框架结构半主动控制优化设计

以框架结构为研究对象,在设计出作动器的前提下,对结构设计参数进行摄动,以控制效果为优化目标来确定最优设计参数。在模型降阶方面,选择了基于系统内平衡理论的降阶方法。考虑到磁流变阻尼器的非线性特点及结构设计参数发生摄动时系统的可控性,研究了控制力为阶跃函数和具有较大的增益裕度的广义预测控制,并提出了相应的半主动控制方法,最后给出了计算实例。     

车辆半主动悬架技术的发展现状

本文主要介绍了车辆半主动悬架技术产生的背景、半主动悬架执行机构—可调阻尼减振器的发展现状和最优控制、自适应控制、模糊控制等半主动悬架控制策略,并指出性能价格比和可靠性是车辆半主动悬架技术商品化、产业化的关键。     

磁流变阻尼器连接相邻建筑物的工作原理

在过去发生的大型地震中,相邻高层建筑结构之间相互碰撞导致了建筑物的严重破坏。国内外研究人员测试了用于连接相邻建筑物的不同地震控制装置的减震效果。磁流变减压器对于相邻建筑物在多种频率范围内的减震效果都十分有效。本文总结了国内外研究现状及在实际工程应用中磁流变阻尼器的优点,最后概述磁流变阻尼器连接的两相邻建筑物的工作原理。     

基于Abaqus的悬架空气弹簧静态力学特性研究

以某商用车悬架用空气弹簧为研究对象,应用非线性有限元分析软件Abaqus建立了空气弹簧的有限元分析模型,对其垂向静态力学特性进行了计算分析,并与悬架空气弹簧垂向静态力学特性台架试验结果进行对比.结果表明,仿真计算结果与试验结果吻合度较好,证明数值仿真方法可用于悬架空气弹簧设计开发.     

一种爆胎车辆的悬架半主动控制方法

S本发明公开了一种爆胎车辆的悬架半主动控制方法,属于车辆底盘悬架控制领域。通过胎压传感器、轮胎加速度传感器、激光测距传感器、车速传感器及车身加速度传感器将采集数据实时传入ECU电子控制单元;ECU根据各轮胎气压变化情况判断轮胎是否爆胎并确定具体的爆胎轮位置,同时将正常行驶半主动悬架控制策略切换为爆胎控制策略。本发明充分利用车辆底盘结构组成资源,改善车辆爆胎后各轮胎垂直载荷分配,提高爆胎时的车辆操纵稳定性。     

基于LQR的磁流变阻尼器半主动控制

目前结构半主动控制多以结构位移和速度作为状态反馈从而得到结构的最优控制力。但是考虑到结构的绝对位移测量不便和累积误差,本文研究了基于加速度反馈的线性二次高斯(LQG)算法,用测量简单、可靠的加速度作为反馈量,通过Kalman滤波器估计结构位移和速度,从而对结构进行半主动控制。数值算例分析结果表明,此控制算法能够有效地减小结构的地震反应。     

汽车悬架支架的结构分析及仿真

针对某种卡车悬架支架的载荷作用情况,从静态和动态两方面进行分析处理,评估其力学性能和安全性能.首先,基于UG软件建立悬架支架的参数化模型,导入Ansys中进行分析,两者的Parasolid核心保证了模型的完整和不失真;其次,基于力学原理和数值分析方法对模型进行静力学和动力学分析及仿真,真实再现了悬架支架的工作环境.研究结果表明,此方法明显节约了时间和减少了工作量(尤其对复杂庞大的零部件的建模分析),同时为整车分析和复杂结构的有限元分析提供了必要的参数和依据.     

双时滞影响下的桥梁减震半主动控制系统研究

迄今为止,桥梁减震装置的发展已较为成熟,但在考虑时间滞后的复杂性上还存在一定局限。本文对连续梁桥和减震系统进行建模分析,利用线性增益矩阵构建出带有双时滞的桥梁结构运动控制方程;探讨桥梁减震半主动控制系统的局部稳定性;并以某座大跨连续梁桥为工程实例,进行半主动控制地震反应的数值仿真分析。结果表明,在一定条件下,双时滞补偿可以取得较好的减震控制效果。     

悬架橡胶元件对汽车NVH性能影响的分析方法

研究悬架橡胶元件对汽车NVH(噪声、振动和声振粗糙度)性能影响的分析方法.借助汽车ADAMS仿真模型,运用正交试验设计和回归分析理论,建立悬架橡胶元件特性与整车NVH性能之间的响应方程式.验证结果证明该响应方程的有效性.基于该方程式,可以根据给定的振动目标值反求橡胶元件的力学特性.     

基于智能控制方法的风力发电系统的变桨距控制器

以对风力发电机系统进行功率控制为目的,提出基于智能控制方法的变桨距控制器的设计。风力发电系统结构复杂,具有非线性、时变的特点,单纯的模糊控制和PID控制都不能取得良好的控制效果。针对这一问题,提出风力发电系统模糊PID双模变桨距控制策略。使用Matlab中的Simulink组件建立系统模型,进行仿真试验。仿真结果表明,使用模糊PID双模控制变桨距控制器的风力发电系统确实具有较好的动态性能、收敛速度和静态误差。     

Damping enhancement of rubber dampers for high speed compact disk players

Rubber dampers are widely used to dissipate vibrations generated in machines and electronic equipments due to the excellent damping capacity of rubber. However, the effectiveness of the rubber damper is often limited because of the dependency of its damping characteristics on temperature and frequency. In this study, the damping and stiffness characteristics of the rubber damper for compact and digital video disk players were enhanced by inserting a solid core into the rubber damper with interference tolerance fit. The damping characteristics of the coreinserted rubber damper were investigated experimentally and numerically with respect to the interference tolerance, core roughness, rubber stiffness and damping and environmental temperature. From the experimental and numerical investigations, it was found that the core was effective both for the damping and stiffness enhancement of the damper. Using the results of the experimental and numerical investigations, the optimum design method for the core-inserted rubber damper was suggested.     

Druckschwingungen durch oszillierende Verdrängerpumpen in Rohrleitungssystemen

Pressure Pulsations Caused by Reciprocating Pumps in Piping Systems. The safe design of piping installations for reciprocating pumps requires proper knowledge about the pump/installation interaction. In many cases critical resonance effects can be avoided by proper piping geometry or improved pump performance with respect to the volumetric efficiency (primary measures). Normally it is necessary to use various secondary dampening methods which can influence the acoustics of the piping system. Several examples of experimental computer simulations of damper action – upstream and downstream – are presented for fluidand gas-filled damper versions. The influence of entry geometry of the dampers is explained, hints on the proper geometry of the entries are given and the effects of various dampers and their influence on the total acoustics are discussed. Special reference is made to the effect of orifices as dissipative and acoustic elements in piping systems. The investigation shows the importance of analyzing of the total system of pump, piping installation and vessels or reactors and the application of computer simulation for piping design.     

模糊PID控制系统设计及MATLAB仿真

在工业生产中,PID控制不适合时变系统,其参数调整也更为复杂。模糊PID控制利用专家经验得出的模糊规则,通过模糊控制器近似推理实时修正PID参数,使控制效果良好。选取双关节机械手为研究对象,利用模糊控制规则确定隶属度函数和推理方法,在Simulink中搭建模型进行仿真分析。实验结果表明,模糊PID控制在各方面均优于PID控制系统。     

Optimisation,design and characterisation of a piezoelectric micro suspension

A piezoelectric micro active suspension device has been developed for the application of active isolation of sensitive electronic devices such as frequency generators or inertial sensors. The developed strategy is based on a classical skyhook active damper but adapted and optimised to allow robust implementation onto an adaptive microelectromechanical systems (MEMS). The micro suspension is a silicon beam structure etched in a silicon on insulator (SOI) wafer and is equipped with a pair of piezoelectric transducers obtained from a lead zirconate titanante thin film sandwiched between pairs of electrodes. High performance transducers allow application of the active isolation strategy and demonstrate the possibility to implement skyhook damping with low-voltage control level.     

Fuzzy Control System for a Meat Drying Process

To obtain a high quality dried product, a precise control of many process parameters is required. In most drying installations it is necessary to control inlet and outlet parameters of a drying agent and material being dried. A control system based on Fuzzy Logic is convenient in controlling drying processes having adequate working regimes. The main objective of this project is to study a control system (fuzzy logic) of drying process of dry cured meat products. In the article the problems appearing during designing and remote (over Wide Area Network) operation of Fuzzy Logic Control System used for meat drying processes are presented. The experimental rig is located at IRTA Monells, Spain, and controlled from Technical University of Lodz, Poland.     

SVPWM在内馈斩波串调系统中的应用研究

将具有谐波小、直流电压利用率高、算法简单、规律性强、易于数字化实现特点的电压空间矢量脉宽调制(SVPWM)技术应用到高效节能的内馈斩波串级调速系统中。首先从三相电压型有源逆变器和SVPWM控制技术的基本原理出发,建立基于SVPWM技术的有源逆变控制结构图,利用SIMULINK动态仿真工具实现了SVPWM控制算法在有源逆变的动态仿真。在此基础上搭建硬件实验平台,通过实验的手段证明了将SVPWM技术应用到内馈串级调速系统中的可行性。     

浮法玻璃熔窑温度的模糊PID控制

引入模糊PID控制器控制浮法玻璃熔窑的温度.通过仿真分析表明,系统的实时性和稳定性都得到了明显提高,同时也可以降低工人的劳动强度.     

Double-command fuzzy control of a nonlinear CSTR

In this research, double-command control of a nonlinear chemical system is addressed. The system is a stirred tank reactor; two flows of liquid with different concentrations enter the system through two valves and another flow exits the tank with a concentration between the two input concentrations. Fuzzy logic was employed to design a model-free double-command controller for this system in the simulation environment. In order to avoid output chattering and frequent change of control command (leading to frequent closing-opening of control valves, in practice) a damper rule is added to the fuzzy control system. A feedforward (steady state) control law is also derived from the nonlinear mathematical model of the system to be added to feedback (fuzzy) controller generating transient control command. The hybrid control system leads to a very smooth change of control input, which suits real applications. The proposed control system offers much lower error integral, control command change and processing time in comparison with neuro-predictive controllers.     

Particle dynamics simulations of a piston-based particle damper

A piston-based particle damper geometry is proposed and investigated using experiments and particle dynamics simulations. In particle damping, energy is dissipated through the inelastic collisions and friction between granular particles. Due to their temperature-independent performance, particle dampers are promising alternatives for use in extreme temperature conditions. Using the appropriate inter-particle force models, the simulations agree well with the experimental results. Using simulations, many parameters are investigated in this work for their effects on the damping performance, including material properties, particle size, device geometry, and excitation level. These results provide new understanding of particle damping and may help in the design of next generation particle dampers.     

仿人智能比例控制器与PID FUZZY控制算法的仿真分析

对于具有二阶惯性加纯滞后的不同对象，分别运用常规ＰＩＤ控制、Ｆｕｚｚｙ控制以及仿人智能控制算法进行仿真研究，并对各种控制算法的控制效果进行分析比较。结果表明：仿人智能控制的调节品质明显优于常规ＰＩＤ及Ｆｕｚｚｙ控制，具有响应速度快、超调小（甚至无超调）、过渡过程时间短、控制精度高、系统适应性强等优点。