电流变液体减振器的研究

本文用电流变仪对BW型电流变液体进行测试,并将其用于筒式车用减振器。通过台架试验研究了激振频率、振幅对电流变液体减振器性能的影响,并就电流变液体减振器要求的流体性能进行探讨。研究结果表明,低频大振幅下,随着电场强度变化电流变液体减振器阻尼力变化显著;应用具有电粘特性的流体作为该电流变液体减振器的工作液更有价值。     

采用电流变技术的汽车减振器

电流变减振器的阻尼力可以通过电信号快速、连续地调节，因此这种减振器及其变型结构可以应用在车辆以及其它多种机械装置中以实现振动控制。本文描述了电流变减振器的典型结构及其对电流变流体性能的要求，研制开发了一种新型结构的减振器及其控制系统并给出了试验结果。     

两种电流变减振器结构酌阻尼力分析与比较

电流变液体减振器是一类重要的电流变液体器件。它的特点就在于可以通过调节电场强度来控制电致阻尼力,达到调节复原和压缩阻尼力的目的。电流变减振器在解决空行程问题上,常采用＂三筒结构＂和＂双筒充气式结构＂。通过对这两种结构的阻尼力特性的分析,推导出其在压缩和复原行程中的阻尼力计算公式,并对两种结构的阻尼力特性和结构特点进行比较。     

电流变流体减振器的研究

本文用电流变仪对ＢＷ型电流变液体进行测试，并将其用于简式车用减振器。通过台架试验研究了激振频率，振幅对电流变液体减振器性能的影响，并就电流变液体减振器要求的流体性能进行了探讨。     

电磁阀控制半主动悬架可调减振器的研制

建立了某越野车7自由度模型,分析了该车辆在直线行驶、加速-制动以及转向工况下悬架阻尼变化对车辆稳定性和乘坐舒适性的影响。研制了电磁阀控制阻尼可调减振器,并进行了减振器示功试验、速度特性台架试验,得出被动减振器及可调减振器的示功图和速度特性曲线。结果表明,该可调减振器的软、硬阻尼力随速度的变化有明显的区别,说明基本达到了阻尼的软、硬可调。     

摩托车减振器外特性的计算机模拟与分析

在对摩托车减振器动力学与运动学振动物理模型分析的基础上，探讨了液压阻尼力、摩擦阻力和空气刚度对液压减振器外特性的影响，利用计算机模拟外特性的变化，并与实测的示功图和速度特性进行了对比分析。     

汽车单筒充气磁流变减振器特性的试验研究

分析了汽车单筒充气磁流变减振器的结构和基于磁流变液Bingham本构关系的阻尼力模型,对用于汽车悬架的国外某单筒充气磁流变减振器阻尼力示功特性、温度特性、活塞磁路磁场特性、磁流变液流变特性进行了试验研究。试验结果表明,磁流变阻尼器具有很强的耗能性和可控性;随控制电流增加,其阻尼力增大,电流达到一定时磁场出现磁饱和状态,阻尼力将趋于稳定;随着工作温度升高,减振器压缩阻尼力增大,拉伸阻尼力下降。     

位移相关减振器的阻尼优化设计

提出了一种简单有效的位移相关减振器开槽段阻尼优化设计方法。利用关键速度点的阻尼力对减振器阻尼曲线进行简化,对减振器开槽段关键速度点处的阻尼力进行仿真优化,获得了理想的减振器开槽段阻尼特性曲线。将减振器在目标车后悬架进行了实车试验,结果表明,该位移相关减振器对目标车的乘坐舒适性有明显改善,验证了阻尼优化设计方法的有效性与实用性。     

基于AMESim浮动活塞式限位减振器建模及仿真分析

在研究浮动活塞限位减振器结构和工作机理的基础上,建立浮动活塞限位减振器的数学模型,利用AMESim平台建立其的等效模型,并进行仿真分析,该减振器的特性曲线表明在接近复原行程终点处产生了附加阻尼力,该附加复原阻尼力起限位缓冲作用。利用减振器示功机对浮动活塞限位减振器进行示功特性试验,将试验结果与仿真结果进行比对,验证了基于AMESim的模型的正确性。     

汽车磁流变减振器设计中值得注意的若干技术问题

汽车磁流变减振器利用磁流变液的流变特性可受外加磁场控制的特性，实现减振器的阻尼系数的可控，从而实现阻尼力的控制，基于磁流变换的磁流变减振器的特性是由多种因素所决定的，如磁流变液、工作模式、磁路结构、导磁材料、线圈和机械结构等。对磁流变液的性能、阻尼通道的设计、磁路中磁芯材料的选用以及磁流变减振器的体积补偿等在磁流变减振器设计中值得注意的一些问题进行了探讨。     

土木工程结构振动控制技术及其应用研究

结合工程实际,介绍了结构振动控制方法,并研究液体质量双调谐阻尼器(TLMD)及杠杆质量减振器(LMD)等新型阻尼减振系统.室内及实桥试验表明:由于兼具调谐质量阻尼器(TMD)与调谐液体阻尼器(TLD)的优点,TLMD便于调谐,减振效果与耐久性更好.理论及室内试验证明:与现有减振措施相比,LMD对桥梁景观的不良影响小,易于安装、养护,且减振效果更好,是一种更适于超长斜拉索振动控制的"广谱"减振器.     

基于流固耦合的汽车双筒式减振器动态特性研究

对双筒阀片充气式液压减振器内部结构进行建模,建立了减振器复原行程阻尼力数学模型,明确了活塞杆直径、复原阀片外半径以及气室充入气体的压强为影响阻尼力的3个关键参数,理论分析了结构参数对复原行程阻尼力的影响。利用动网格技术对减振器复原行程的内部流场进行了三维数值模拟,得到了流固耦合下阀片的运动状态、流场的压力云图和速度矢量图等,详细分析了各结构参数对复原阻尼力的影响,验证了减振器工作状态中的油液流动情况及所提出方法的可操作性。     

Force Control of a Semi-Active Damper

Two strategies are investigated for controlling a semi-active damper to track a prescribed force demand signal: (i) 'open loop' control, using a model of the damping force versus velocity characteristics; and (ii) force feedback (closed loop) control.

The damping characteristics and switching transients of a prototype damper were measured, and used to develop a mathematical model of the dynamics of the damper. The two control strategies were investigated using an idealised (constant velocity) test. Their performance was also simulated and measured under realistic operating conditions using the Hardware-in-the-Loop testing method.

Open loop damper control was generally found to give superior performance to force feedback control, due to its smaller phase lag at high frequencies.     

Force Control of a Semi-Active Damper

SUMMARY

Two strategies are investigated for controlling a semi-active damper to track a prescribed force demand signal: (i) ‘open loop’ control, using a model of the damping force versus velocity characteristics; and (ii) force feedback (closed loop) control.

The damping characteristics and switching transients of a prototype damper were measured, and used to develop a mathematical model of the dynamics of the damper. The two control strategies were investigated using an idealised (constant velocity) test. Their performance was also simulated and measured under realistic operating conditions using the Hardware-in-the-Loop testing method.

Open loop damper control was generally found to give superior performance to force feedback control, due to its smaller phase lag at high frequencies.     

Generalized magnetorheological (MR) damper model and its application in semi-active control of vehicle suspension system

In this paper, analytical characterization of the magneto-rheological (MR) damper is done using a new modified algebraic model. Algebraic model is also more preferable because of its low computational expenses compared to differential Bouc-Wen’s model which is highly computationally demanding. This model along with the obtained model parameters is used as a semi-active suspension device in a quarter car model and the stationary response of the vehicle traversing on a rough road is obtained. The control part consists of two nested controllers. One of them is the system controller which generates the desired damping force and the other is the damper controller which adjusts the voltage level to MR damper so as to track the desired damping force. For the system controller a model reference skyhook Sliding Mode Controller (SMC) is used and for the damper controller a continuous state algorithm is built to determine the input voltage so as to gain the desired damping force. The analytical model is subsequently used in the quarter car vehicle model and the vehicular responses are studied. A simulation study is performed to prove the effectiveness and robustness of the semi-active control approach. Results show that the semi-active controller can achieve compatible performance as that of active suspension controller except for a little deterioration.     

乘用车阀控阻尼可调减振器的产业化应用综述

文章梳理了当前乘用车产业中广泛使用的阀控阻尼可调减振器的种类,分别介绍了各类型的代表产品、应用车型、系统组成、阻尼力特性、硬件结构和工作原理等,并对阀控阻尼可调减振器的升级发展方向做出了展望。     

磁流变减振器极限高低温特性及变温正逆模型

磁流变减振器阻尼力和电流的精确控制是实现半主动悬架的算法、达到整车系统控制目标的必要条件,但由于磁流变液的温度敏感性使得磁流变减振器阻尼力强烈依赖温度变化,带来模型失配和控制效果弱化的问题。基于此进行磁流变减振器在不同电流和速度下的高低温(-40℃～80℃)示功试验研究,揭示磁流变减振器在低温下丧失阻尼特性而表现出刚度特性,在高温下黏滞阻尼退化的特性规律。为了描述磁流变减振器随温度变化的复杂非线性特性,提出一种新的磁流变减振器变温参数化双曲滞回模型,该模型引入温度作为自变量,对磁流变减振器黏滞阻尼、刚度及滞回特性进行准确描述。为了面向实际减振器控制,在此双曲滞回模型的基础上,进一步线性化求逆得到磁流变减振器温度修正的逆模型。该逆模型输入预期阻尼力和减振器压缩速度作为自变量,可以直接给出满足减振器力值约束的控制电流。研究结果表明：相较于未进行温度补偿的逆模型,该逆模型能够平均提升12.79%的电流控制精度以及12.53%的控制力跟踪精度;进行温度修正的模型能够在仿真中还原更真实的磁流变减振器力学特性,逆模型能够给出更精确的控制电流,为充分发挥磁流变减振器的能力、实现车辆的半主动悬架精确控...     

一种用于车辆半主动悬架控制的磁流变阻尼器模型

文中对适用于车辆半主动悬架控制器设计的磁流变阻尼器模型进行研究.首先分析阻尼力与位移、速度以及输入电流之间的关系,并结合现有阻尼器模型的优点,提出一种精确的便于控制的双曲正切磁滞模型.接着,将磁流变阻尼器安装在硬件在环仿真平台上进行试验,利用试验得到的阻尼器动态特性数据,进行阻尼器模型的参数辨识和曲线拟合.最后,将基于拟合参数的模型仿真结果与试验数据进行比较,验证了模型的正确性.     

An Experimental Investigation of Preview Control

There is mounting theoretical evidence to suggest that preview control can be of substantial benefit to a semi-active suspension for random road inputs. In this paper, the benefits of wheel-base preview control are measured experimentally, using a prototype semi-active damper in a half-car 'Hardware-in-the-loop' (HiL) rig with a planar two-axle heavy vehicle model. The benefits of preview control using the prototype semi-active damper are found to be less than theoretically possible, due to the phase lag between the demanded and achieved damping force. It is shown that the performance of the prototype damper can be improved significantly by having a theoretical simulation running ahead of the HiL vehicle. The theoretical simulation is used to predict the demanded damper force for the HiL vehicle, and thereby compensate for the phase lag in the prototype damper.     

An Experimental Investigation of Preview Control

There is mounting theoretical evidence to suggest that preview control can be of substantial benefit to a semi-active suspension for random road inputs. In this paper, the benefits of wheel-base preview control are measured experimentally, using a prototype semi-active damper in a half-car ‘Hardware-in-the-loop’ (HiL) rig with a planar two-axle heavy vehicle model. The benefits of preview control using the prototype semi-active damper are found to be less than theoretically possible, due to the phase lag between the demanded and achieved damping force. It is shown that the performance of the prototype damper can be improved significantly by having a theoretical simulation running ahead of the HiL vehicle. The theoretical simulation is used to predict the demanded damper force for the HiL vehicle, and thereby compensate for the phase lag in the prototype damper.