输入受限不确定离散系统的灰色滑模控制

对于输入受限离散系统,首先构造出输入受限条件的等效约束矩阵,然后基于线性矩阵不等式给出了满足输入受限条件的切换函数时变参数的构造方法.采用离散趋近控制,结合李雅普诺夫函数和线性矩阵不等式方法提出了滑动模态渐近稳定的充分条件,对不确定部分建立灰色估计模型,证明了闭环系统的稳定性.理论和仿真表明,不仅利用到基于等效控制的滑模控制器构造简单、易于实现等优点,而且满足输入受限条件,克服了传统基于等效控制的滑模控制器瞬时输出量过大的缺点,有效地消除了系统抖振和不确定因素的影响.     

基于观测器的网络化多智能体预测控制

研究含模型不确定性的刚性航天器输入受限时的姿态跟踪控制设计问题.针对修改的罗德里格斯姿态参数描述的航天器姿态跟踪动力学模型,基于一种有界非线性连续函数和修改的罗德里格斯姿态参数自身有界性,设计鲁棒自适应状态反馈受限控制器,不确定参数的自适应更新律可保证在线估计参数的有界性.通过所提出的输入受限控制设计方法给出输入受限幅值、期望轨迹上界、模型不确定性上界与控制器增益之间的定量关系,并采用李亚普诺夫方法证明通过选择合适的控制器参数可以保证闭环系统角速度误差渐近收敛到零,且姿态跟踪误差收敛到原点小邻域,同时保证控制量始终在预先给定的受限范围内.仿真结果验证了所设计的控制器可在输入受限的情况下完成控制目标并有效抑制模型的不确定性影响.     

受限指令预设性能自适应反演控制器设计

针对一类含参数不确定性的输入和状态受限的非线性系统,提出一种受限指令预设性能自适应反演控制器设计方法.采用自适应反演方法,同时考虑输入和状态受限构建受限指令滤波器,以解决“计算膨胀”的问题;引入伪控制减缓方法对误差进行补偿;最后考虑了补偿跟踪误差的瞬态性能.通过Lyapunov理论对所设计的控制器进行稳定性分析,并通过仿真实例验证了所提出方法的正确性和有效性.     

基于全状态预设性能的受限指令反演控制器设计

针对输出预设性能较多的研究现状,基于一类输入和状态受限的非线性系统,重点分析全状态预设性能,提出一种基于全状态预设性能的受限指令反演控制器设计方法.采用自适应反演方法,构建受限指令滤波器,解决“计算膨胀”的问题;为补偿输入和状态误差,引入伪控制减缓方法;最后分析全状态预设性能,对系统瞬态性能进行重点分析.采用Lyapunov理论对控制器进行稳定性分析,仿真实例表明了所提出方法的正确性和有效性.     

一类状态/输入受限的不确定非仿射非线性系统 鲁棒自适应backstepping控制

针对一类状态/输入受限的不确定严格反馈非仿射非线性系统跟踪控制问题,提出一种鲁棒自适应backstepping控制策略.在保证系统精度的前提下,对状态/输入受限的非仿射系统进行Taylor级数在线展开,得到其仿射形式;为保证系统复合扰动在线准确逼近,提出基于投影算子的递归扰动模糊神经网络干扰观测器(RPFNNDO);在考虑不确定系统存在状态受限和输入饱和等因素下,结合障碍Lyapunov函数、tanh函数及Nussbaum函数,利用backstepping方法设计控制器,并采用Lyapunov稳定理论分析闭环系统稳定性.应用于无人机航迹控制的仿真结果验证了所提方法的有效性.     

基于状态观测器的双模控制方法

对于状态不可测的输入受限线性时不变系统,提出一种基于状态观测器的控制方法. 该方法采用双模控制策略,将不变椭圆集概念同时应用于观测器的状态方程和误差方程,给出 估计状态不变性和控制输入可行性条件并给出了闭环系统的稳定性定理.仿真结果表明了所提 方法的有效性.     

状态和输入受限的切换奇异布尔控制网络的最优控制

本文研究了状态和输入均受限的切换奇异布尔控制网络的最优控制问题.利用矩阵半张量积方法获得受限切换奇异布尔控制网络的等价代数形式.然后通过类似针变化得到了存在最优控制的必要条件,并且提出了一个算法设计切换序列和控制策略使收益函数最大化.最后给出例子验证所得结果的有效性.     

一类控制输入饱和受限的不确定系统滑模控制

本文研究控制输入饱和受限情况下不确定系统的滑模控制问题,其中,被控对象同时存在状态矩阵不确定性和控制增益矩阵不确定性.设计了一种积分型切换面和一个具有特殊结构的滑模控制律,可以在参数不确定和控制受限影响下保证系统状态轨迹有限时间内到达指定的切换面,利用等价控制律方法给出了滑模动态渐近稳定的充分条件.数值仿真例子验证了本文算法的有效性.     

输入受限下的无人机编队控制方法研究

针对多旋翼飞行器在轨迹跟踪过程中控制输入受限的问题，设计了一种控制输入受限下的四旋翼无人机协同编队分布式控制算法。首先，对于外环位置子系统，基于线性矩阵不等式的方法，设计了输入受限下的多旋翼飞行器的编队控制律，使得所有无人机的位置收敛到所需的编队模式。其次，对于内环姿态子系统，采用基于双曲正切的方法设计控制输入受限的控制律，使多无人机的姿态趋于一致。最后，基于Lyapunov稳定性理论，证明了系统的稳定性，仿真结果表明，所设计的控制器能够达到良好的协同跟踪控制效果。     

状态和输入受限的切换奇异布尔控制网络的最优控制（英文）

本文研究了状态和输入均受限的切换奇异布尔控制网络的最优控制问题.利用矩阵半张量积方法获得受限切换奇异布尔控制网络的等价代数形式.然后通过类似针变化得到了存在最优控制的必要条件,并且提出了一个算法设计切换序列和控制策略使收益函数最大化.最后给出例子验证所得结果的有效性.     

Stabilising feedback control schemes of dynamical systems with completely unknown saturated inputs: an adaptive design method

The objective of this paper is mainly to present a simple design method to synthesise the stabilising feedback control schemes for dynamical systems with input saturations. In this paper, such a simple design method, called an adaptive design method, is presented so that (i) the presented design method is easy to understand for the system designers; (ii) it is not necessary to know any information on the saturated input nonlinearities; and (iii) the resulting control schemes are simple and easy to implement in practical control problems. Here, a linear dynamical system with any unknown saturated input nonlinearities is used to describe this method. For such dynamical systems, by making use of the presented design method, the resulting feedback control schemes consist of a conventional optimal control law and an adaptive control gain, and the resulting closed-loop control dynamical systems are globally stable. By combining the presented adaptive design method with other control ones, a number of interesting results can be expected for a rather large class of dynamical systems with saturation in the actuators. Finally, some illustrative numerical examples are provided to demonstrate the validity of the presented adaptive design method.     

医学影像学诊断报告书智能化书写方法研究

针对医学诊断报告书编辑效率低问题,本文提出了一种诊断报告书智能交互书写方法。该方法将报告内容分为既有文本、输入文本、单选文本和多选组合文本四种文本类型,利用XML语言来描述由四种文本类型生成的报告书模板,分别采用编辑框、单选框和复选框窗体控件界面,实现文档内容的智能交互书写,最后将报告内容用XML格式保存。实验表明,该方法缩短了诊断报告书的书写时间,为医学影像学诊断报告书快速书写提供了新的方法。     

多变量系统模糊解耦自适应控制

对象模型难以确定的系统，采用经典控制方法难以实现解耦控制，作者应用模糊控制理论，研究了一种无需对象模型的模糊解耦自适应控制方法。本文介绍了这一方法，导出实现模糊解耦自适应控制的充要条件，并给出了仿真结果。     

Integral Sliding Mode Fault‐Tolerant Control for Spacecraft With Uncertainties and Saturation

An integral sliding mode fault‐tolerant control method is proposed to deal with faults with matched uncertainties, unmatched uncertainties, and input saturation. Integral sliding mode, control allocation, and parameter identification are included in this method. The Lyapunov stability conditions of the integral sliding mode control for uncertainties and input saturation, respectively, are obtained, which denote the robustness extent of the controller. The direct method for control allocation is improved by adding a judgement before calculating for each facet. Finally, the fault‐tolerant scheme is applied to a six‐wheel spacecraft and simulations are given to show its effectiveness.     

Adaptive Sliding-Mode Control of an Automotive Electronic Throttle in the Presence of Input Saturation Constraint

In modern vehicles, electronic throttle (ET) has been widely utilized to control the airflow into gasoline engine. To solve the control difficulties with an ET, such as strong nonlinearity, unknown model parameters and input saturation constraints, an adaptive sliding-mode tracking control strategy for an ET is presented. Compared with the existing control strategies for an ET, input saturation constraints and parameter uncertainties are adequately considered in the proposed control strategy. At first, the nonlinear dynamic model for control of an ET is described. According to the dynamical model, the nonlinear adaptive sliding-mode tracking control method is presented, where parameter adaptive laws and auxiliary design system are employed. Parameter adaptive law is given to estimate the unknown parameter with an ET. An auxiliary system is designed, and its state is utilized in the tracking control method to handle the input saturation. Stability proof and analysis of the adaptive sliding-mode control method is performed by using Lyapunov stability theory. Finally, the reliability and feasibility of the proposed control strategy are evaluated by computer simulation. Simulation research shows that the proposed sliding-mode control strategy can provide good control performance for an ET.      

Chaos control and synchronization via a novel chatter free sliding mode control strategy

In this paper, we propose a novel chatter free sliding mode control (SMC) strategy for chaos control and synchronization to the nonlinear uncertain chaotic systems. A new sort of dynamical sliding mode surface with both integral and differential operators is introduced to divert the discontinuous sign function switch term into the first derivative of the control input; hence a chatter free control input is obtained for the chaotic systems with uncertainties. Based on the Lyapunov stability theory and SMC technique, stability analysis is performed and a theorem serving as designing the chatter free sliding mode control input is also proposed. In the simulation part, first, the results regarding chaos control and synchronization are given to show that the proposed strategy can control the states of the uncertain chaotic systems to desired states with fast speed. In order to show the advantage of eliminating chatter in control input of our method, we give the simulation results performed by traditional SMC and the method proposed recently. Simulation results indicate that this novel chatter free sliding mode control strategy is very effective to chaos control and synchronization.     

A memristor-based architecture combining memory and image processing

Image processing is a type of memory-access-intensive application and is applied in many fields.Logic operations are very simple ones in image processing.During these operations,memory access takes a majority of the total time consumed,which puts a great pressure on memory access speed and bandwidth.However,in traditional von Neumann architecture,memory access is the inherent bottleneck of the system;that is,the speed of memory’s data supply is far lower than the data request of processor.Memristor is considered to be the fourth circuit element after resistor,capacitor and inductor.It has the capacity of both processing and memory,which supplies a new idea for solving the"memory wall"problem.In this paper,memristor is used to build an architecture combining computing and memory,where the memory has the ability to handle some simple image processing operations.This architecture can reduce readings and writings of memory effectively,which saves memory bandwidth thus improving the efficiency of the system.Logic operations of images are considered in this paper to validate the architecture.The experimental results and theoretical analysis indicate that the architecture can reduce memory access effectively.     

Control input separation by actuation mode expansion for flow control problems

A control input separation method is proposed for reduced-order modelling in boundary control problems. The dynamics of flow systems are typically described by partial differential equations where the input affects the system through boundary conditions. From a control design perspective it is most desirable and natural to employ finite-dimensional representations in which the input enters the dynamics directly. The method proposed here to resolve the input from the boundary conditions is based on obtaining a proper orthogonal decomposition of the unforced flow of the system, and then augmenting this decomposition by optimally computed actuation modes, built using snapshots of the actuated flow. A reduced-order Galerkin model is then derived for this expansion, in which the input appears as an explicit term in the system dynamics. The model reduces exactly to the original baseline case under zero input conditions. The proposed method is then compared to an existing input separation technique, namely the sub-domain separation method. A boundary control example regarding the 2D incompressible Navier–Stokes equation is considered to illustrate the proposed method, where a controller is designed to achieve tracking of a desired 2D spatial profile for the flow velocity.     

Design of Integral Sliding Mode Control Using Decoupled Disturbance Compensator with Mismatched Disturbances

This paper deals the problem of integral sliding mode control using decoupled disturbance compensator for discrete-time systems with mismatched disturbances. The proposed method allows the disturbance compensation to be modified separately from the control input, since the two inputs of system are completely decoupled. In the developed method, the actual disturbance is estimated by the decoupled disturbance compensator (DDC) method to design the control input and stabilize the system. Integral sliding mode control with DDC scheme minimizes the control effort and improves the system performance. Main advantage of this method is to eliminate the reaching phase and reduce the control effort, simultaneously. Finally, simulation results are shown to demonstrate the usefulness of the presented methodology.

     

Vega中基于DirectInput的USB操纵杆的控制研究

Vega只提供对操纵杆的串行端口支持,而当前主流操纵杆采用USB端口,分析了Vega中输入设备和运动模式的管理方式,提出了一种基于DirectInput的USB操纵杆的控制方法,并以北通方向盘为例,实现了USB口方向盘与Vega中简单运动模式和自定义运动模式的绑定,实验结果表明,该方法很好解决了Vega与USB口输入设备驱动的兼容性问题,且响应速度快,获取数据效率高.