一类欧-拉系统的全系数自适应控制研究

对于动力学方程未知的全驱动多变量欧-拉系统,进行了基于特征模型的全系数自适应控制方法研究.根据全系数自适应控制思想,针对全驱动欧-拉系统提出了差分方程形式的特征模型,并得到该特征模型各系数的一些性质.基于建立的特征模型,提出多变量黄金分割控制律和相应的自适应控制策略,并对闭环系统的稳定性进行了分析.最后对两连杆的空间机器人进行了仿真,仿真结果表明了该自适应控制方法的优越性.     

一类非线性时变系统的全系数自适应控制方法

文中针对一类连续时间非线性时变系统的采样自适应控制问题,给出了一种离散化建模方法,推导得到了相应的离散化模型的系数表达式及变化规律,在此基础上设计了基于该离散化模型的全系数自适应控制方法并给出了保证闭环系统有界稳定的充分条件.数学仿真结果表明文中提出的自适应控制方法可以取得满意的控制性能.最后,对一类高阶非线性时变系统采用低阶全系数自适应控制方法的可行性和条件进行了初步的探讨.     

偏差补偿稀疏自适应滤波算法

为解决输入信号受到噪声干扰和系统发生时变导致ZA-LMS算法估计精度下降的问题,提出一种偏差补偿稀疏自适应滤波算法.算法是在LMS算法的代价函数中添加了l1范数,并导出新的滤波器权系数更新公式,使该算法获得一个指向零矢量的修正量.将无偏准则应用于算法的自适应迭代公式,推导出的偏差补偿项,用以修正输入噪声带来的偏差.仿真...     

卫星天线跟踪指向控制系统的全系数自适应控制

本文根据全系数自动适应控制的原理，进行了卫星天线跟踪指向控制系统的设计和数学仿真研究，论文尝试将单变量全系数自适应控制向多变量全系数自适应控制进行推广，并在多变量系统中取得了满意的解耦控制效果，最后，进一步探讨了所设计的控制器在工程应用中可能产生的问题，并给出了满意工程要求的卫星天线跟踪指向控制系统数学仿真结果。     

黄金分割在自适应鲁棒控制器设计中的应用

本文基于全系数自适应控制理论[1],介绍黄金分割自适应鲁棒控制器的设计方法及其实 际应用,并从理论上证明了:在采样周期满足一定条件下,对于参数未知、线性定常或慢变的 二阶对象,黄金分割自适应控制器可以保证控制系统在起动过程中的稳定性和良好的过渡特 性.从而为二阶系统在初始过渡过程阶段实现自适应控制提供了理论依据.本文最后给出了 仿真研究结果.     

Research on Fuzzy Self Adaptive PID Controller with Parameters Tuning

主要研究了模糊自适应PID控制器参数整定方法,给出了预估计PID参数值的经验公式和方法.用MATLAB软件对PID控制、模糊自适应PID控制的控制性能分别进行了仿真研究,结果表明参数模糊自整定PID控制具有良好的稳态精度和自适应能力.     

杂波协方差矩阵结构的融合估计方法

针对特定杂波背景下的最优或次优杂波协方差矩阵估计方法难以适应过渡杂波环境的问题,提出协方差矩阵结构的融合估计方法,通过调整参数涵盖现有的3种杂波协方差矩阵估计方法,并分析所提出方法对应的自适应归一化匹配滤波器的自适应特性.其次,确定了控制参数的经验公式,经验公式符合数值结果.最后,从估计精度、恒虚警率特性和检测性能3个方面对所提出方法和已有方法进行对比分析.仿真结果表明,在过渡杂波环境中,所提出方法的精度更高、检测效果更好,对实际杂波非高斯程度时空渐变性具有较强的适应能力.     

液压釜温度自适应预测控制

详细介绍了液压釜温度系统自适应控制方案、误差分析及实际应用调试情况.应用 全系数自适应控制理论及模型预测控制原理设计了一种新的自适应预测控制方案,并给出了 控制算法的稳定性证明及闭环系统稳态误差和动态特性分析.实际应用表明,该方法对建模 误差、系统延时及测量噪声具有较好的鲁棒性.     

用Gauss—Markov估计求自适应波束形成器的加权系数

本文用Gauss-Markov估计方法,求得波束形成器的加权系数,为了自适应算法的需要,给出了计算加权系数的递推公式,并用仿真结果验证了递推公式的收敛性     

小波变换域图像水印嵌入对策和算法

稳健性是图像隐形水印最基本的要求之一.嵌入对策、嵌入公式、嵌入强度都影响水印的稳健性.提出了一个基于离散小波变换(DWT)的新的隐形水印嵌入对策.根据小波图像系数的分布特点和对小波系数振幅的定性、定量分析,水印应当首先嵌入小波图像低频系数,若有剩余,再按小波图像频带重要性的排序嵌入高频带.同时指出,水印嵌入到小波图像低频系数和高频系数需要用不同的嵌入公式.应用该嵌入对策,提出了一种把视觉系统掩蔽特性结合到水印编码过程中的自适应水印算法:将小波系数组织成小波块,采用一种新的方法将小波块分类,并根据分类的结果     

一种温度控制系统

本文介绍一种用STD总线16位工业控制机和C语言实现的温度控制系统.作者构造 了具有时滞的一阶和二阶被控对象,用全系数自适应控制和模糊控制等方法实现温度实时控 制,其鲁棒性明显优于PID调节器.     

An all-coefficient adaptive control method for a class of nonlinear time-varying systems

In this paper, the extension of the all-coefficient adaptive control method to nonlinear time-varying systems is studied. A novel discretizing method is first proposed to derive the discrete-time model for a class of nonlinear time-varying systems. The characteristics of the coefficients of the discrete-time model are derived by this method, based on which the all-coefficient adaptive control method is given for the class of nonlinear time-varying systems. Sufficient conditions on the closed-loop stability ...     

液压釜温度自适应预测控制1)

This paper introduces the details of the adaptive control scheme,error analysis and field adjustment of a hydraulic cauldron control system.A kind of new adaptive predictive control scheme is designed based on the all-coefficient adaptive control theory and model predictive control theory.The stability of this control algorithm is proved,and the analysis of error in stable stage and analysis of dynamic performance in the closed loop system are given.The actual application shows that the method proposed in this paper has good robustness to model error,system delay and measure noise.     

基于特征模型自适应方法的一类最小相位非线性系统稳定性分析

在特征建模理论中,由全系数自适应控制器组成的闭环系统是一个非常复杂的混合系统,采用传统自适应框架难以进行分析,因此,稳定性分析一直是该领域的一个难点.本文以一类最小相位、相对阶为2的单输入单输出(SISO)高阶非线性系统为例,通过一种新的特征建模方法,把高阶混合系统变换为一个含有稳定未建模误差的、参数有界慢时变的采样间接自适应控制问题,并利用基于欧拉近似离散化模型的采样系统稳定性分析方法进行了系统分析.该方法可进一步推广到任意相对阶的SISO或多输入多输出(MIMO)系统甚至无限维最小相位系统中去.     

Characteristic model-based all-coefficient adaptive control for automatic train control systems

Safe and reliable automatic train control is a primary consideration for any advanced rail transit system. This paper introduces the characteristic model-based modeling method into ATC system and develops an all-coefficient adaptive control. Two characteristic models,namely speed characteristic model and position characteristic model,are established for analyzing both train traction and cruising dynamical characteristics.Control strategies are proposed using single speed feedback and speed/position bi-feedback. Numerical simulations are carried out to verify the effectiveness of the proposed strategies,showing that control objective and required dynamic performance are well satisfied. Moreover,the system shows robustness against time-varying model uncertainties and unknown operational environment dynamics.     

Control of a flexible rotor active magnetic bearing test rig: a characteristic model based all-coefficient adaptive control approach

Active magnetic bearings(AMBs) have found a wide range of applications in high-speed rotating machinery industry.The instability and nonlinearity of AMBs make controller designs difficult, and when AMBs are coupled with a flexible rotor, the resulting complex dynamics make the problems of stabilization and disturbance rejection, which are critical for a stable and smooth operation of the rotor AMB system, even more difficult. Proportional-integral-derivative(PID) control dominates the current AMB applications in the field. Even though PID controllers are easy to implement, there are critical performance limitations associated with them that prevent the more advanced applications of AMBs, which usually require stronger robustness and performance offered by modern control methods such as H-infinity control and μ-synthesis. However, these advanced control designs rely heavily on the relatively accurate plant models and uncertainty characterizations, which are sometimes difficult to obtain. In this paper, we explore and report on the use of the characteristic model based all-coefficient adaptive control method to stabilize a flexible rotor AMB test rig. In spite of the simple structure of such a characteristic model based all-coefficient adaptive controller,both simulation and experimental results show its strong performance.     

Leader-follower formation control without leader’s velocity information

In this paper,we consider the mobile robots formation control problem without direct measurement of the leader robot’s linear velocity.Two decentralized nonlinear algorithms are proposed,respectively,based on adaptive dynamic feedback and immersioninvariance estimation based second order sliding mode control methodologies.The main idea is to solve formation problem by estimating the leader robots’s linear velocity,while maintaining the given predefined separation distance and bearing angle between the leader robot and the follower robot.The stability of the closed-loop system is proven by means of the Lyapunov method.The proposed controllers are smooth,continuous and robust against unknown bounded uncertainties such as sensor inaccuracy between the outputs of sensors and the true values in collision free environments.Simulation examples and physical vehicles experiments are presented to verify the effectiveness of the proposed design approaches,and the proposed designed methodologies are carefully compared to illustrate the pros and cons of the approaches.     

自适应模糊PID算法在高能激光武器液压管道监控系统中的应用

针对高能激光武器在发射强激光束时在其液压管道中会产生大量的热量,提出了基于自适应模糊PID算法的控制器。该控制器不但可以对单一的控制对象根据模糊经验公式在线修正相应的PID参数,而且还可以有效地应对该液压管道中模型不确定性,时变性,滞后性等特性。系统由工业控制计算机,数据采集仪和各类传感器等构成,将温度作为主控参数,采用自适应模糊PID控制算法实现了对液压管道的温度、流量和压强的实时监控,通过实验取得了良好的控制效果。