控制方法作为惯性矩阵设计参数估计器。为了解决设计过程中偏微分方程求解困难,选用状态滤波器求出其近似解。通过引用动态缩放因子消除近似解和真实解之间的误差。将I&I自适应参数估计器与反步控制器相结合,使其对不确定参数具有自适应特征。仿真结果表明,本方案对机器人机械臂运行轨迹的控制精度有显著提高,具有一定的应用价值。
文摘为实现欠驱动四旋翼飞行器的位置及偏航渐近跟踪,本文基于浸入和不变技术(immersion and invariance,I&I)提出非线性跟踪控制方法.针对四旋翼飞行器的欠驱动特性,设计了内/外环分别为姿态和位置的双闭环结构,并采用浸入和不变技术构建内/外环的稳定跟踪控制器,利用李雅普诺夫定理保证闭环系统的渐近稳定性.最后,在MATLAB/Simulink环境下进行数值仿真,验证了I&I控制方案的有效性.
文摘针对水轮机调节系统簇发振荡的抑制问题,提出一种基于浸入与不变(immersion and invariance, I&I)原理的自适应反步滑模控制策略。首先,建立两时间尺度下的水轮机调节系统动力学模型,并分析系统的簇发振荡行为;其次,结合反步理论和基于趋近律的滑模原理设计控制器,同时,对水轮机调节系统在运行过程受到的外部扰动,引入I&I理论对扰动估计误差建立流形,通过自适应律的选取保持其吸引与不变,并采用Lyapunov稳定性理论对所提控制方法进行收敛性证明;最后,对上述控制策略进行仿真验证。结果表明,该方法能有效抑制系统的簇发振荡现象,且具有较好的扰动跟踪精度。
文摘The Immersion and Invariance （I＆I） methodology provides a novel approach for nonlinear system control, which is distinct from the traditional feedback linearization and backstepping method. In this paper, a new excitation controller is designed for single machine infinite bus system （SMIBS） based on the I＆I approach. Firstly the dynamic model of SMIBS is homeomorphously transformed to a specific form for which a stable lower-order target system is selected. Then the I＆I excitation controller is designed by immersing the transformed system into the target system. Simulation results from PSCAD/EMTDC demonstrate that the proposed controller guarantees transient stability of the system after large disturbances.
基金the National Natural Science Foundation of China[Grant Number 61673050].
文摘This paper proposes a robust Immersion and Invariance(I&I)adaptive coordinated controller for a class of uncertain linear-motor-driven biaxial gantry system subject to external disturbances for high-accuracy contour tracking.Firstly,the dynamic model of the gantry system is transformed into task coordinate frame,through which the contour tracking can be regarded as a regulation problem.Based on the transformed system dynamics,an I&I-based adaptation law with smooth projection is proposed to estimate the unknown parameters.Different from traditional adaptive control,the proposed robust I&I adaptive control introduces a new term called tuning function in adaptation law to shape the dynamic behaviour of the estimation vector.Then the stability of the closed-loop system is proved by Lyapunov theory.Finally,comparative experiments are executed on an industrial biaxial gantry system with two different cases to verify the effectiveness of the proposed control law.
