双臂柔性机械手的终端滑模控制

提出一种用于双臂柔性机械手系统的终端滑模控制方法，以解决其非最小相位控制问题．重新定义了柔性机械手系统的输出，通过输入输出线性化，将系统分解为输入输出子系统和内部子系统．设计逆动态终端滑模控制策略，使输入输出子系统在有限时间内收敛到零；选择适当的控制器参数，使零动态子系统在平衡点附近渐近稳定，从而保证整个系统的渐近稳定．仿真结果证明了该设计方法的有效性．     

参数不确定柔性机械手的终端滑模控制

针对参数不确定双臂柔性机械手系统, 提出一种基于遗传算法的终端滑模控制方法, 以实现其末端控制.基于输出重定义方法, 通过输入输出线性化, 将系统分解为输入输出子系统和内部子系统. 设计终端滑模控制策略,使输入输出子系统有限时间内收敛到零, 内部子系统变为零动态子系统; 采用遗传算法优化零动态子系统参数, 使其在平衡点附近渐近稳定. 根据Lyapunov稳定性理论算出末端输出位移的误差范围. 仿真结果证明该方法有效性.     

非匹配不确定系统的终端滑模分解控制

针对非匹配多变量模型不确定系统,提出了一种终端滑模分解控制方法.通过状态变换和去耦合处理将系统转换为块能控标准型,它由匹配扰动的值域空间子系统和稳定的非匹配扰动的零动态子系统组成.提出了特殊的终端滑模超曲面,采用滑模控制策略,使值域空间子系统的状态在有限时间内收敛至平衡点,随后非匹配扰动的零动态子系统渐近收敛至平衡点附近的邻域内,且建立了该邻域的范围与系统的非匹配不确定性范围之间的数学关系,并用于系统的设计与分析.所提方法对于维数较高的非匹配不确定系统的控制具有较大的意义,可简化设计,实现递阶控制.仿真实     

多变量线性模型不确定系统终端滑模分解控制方法

针对线性多变量模型不确定系统系统,提出了一种终端滑模分解控制方法.通过状态变换和去耦合处理将系统转换为块能控标准型,它由值域空间子系统和稳定的零空间子系统组成.提出了特殊的终端滑模超曲面,采用滑模控制策略,使值域空间子系统的状态在有限时间内收敛至平衡点,随后稳定的零空间子系统渐近收敛至平衡点.所提出的方法对于维数较高系统的控制具有较大意义,可简化设计,实现递阶控制.仿真验证了该方法的有效性.     

参数不确定柔性机械手的快速终端滑模控制

针对具有参数不确定性的柔性机械手,采用重新定义系统输出的方法,将系统分解为输入输出子系统和零动态子系统.对于输入输出子系统提出了一种递阶快速终端滑模控制策略,使得输入输出子系统在有限时间内收敛.将零动态子系统在平衡点近似线性化以选择控制器的设计参数,使零动态子系统在平衡点附近渐近稳定,从而保证了整个柔性机械手系统的渐近稳定,对系统中的不确定性具有较强的鲁棒性.仿真结果验证了所提方法的正确性.     

柔性机械手的鲁棒控制器设计

针对柔性机械手的动力学方程具有非最小相位的特点，运用重新定义的柔性机械手系统的输出，通过输入输出线性化，将系统分解为输入输出子系统和零动态子系统．考虑到柔性机械手系统存在的不确定性，设计终端滑模控制器，使输入输出子系统在有限时间内收敛到零．最优组合输出系数采用混沌遗传算法优化，以保证零动态子系统在平衡点附近渐近稳定，从而保证整个系统渐近稳定．仿真结果证明了设计方法的有效性．     

基于混沌遗传算法的柔性机械手滑模控制器优化设计

针对柔性机械手动力学方程的非最小相位特点,本文提出一种柔性机械手的终端滑模控制方法,将关节电机转角和柔性模态变量的线性组合定义为柔性机械手系统的输出.通过输入输出线性化,将系统分解为输入输出子系统和零动态子系统.设计终端滑模控制策略,使输入输出子系统在有限时间收敛到零;利用混沌遗传算法优化控制器的设计参数,使零动态了系统在甲衡点附近渐近稳定,从而保证整个系统的渐近稳定.本文提出的方法设计过程简单,易于实现.仿真结果证明了设计的有效性.     

基于鲁棒滑模观测器的两关节柔性机械手控制

柔性机械手系统为非最小相位系统, 当控制有界时, 该特性阻碍其端点位移渐近跟踪期望轨迹. 本文首先重新定义柔性机械手系统的输出, 通过输入输出线性化, 将系统分解为输入输出子系统和零动态子系统; 然后提出一种用于观测柔性模态导数的鲁棒滑模观测器, 使状态估计达到预期的指标, 解决了柔性模态导数难以获得的问题; 设计积分滑模控制策略, 使输入输出子系统在有限时间收敛到零; 选择适当的控制器参数, 使零动态子系统在 平衡点附近渐近稳定, 从而保证整个系统的渐近稳定. 本文提出的方法设计过程简单, 易于实现. 仿真结果证明了设计的有效性.     

基于线性化法柔性机械臂控制器的设计

利用输入输出线性化的方法，柔性机械臂的模型可分解为两个子系统：输入输出子系统和零动态子系统。输入输出子系统采用模糊控制。通过分析零动态子系统特征值和重新定义的系统输出中的设计参数之间的关系，确定设计参数，并使得零动态子系统渐近稳定于平衡点．从而保证整个系统渐近稳定。     

快速非奇异终端滑模在混沌系统中的应用

为解决传统线性滑模控制中的速度较慢和终端滑模的奇异性问题,提出一种快速非奇异终端滑模的控制策略,并将其应用于Lorenz混沌系统中。控制策略为当系统状态离平衡点较远时采用线性滑模,使其快速地到达滑模面;而一旦滑模到达所设计的滑模面时控制策略变为非奇异终端滑模,使其快速地收敛于平衡点。此策略将线性滑模和终端滑模的优点相结合,从而使整个系统的状态在全程都具有较快的收敛速度,此方法改善了传统的线性滑模只能渐近地趋近于平衡点的动态缺点;同时也改善了单独采用终端滑模时,离平衡点较远的状态到达时间较长的缺点;且有效地避免了奇异现象的发生。最后通过M atlab仿真,对Lorenz混沌系统进行仿真,验证了该方法的有效性。     

SECOND‐ORDER NONSINGULAR TERMINAL SLIDING MODE DECOMPOSED CONTROL OF UNCERTAIN MULTIVARIABLE SYSTEMS

This paper proposes a second‐order nonsingular terminal sliding mode decomposed control method for multivariable linear systems with internal parameter uncertainties and external disturbances. First, the systems are converted into the block controllable form, consisting of an input‐output subsystem and a stable internal dynamic subsystem. A special second‐order non‐singular terminal sliding mode is proposed for the input‐output subsystem. The control law is designed to drive the states of the input‐output subsystem to converge to the equilibrium point asymptotically. Then the states of the stable zero‐dynamics of the system converge to the equilibrium point asymptotically. The method proposed in the paper has advantages for higher‐dimensional multivariable systems, in the sense that it simplifies the design and makes it possible to realize a robust decomposed control. Meanwhile, because of the adoption of the second‐order sliding mode, the control signal is continuous. Simulation results are presented to validate the design.     

Second-order terminal sliding mode control of uncertain multivariable systems

A second-order terminal sliding mode controller for uncertain multivariable systems is proposed in this paper. The controller adopts the hierarchical control structure. The paper derives the state transform matrices which are used to transform a multivariable linear system to the block controllable form consisting of two subsystems, an input–output subsystem and a stable internal dynamic subsystem. The proposed controller utilizes a non-singular terminal sliding mode manifold for the input–output subsystem to realize fast convergence and better tracking precision. Meanwhile, a chattering-free second-order terminal sliding mode control law is presented. The stability of uncertain multivariable systems can be realized using the proposed controller. A derivative estimator is utilized in the paper to estimate the derivatives of the sliding mode functions for the controller. The simulation results are presented to validate the design method.     

A multitask sliding mode control for mismatched uncertain large-scale systems

A new sliding mode control (SMC) approach, output variables only, single phase only and chattering phenomenon free, is presented for a class of mismatched uncertain large-scale systems. For a new multitask SMC, it is not required that the system states are available. Moreover, the sliding function in this study just depends on output variables. Using an exponential type sliding surface, the system states are always in the sliding mode at the beginning time t = 0. Using a newly appropriate linear matrix inequality stability conditions by the Lyapunov method are derived such that each subsystem in the new sliding mode is completely invariant to matched uncertainties. As a result, robustness of the mismatched uncertain large-scale systems can be assured throughout an entire response of the system starting from the initial time t = 0. In every subsystem, a scheme of decentralised control using only output states is proposed. In addition, a continuous controller is finally designed for chattering removal. Finally, a numerical example is used to demonstrate the efficacy of the proposed method.     

Adaptive sliding mode trajectory tracking control for wheeled mobile robots

This paper discusses the problem of adaptive sliding mode trajectory tracking control for wheeled mobile robots in the presence of external disturbances and inertia uncertainties. A new fast nonsingular terminal sliding mode surface without any constraint is proposed, which not only avoids singularity, but also retains the advantages of sliding mode control. In order to implement the trajectory tracking mission, the error dynamic system is divided into a second-order subsystem and a third-order one. First, an adaptive fast nonsingular terminal sliding mode control law of the angular velocity is constructed for stabilising the second-order subsystem in finite time. Then, another adaptive fast nonsingular terminal sliding mode control law of the linear velocity is designed to guarantee the stability of the third-order subsystem. Finally, a simulation example is provided to demonstrate the validity of the proposed control scheme.