基于扰动观测器的时延双边遥操作系统鲁棒阻抗控制

时延以及不确定性等因素容易造成双边遥操作系统操作性能差,甚至不稳定等问题。为了解决这一问题,针对主、从端不同的任务特点,提出一种新的双边遥操作系统控制结构。由于主端在实现力反馈时易受扰动影响,设计一种非线性扰动观测器用于扰动的在线估计并进行补偿;从端采用基于滑模的阻抗控制以保证精确的位置跟踪和与环境的期望交互。利用Liewellyn绝对稳定准则推导出时延下保证系统稳定性的条件以及参数选取依据。在建立的单自由度遥操作系统试验平台上进行了试验研究,结果表明本文所提方法能够在保证系统鲁棒性的条件下有效提高操作性能。     

面向在轨服务的机器人遥操作双边控制

为解决随机分布时延对双边遥操作系统稳定性的影响,将马尔可夫跳变参数技术应用到时延建模中.首先将遥操作系统的一般方程转化为状态空间描述形式;针对时延的随机分布特征,建立了时延分布的马尔可夫跳变模型;在此基础上,利用线性矩阵不等式方法,构建r系统的时延独立稳定性定理,并用李雅普诺夫函数方法进行了证明;最后,在两种马尔可夫概...     

基于滑模观测器的永磁同步电机无传感器矢量控制

为解决永磁同步电机（PMSM）控制中机械式位置传感器带来的成本及可靠性等问题,将滑模观测器技术应用到PMSM矢量控制系统中。该系统采用滑模面及滑模等效控制方法,通过选择足够大的滑模增益,在观测电流和实测电流之间的误差上构建滑模面,对电机反电势进行观测以得到转子位置角,并基于Lyapunov稳定性判据对滑模观测器的收敛性进行了分析;建立了应用滑模观测器的PMSM无传感器矢量控制实验系统,设计了位置及速度滑模控制器。进行了1500r／min稳态及正负转速切换的角度估算实验,实验结果验证了该方法的有效性。研究结果表明,基于滑模观测器的无传感器控制策略能准确估计出PMSM的转子位置角,从而得到转子速度,且系统具有较好的动、静态特性。     

基于线性矩阵不等式空间遥操作系统的鲁棒H_∞控制

针对具有力反馈空间遥操作系统的时变大时延和环境模型参数不确定问题,提出一种基于线性矩阵不等式(Linearmatrix inequality,LMI)的鲁棒H∞控制方法。对于回路时延是未知时变的遥操作系统,该方法只需要已知时延的上下界,可以解决环境模型参数不确定问题,并获得良好的位置和力跟踪性能。将主从端的动力学模型转化成相应的状态空间方程,并将其离散化、合并为一个离散状态空间方程;然后根据该系统方程,基于LMI方法设计状态反馈控制器,通过定义Lyapunov函数分析闭环系统的稳定性,并且分别给出在环境模型参数确定和不确定情况下,使得闭环系统渐近稳定且满足给定位置跟踪性能的充分条件;仿真试验结果表明所提出的方法可使得遥操作系统渐进稳定且具有好的位置和力跟踪性能。     

基于干扰观测器的AUV垂直面等效滑模控制

为提高欠驱动自主水下机器人在外部干扰影响下的垂直面定深控制性能,设计一种基于干扰观测器的等效滑模控制器。遵循实际状况简化欠驱动自主水下机器人的垂直面模型,通过简化模型建立其状态方程;构造干扰观测器,基于干扰观测器设计系统的等效滑模控制器,根据Lyapunov稳定性理论证明闭环系统的稳定性。仿真结果表明：当存在外部干扰时,该控制器相比传统的滑模控制器能够更好地实现水下机器人的垂直面定深控制,具备良好的抗干扰性能。     

基于虚拟现实的力觉临场感系统及其稳定性分析

时延是影响力觉临场感遥操作系统正常作业的突出问题,而虚拟现实技术是解决时延问题的有力手段.本文通过将虚拟预测环境作为时间前向观测器,构造了基于虚拟现实的力反馈遥操作系统的动力学方程,并在此基础上提出了基于虚拟预测环境误差补偿的控制方法.同时,通过构造了系统的李亚普诺夫函数,对系统的稳定性作了进一步分析.实验结果表明这一方法在保证稳定性的基础上很好的缓解了时延带来的影响,提高了系统的可操作性.     

欠驱动AUV基于干扰观测器的滑模控制

为了提高欠驱动自主水下机器人在外部干扰影响下的航向跟踪控制性能,设计一种基于非线性干扰观测器的滑模控制器.有条件地简化欠驱动自治水下机器人的水平面模型,建立简化模型的状态方程;构造非线性干扰观测器,设计基于干扰观测器的滑模控制器,根据Lyapunov稳定性理论确保闭环系统的稳定性.仿真结果表明:存在外界干扰的情况下,基...     

基于变波阻抗控制策略的六足机器人双边遥操作

针对变时延条件下六足机器人行进任务中的跟踪性较差问题,本文提出了一种基于波阻抗在线补偿策略的六足机器人 双边遥操作控制方法。 该策略以四通道控制架构为基础,采用时延预估器对通信时延进行预估,并设计波阻抗在线调整规则, 以此提高系统的跟踪性。 同时结合时域无源性控制方法,对通信环节与环境端潜在的有源性进行二次补偿,保证系统的绝对无 源,利用 Llewellyn 准则设计主从端的控制律参数。 搭建基于 Vortex 半物理仿真实验平台与实物实验平台对本文所提出的方法 进行验证。 实验结果表明变波阻抗控制结合时域无源性控制可以保证系统的无源性,相对于传统双边遥操作速度跟踪性提高 了 84. 3% ,力波动范围降低了 84. 7% 。     

一种永磁同步风机全速范围内平稳控制策略

目前,永磁同步电机无感控制通常采用观测器结合开环启动的方法。针对启动过程中开闭环状态切换设计了一种新的过渡函数以提高过渡阶段的稳定性;同时设计了一种结合增强型锁环和复系数滤波器的滑模观测器,提高了转子转速的求解精度。最后,通过Simulink仿真和实验,验证了该方法可以实现电机全速范围的平稳控制。     

遥操作在设备维修中的应用

针对远程设备维修遥操作系统时延对可操作性、稳定性和安全性的影响进行了探讨。提出基于增强现实技术构建本地操作系统，将具有时延的远程通讯排除在本地控制循环外，同时采用友好的人机交互手段提高系统的可操作性；采用预测显示控制远程维修机器人的控制方式，保证系统的操作稳定性和安全性。构建了维修实验平台，验证了方法的可行性和有效性。     

Stabilization of multi-input hybrid fractional-order systems with state delay

In this paper, the stabilization of a particular class of multi-input linear systems of fractional order differential inclusions with state delay using variable structure control is considered. First, the sliding surface with a fractional order integral formula is defined, and then the sufficient conditions for stability of the sliding surface are derived. Also, the concepts related to sliding control stabilization of differential inclusion systems with integer order are extended to differential inclusion systems with fractional order 0<q<1. Furthermore, for stabilization of fractional order systems with delay in the state space, a feedback and the concept of the norm of a state space is exploited. Finally, simulation results are provided to show the effectiveness of the proposed method.     

Application of full order sliding mode control based on different areas power system with load frequency control

In the traditional sliding mode control method, there always exist the singularity due to the reduced order of the control method. In order to eliminate the singularity, I propose a new full order sliding mode control method in this article, which has been firstly applied to load frequency control. The full order sliding mode control method includes the terminal sliding mode control (TSM) and the linear sliding mode control (LSM). TSM has the good characteristic of eliminating the singularity due to the avoidance of derivative of terms with fractional power factors. While the LSM is easy to design and has fast time convergence comparing to TSM. The model is based on the system with different kinds of turbine or the same kind of turbine, which contains the nonlinearities. The control purpose is to adjust the frequency deviation to zero. Through the simulation results, it is shown that the frequency deviation can be kept to zero in the condition of different load disturbances by the two approaches, which approves the robustness of the proposed methods. In addition, we compare the two methods with the traditional sliding mode control (SMC), which proves the superiority of the two methods in terms of chattering and response time.     

基于干扰观测器的时滞非线性切换系统滑模控制方法

为实现更加精准的时滞非线性切换系统滑模控制,应用干扰观测器设计一种新的系统滑模控制方法。构建时滞非线性切换系统模型,针对系统在发生结构变化时会产生复合干扰变化的情况,设计了一种非线性切换干扰观测器,实施系统不连续干扰的估计。通过 Backstepping 方法结合干扰观测器,设计一种切换滑模控制器,依据标量非线性特性打造一个滑模面,通过滑模控制器算法使时滞非线性切换系统能够满足滑模面的实际可达性条件,完成切换滑模控制器设计,实现系统的滑模控制。对设计的滑模控制方法进行测试,实验中选择的时滞非线性切换系统为一种变后掠翼 NSV 。实验结果表明,该设计方法能够实现较为准确地切入信号跟踪,表现出了很好的切换复合干扰估计性能。     

基于模糊切换增益调节的惯性稳定平台滑模控制

为了实现航空遥感惯性稳定平台在复杂多源扰动环境下的高精度控制,提出基于模糊滑模的惯性稳定平台高精度控制 方法,通过对总和扰动抑制实现对多源扰动抑制,从而提高稳定平台控制精度。 首先将惯性稳定平台的所有扰动视为整体,基 于滑模等效控制设计惯性稳定平台的全局快速终端滑模控制器,实现系统状态快速、精确地收敛到平衡状态并且不离开滑模 面。 其次,针对控制系统存在鲁棒性与抖振问题无法兼顾的问题,在滑模控制基础上融合模糊切换增益调节,设计模糊规则对 惯性稳定平台滑模控制中的切换增益进行实时调节,从而利用切换增益消除干扰项。 最后,对所提出方法的正确性进行仿真以 及实验验证。 结果表明,基于模糊切换增益调节的滑模控制方法扰动抑制能力强、稳定精度高,相对于 PID 控制和全局快速终 端滑模控制,稳定精度分别提高 32. 7% 和 15. 3% 。     

Composite fuzzy sliding mode control of nonlinear singularly perturbed systems

This paper deals with the robust asymptotic stabilization for a class of nonlinear singularly perturbed systems using the fuzzy sliding mode control technique. In the proposed approach the original system is decomposed into two subsystems as slow and fast models by the singularly perturbed method. The composite fuzzy sliding mode controller is designed for stabilizing the full order system by combining separately designed slow and fast fuzzy sliding mode controllers. The two-time scale design approach minimizes the effect of boundary layer system on the full order system. A stability analysis allows us to provide sufficient conditions for the asymptotic stability of the full order closed-loop system. The simulation results show improved system performance of the proposed controller as compared to existing methods. The experimentation results validate the effectiveness of the proposed controller.     

A new fractional-order sliding mode controller via a nonlinear disturbance observer for a class of dynamical systems with mismatched disturbances

This paper investigates the stabilization and disturbance rejection for a class of fractional-order nonlinear dynamical systems with mismatched disturbances. To fulfill this purpose a new fractional-order sliding mode control (FOSMC) based on a nonlinear disturbance observer is proposed. In order to design the suitable fractional-order sliding mode controller, a proper switching surface is introduced. Afterward, by using the sliding mode theory and Lyapunov stability theory, a robust fractional-order control law via a nonlinear disturbance observer is proposed to assure the existence of the sliding motion in finite time. The proposed fractional-order sliding mode controller exposes better control performance, ensures fast and robust stability of the closed-loop system, eliminates the disturbances and diminishes the chattering problem. Finally, the effectiveness of the proposed fractional-order controller is depicted via numerical simulation results of practical example and is compared with some other controllers.     

树障清理空中机器人的姿态控制器设计

以一种用于对高压线路附近的树障进行清理的树障清理空中机器人为研究对象,分析其姿态控制问题。首先,建立了具有新型结构的树障清理空中机器人的姿态动力学模型和控制分配矩阵。然后,为了克服惯性矩阵的不确定性,采用滑模方法设计姿态控制器;同时,引入非线性函数来改进传统的边界层法以提高控制器性能;接着提出了一种切换控制分配矩阵的方法来解决空中机器人在切割作业过程中的动力学模型变化的问题。最后,在仿真平台上实现了上述控制器。实验结果表明,本滑模控制器具有良好的姿态控制性能,能有效克服机体惯量的不确定性;通过切换控制分配矩阵实现了空中机器人在切割作业过程中的姿态稳定。     

Some long time delay sliding mode control approaches

This paper presents a combined approach of predictive structures with sliding mode control (SMC). Control schemes have been proposed looking for performance and robustness improvement. These structures were designed for processes that can be approximated either by a first order plus time delay or an integral first order plus time delay model broadly used on chemical processes. The proposed schemes were tested for performance and robustness against set point changes and disturbances as compared with classical approaches.     

气动机械手轨迹的Terminal滑模控制方法

应用Terminal滑模控制方法对三轴直角坐标型气动机械手进行连续轨迹控制。首先建立了气动位置伺服系统的数学模型,然后运用Terminal滑模控制对机械手进行轨迹控制。仿真研究结果表明,采用高阶非线性的Terminal滑模控制方法,可以使该机械手对空间直线轨迹的跟踪误差只在未达到收敛点的时间段内较大,在到达收敛点后能完全跟踪目标轨迹。     

Nonlinear adaptive control based on fuzzy sliding mode technique and fuzzy-based compensator

It is difficult to efficiently control nonlinear systems in the presence of uncertainty and disturbance (UAD). One of the main reasons derives from the negative impact of the unknown features of UAD as well as the response delay of the control system on the accuracy rate in the real time of the control signal. In order to deal with this, we propose a new controller named CO-FSMC for a class of nonlinear control systems subjected to UAD, which is constituted of a fuzzy sliding mode controller (FSMC) and a fuzzy-based compensator (CO). Firstly, the FSMC and CO are designed independently, and then an adaptive fuzzy structure is discovered to combine them. Solutions for avoiding the singular cases of the fuzzy-based function approximation and reducing the calculating cost are proposed. Based on the solutions, fuzzy sliding mode technique, lumped disturbance observer and Lyapunov stability analysis, a closed-loop adaptive control law is formulated. Simulations along with a real application based on a semi-active train-car suspension are performed to fully evaluate the method. The obtained results reflected that vibration of the chassis mass is insensitive to UAD. Compared with the other fuzzy sliding mode control strategies, the CO-FSMC can provide the best control ability to reduce unwanted vibrations.