Design of LQG Controller for Semi-active Suspension Based on Improved Analytic Hierarchy Process

建立了包含半主动悬架的4自由度车辆动力学模型,应用最优控制理论设计了车辆半主动悬架LQG控制器,并在Matlab/Simulink环境下对系统模型进行仿真.以车身垂向加速度、俯仰角加速度、悬架动挠度、轮胎动位移和悬架控制力作为车辆LQG控制的性能评价指标,采用层次分析法和改进层次分析法确定各指标的加权系数.仿真结果表明,与被动悬架相比,采用半主动悬架能有效地提高车辆的乘坐舒适性;而与层次分析法相比,使用改进的层次分析法更易于确定加权系数,更便于设计LQG控制器.     

半主动空气悬架神经网络自适应控制的仿真研究

章提出将神经网络自适应控制策略用于半主动空气悬架的控制，通过仿真研究表明半主动悬架能较好地改善车辆行驶的平顺性和操纵稳定性，同时还证明该策略用于半主动空气悬架控制是可行的和有效的。     

半主动悬架模糊PID混合控制及时滞分析

半主动悬架较被动悬架，在乘坐舒适性、操纵稳定性方面均有较大提高，同时与主动悬架相比具有性价比高、耗能小等优点，所以半主动悬架成为近年来汽车底盘研究的热点。本文基于车辆4自由度1／2半主动悬架模型，提出了模糊PID混合控制算法，并基于该算法对半主动悬架进行控制，且对半主动悬架系统的时滞问题做了定量分析。仿真结果表明，模糊PID混合控制的半主动悬架在车身加速度、车身俯仰角加速度、前后悬架动挠度、前后轮胎动载荷、前后簧载质量加速度等在时域和频域中均有所改善，且一定量的时滞对该算法亦影响较小。这对半主动悬架控制算法的研究和半主动悬架的开发具有较大参考价值。     

基于轴距预瞄的半主动悬架模糊神经网络控制

应用模糊控制和神经网络控制理论,构建了1/2车辆的半主动悬架模型,设计了基于轴距预瞄的半主动悬架模糊神经网络控制系统.对前轮半主动悬架采用以对应处车身垂向加速度为目标的模糊控制,对后轮半主动悬架采用轴距预瞄模糊控制,并利用神经网络来调整模糊控制器的控制规则和隶属度函数.在不同车速下对所建的控制系统分别进行了白噪声和路面脉冲输入的仿真.结果表明,与传统的被动系统相比,轴距预瞄模糊神经网络控制的半主动悬架系统能有效降低车辆振动;与模糊控制的半主动悬架系统相比,质心垂向加速度和后轮对应处车身加速度均有显著减小,较好地改善了车辆的行驶平顺性.     

1／2汽车半主动悬架模糊PID控制器设计与仿真

建立了1／2车体四自由度液压半主动悬架模型及动力学模型,设计了用于该半主动悬架的模糊控制器,并进行了仿真分析。仿真结果表明,具有此模糊控制器的半主动悬架在提高车辆乘坐舒适性和操纵稳定性方面明显优于被动悬架。     

基于TruckSim的重型商用车半主动悬架天棚控制研究

悬架是车辆底盘系统的关键组成部分之一,对车辆平顺性有十分重要的影响。传统的被动悬架无法根据车辆运行工况调整自身阻尼,减振效果有限,半主动悬架能够根据不同的运行工况实时调整自身阻尼,能够有效提升车辆平顺性。文章通过TruckSim和MATLAB/Simulink建立基于天棚控制策略的某重型商用车半主动悬架仿真模型和传统被动悬架仿真模型,并对两种悬架的减振效果进行了对比分析,结果表明,相比传统被动悬架,基于天棚控制策略的半主动悬架能够有效提升车辆平顺性,其中车身加速度均方根值降低22.9%,悬架动挠度均方根值降低15.1%,轮胎动载荷均方根值降低9.8%。     

可调减振器阻尼控制与半主动悬架的试验研究

建立车辆半主动悬架1/4模型,提出可调减振器阻尼控制的实现方法,设计半主动悬架台架试验系统。在可调减振器试验的基础上,建立了可调减振器阻尼与步进电机转角之间的关系。最后,对半主动悬架1/4物理模型进行了台架试验。结果表明,试验系统稳定可靠,阻尼控制易于实现,半主动悬架能较好地适应不同的路面输入,为半主动悬架及控制系统的进一步研究奠定了基础。     

车辆座椅悬架的研究进展

座椅悬架是车辆减振系统的重要组成部分,文章介绍了被动型、半主动型、主动型3种座椅悬架的研究进展,最后总结了3种悬架的优缺点并分析了座椅悬架的发展方向.     

主动悬架的发展和技术现状

介绍了汽车主动悬架与半主动悬架的产生，发展及其优缺点，并就其发展方向做了分析介绍。     

电流变智能半主动悬架模糊PID控制

对带有电流变液智能阻尼器的半主动汽车悬架系统设计了一种模糊PID控制器。将半主动悬架簧载质量的位移及其导数作为模糊控制器的输入，PID控制器的3个增益参数作为其输出，利用电流变液智能阻尼器的阻尼力可随电压变化的特性来使车身的振动降为最小。仿真实验给出了最优被动悬架、固定参数PID控制智能半主动悬架和模糊PID控制智能半主动悬架在不同路面激励情况下的响应曲线。     

基于串联型模糊神经网络的汽车半主动悬架的研究

本文建立了五自由度汽车半主动悬架系统模型，提出一种用于汽车悬 半主动振动控制系统的模糊神经网络方法，对半主动悬架 计算机仿真和结果分析，并通过与被动悬架相比较，证明半主动悬架系统在减少振动，提高汽车平一方面要优于被动悬架。     

Comparison between different sets of suspension parameters and introduction of new modified skyhook control strategy incorporating varying road condition

This study examines the uncertainties in modelling a quarter car suspension system caused by the effect of different sets of suspension parameters of a corresponding mathematical model. To overcome this problem, 11 sets of identified parameters of a suspension system have been compared, taken from the most recent published work. From this investigation, a set of parameters were chosen which showed a better performance than others in respect of peak amplitude and settling time. These chosen parameters were then used to investigate the performance of a new modified continuous skyhook control strategy with adaptive gain that dictates the vehicle's semi-active suspension system. The proposed system first captures the road profile input over a certain period. Then it calculates the best possible value of the skyhook gain (SG) for the subsequent process. Meanwhile the system is controlled according to the new modified skyhook control law using an initial or previous value of the SG. In this study, the proposed suspension system is compared with passive and other recently reported skyhook controlled semi-active suspension systems. Its performances have been evaluated in terms of ride comfort and road handling performance. The model has been validated in accordance with the international standards of admissible acceleration levels ISO2631 and human vibration perception.     

液压半主动悬架的自适应神经网络控制

提出了液压半主动悬架系统的自适应神经网络控制策略 ,分析了系统模型及自适应神经网络控制器的设计和实现 ,并对控制效果进行了仿真研究。结果表明通过这种控制策略可以得到比较好的控制效果。     

Semi-Active Suspension with Preview Using a Frequency-Shaped Performance Index

The objective of this study is to develop a control law for a semi-active suspension for the purpose of ride quality improvement. The semi-active control law is determined by reproducing the control force of an optimally controlled active suspension while suppressing its damping coefficient variation. The performance index of the optimal control for the active suspension is modified to include frequency-shaping by use of Parseval's theorem, which allows us to de-emphasize the effects of particular variables over specific frequency bands.

Through the numerical simulations, it was found that the semi-active suspension may reduce the vertical acceleration of the driver's seat and the sprung mass motions significantly. The road-holding and tire deflections were not affected much.     

Semi-Active Suspension with Preview Using a Frequency-Shaped Performance Index

SUMMARY

The objective of this study is to develop a control law for a semi-active suspension for the purpose of ride quality improvement. The semi-active control law is determined by reproducing the control force of an optimally controlled active suspension while suppressing its damping coefficient variation. The performance index of the optimal control for the active suspension is modified to include frequency-shaping by use of Parseval's theorem, which allows us to de-emphasize the effects of particular variables over specific frequency bands.

Through the numerical simulations, it was found that the semi-active suspension may reduce the vertical acceleration of the driver's seat and the sprung mass motions significantly. The road-holding and tire deflections were not affected much.     

汽车悬架控制技术的发展

现代汽车悬架，要求其在各种行驶条件下提供平顺性和安全性的最佳匹配。但是传统被动悬架，只能保证在一种特定道路和速度下达到最优折衷。为此，开发研制了各种悬架控制技术和方案。介绍了半被动、半主动、慢全主动、全主动四种悬架控制方案和应用，并作了相应的评价。     

Development of a systematic and practical methodology for the design of vehicles semi-active suspension control system

In this paper, a novel systematic and practical methodology is presented for design of vehicle semi-active suspension systems. Typically, the semi-active control strategies developed to improve vehicle ride comfort and stability have a switching nature. This makes the design of the controlled suspension systems difficult and highly dependent on an extensive trial-and-error process. The proposed methodology maps the discontinuous control system model to a continuous linear region, where all the time and frequency design techniques, established in the conventional control system theory, can be applied. If the semi-active control system is designed to satisfy some ride and stability requirements, an inverse mapping offers the ultimate control law. At the end, the entire design procedure is summarised in six steps. The effectiveness of the proposed methodology in the design of a semi-active suspension system for a Cadillac SRX 2005 is demonstrated with road tests results. Real-time experiments confirm that the use of the newly developed systematic design method reduces the required time and effort in real industrial problems.     

汽车半主动悬架的神经网络自适应控制

本文提出了用两个线性神经网络对汽车半主动悬架系统进行在线辨识和控制的策略，介绍了该控制系统中神经网络的在线训练方法，进行了仿真计算和结果分析。     

汽车主动悬架系统状态反馈控制技术研究

车辆的悬架系统对于其舒适性和操纵稳定性都起着关键作用。随着计算机技术和液压伺服元件的发展，出现了主动和半主动悬架系统，在其控制策略具有二次型性能指标的最优控制方法比较成熟。通过建立系统的数学模型和仿真计算，对全状态反馈和被动悬架进行比分析，表明主动悬架采用和有限状态的反馈较全状态反馈有明显优势，是一种比较实用的状态反馈控制方法。     

磁流变半主动悬架研究及实车试验分析

针对车辆半主动悬架系统的整车协调控制,通过悬架动力学模型分析了耦合量的影响,提出了一种主从控制方法。基于自行研制的并联常通孔式磁流变减振器和控制系统开展了实车道路试验。在越野路行驶时,驾驶员坐垫处的加权加速度降低了13.8%~42.6%,车身俯仰角速度降低了21.1%~53.7%;蛇行试验中车身侧倾角速度、角度分别平均降低了65%和38.5%;变道试验中车身侧倾角速度、角度分别平均下降65%和51%。综上所述,研制的磁流变悬架系统显著地提升了车辆的乘坐舒适性、操纵稳定性和行驶安全性。