基于主动自适应悬架系统的道路友好性研究

为了减少车辆轮胎动载荷对道路路面的影响,提高车辆的道路友好性,设计了以主动悬架为控制对象的自适应模糊PID控制系统。该系统将模糊控制与常规PID控制有机融合,利用模糊隶属函数实时对PID控制参数进行调节。建立5自由度主动悬架友好路面仿真模型,以C级路面谱为路面输入信号,道路友好性评价指标采用动载荷系数、动态载荷应力因子及95百分位4次幂和力,对主动自适应悬架系统进行研究。研究结果表明:采用自适应模糊PID控制的主动悬架系统的道路友好性明显优于被动悬架和单一模糊控制的主动悬架;采用模糊PID控制的主动悬架系统可显著降低车辆对路面的动态载荷,提高道路的使用寿命,最终达到提高公路设计的质量和安全性的目的。     

汽车可控悬架发展综述

悬架是车辆的一个重要组成部分，对于车辆的乘坐舒适性、操纵稳定性等性能有很大影响。因此，根据汽车行驶的路面、工况和载荷等情况来控制自身工作状态，使汽车的整体行驶性能达到最佳的可控悬架系统得到了关注和发展，文中对不同悬架系统的原理和发展进行了介绍。     

车辆主动悬架自适应模糊PID控制

针对车辆悬架系统的动态特性,将现代控制理论运用于主动悬架控制,提出一种新的控制策略———自适应模糊PID控制,并通过仿真验证了其可行性及有效性。这种新型智能控制策略为车辆主动悬架控制理论的研究提供了一条新思路。     

车辆主动悬架的神经网络模糊控制

利用神经网络来实现在车辆主动悬架中的模糊控制，通过对主动悬架实体装置的台架实验研究，在不同激励信号的作用下，神经网络模糊控制器都具有很好地抑制车体振动的特点，其控制效果明显优于PID控制。在车辆主动悬架中，神经网络模糊控制具有设计新颖，实用性强，特别对于减振效果要求较高的车辆，更能发挥其优点。     

主要类型可控悬架的原理简介及发展

悬架是车辆的一个重要组成部分，对于车辆的乘坐舒适性，操纵稳定性等性能有很大影响，因此，一些能够根据汽车行驶的路面、工况和工荷等情况来控制自身工作状态，使汽车的整体行驶性能达到最佳的可控悬架系统得到了人们的广泛关注和发展，中对不同悬架系统的结构和原理进行了介绍，并对目前悬架设计中存在的问题和研究的方向进行了总结。     

基于T-S模糊方法的车辆主动悬架多目标控制研究

为了研究因曲线运动引起的车辆侧翻及防测翻控制方法,提升车辆在不平整道路上的平顺性及紧急避障转向操纵下侧倾稳定性,采用Takagi-Sugeno(T-S)模糊建模方法,设计了主动悬架自适应多目标鲁棒控制策略。分析了基于车辆运动状态的模糊隶属度函数选择方法,当车辆直线行驶或动挠度较小时,保证车辆的行驶平顺性,当车辆发生极限转向或动挠度较大时,限制悬架相对运动量,增强对车身的垂向支撑。以优化加速度H_∞性能及悬架动挠度为控制目标,通过使用并行分布补偿方法将结果优化问题转换为线性矩阵不等式求解问题,确定反馈控制增益。采用自适应鲁棒控制(Aaptive Robust Control-ARC)保证系统在非线性、不确定性下,控制力跟踪的鲁棒性。通过SIMULINK~?及CARSIM~?联合仿真对主动悬架平顺性及侧倾稳定性控制效果进行验证,结果表明:该控制方法可以有效提升在良好路面正常行驶工况下车辆的平顺性,和被动悬架相比,小激励工况下,其加速度峰值降低了70%以上,在大激励下动挠度峰值相比被动悬架降低了15%以上。在随机路面输入下,车辆质心加速度均方根值相较被动悬架降低了4%以上,后轴悬架动挠度峰值降低近20%。当车辆发生侧翻危险工况时,基于T-S Fuzzy的主动悬架可以有效地增加车辆悬架支持力,减小车辆侧倾角,避免车辆发生侧翻。     

汽车非线性半主动悬架的模糊神经网络控制

考虑磁流变减振器阻尼力和悬架弹性元件非线性特性，建立车辆6自由度的半主动悬架非线性动力学模型。提出了一种基于模糊神经网络系统结构的模型参考自适应控制方法来研究汽车半主动悬架的非线性控制问题，并考虑半车模型前后悬架的输入时滞，对其进行了仿真研究。研究结果表明：运用模糊神经网络非线性控制方法能够使人体和车身垂直加速度、俯仰角加速度都得到很大的衰减，证实这种模糊神经网络控制方法可大大减少路面对车身的振动冲击，提高汽车行驶平顺性。     

改进的模糊PID控制器对4自由度主动悬架振动控制的研究

建立了4自由度1／2车体力学模型,针对车辆悬架为一非线性、时滞、不确定系统,设计了一种改进的主动悬架模糊PID控制器。以SANTANA2000实车悬架为仿真参数,以阶跃信号激励为路面输入,在Matlab中进行了时域仿真。结果表明,改进的模糊PID控制的主动悬架对车身垂直加速度、悬架动挠度、轮胎动载荷等平顺性指标改善明显．响应达到稳定状态的时间也有了显著的缩短,车辆乘坐的舒适性和操纵稳定性优于被动悬架和单纯的模糊控制的主动悬架,对车辆主动悬架控制的开发具有参考价值。     

主动悬架的操纵稳定性控制研究

本文分析主动悬架力对车辆操纵稳定性的影响关系,及基于模糊滑模控制方法,设计以提高操纵稳定性为目标的主动悬架控制器。并进行仿真试验验证该控制器的有效性。结果表明该主动悬架控制器能够提高车辆横向操纵性能。     

多轴重型货车悬架系统改进天棚控制策略的研究

依据车辆动力学原理和虚拟样机技术,运用ADAMS构建了四轴重型货车-路面系统的仿真模型,并通过实车平顺性实验验证其正确性;选择合理匹配的空气悬架替换驱动轴平衡悬架,初步改善了车辆道路友好性和平顺性;在考虑减振器力学特性的基础上,同时采用ADAMS和Matlab/Simulink对四轴重型货车虚拟样机悬架系统的半主动改进天棚控制进行联合仿真.以控制参数为变量设计正交试验,通过极差与方差分析确定使车辆道路友好性和平顺性综合最优的控制参数.仿真结果表明,相对于半主动天棚控制,半主动改进天棚控制可有效改善轮胎的动载荷和垂向振动,且对路面等级的变化具有较强的稳健性.     

路面连续减速带下汽车悬架的混沌振动分析

针对汽车通过连续减速带时所产生振动,采用二自由度非线性悬架系统为研究对象,分析其混沌动力学行为,从而实现对系统混沌进行抑制.通过分析高速公路上特殊路段连续减速带的参数和设置方式,建立其静态激励模型和得出动态激励相关函数,以数值仿真研究了非线性汽车模型在此激励下的混沌振动,获得导致系统发生混沌振动的频率条件,及车速、减速...     

电控空气悬架系统综述

随着车辆控制技术的发展,电控空气悬架系统逐步取代了传统空气悬架.文章介绍了电控空气悬架系统的结构组成及其功能特点,概述了国内外电控空气悬架的发展情况,简要分析了其发展趋势.与传统弹簧悬架相比,电控空气悬架系统具有较优越的动态传递特性,能降低车轮与路面之间的相对动载,减少汽车对路面的冲击损坏,较好地改善汽车的行驶平顺性和操纵稳定性.     

汽车磁流变非线性悬架模糊控制

建立了整车悬架系统的三维模型,根据试验数据得出了前后悬架弹簧的非线性特性曲线。前后悬架减振器均采用磁流变减振器,采用Bouc-Wen参数化模型为其阻尼力模型。采用模糊控制算法为整车半主动控制算法,采用ADAMS和Matlab联合对整车平顺性进行仿真。结果表明,采用模糊控制算法控制磁流变非线性悬架可提高整车的平顺性。     

汽车可控悬架系统的研究进展

总结了汽车可控悬架的发展状况,详细阐述了半主动悬架、主动悬架等的结构形式及国内外最新研究成果,提出了新型可能量再生的可切换的主动/半主动悬架结构方案,并进行了台架试验。评价了用于可控悬架的主要控制策略,指出应着重研究非线性控制与智能控制方法的综合运用,研究和开发可能量回收的汽车智能悬架,重点包含制动、转向、可控悬架的底盘集成控制。     

Optimal Adaptive Active Suspensions for a Full Car Model

In order to present a useful method for designing active suspension of a vehicle, a linear full-car model is used in this investigation. In this model, the dampers of passive system are totally replaced by actuators. The actuators are controlled with optimal full state vector feedback. After determining feedback coefficients, the responses of active and passive systems were compared and it was found that performance of active system is much superior. It is desired that, changes in vehicle parameters would not affect the system's performance and hence should not violate its optimality. In other words, the system should behave adaptively using Model Reference Adaptive Control. The optimally controlled active suspension was used as a model for the active suspension of vehicle. In this way, the suspension of vehicle is controlled in such a way that its output approaches to that of the optimal active model. Thus the suspension should behave just like the optimal one.     

Performance of Low-bandwidth, Semi-active Damping Concepts for Suspension Control

Active damping has been shown to offer increased suspension performance in terms of vehicle isolation, suspension packaging, and road-tire contact force. It can even approximate the performance of full state feedback control without requiring the difficult measurement of tire deflection. Many semi-active damping strategies have been introduced to approximate the response of active damping with the modulation of passive damping parameters. These strategies have typically required a relatively high bandwidth for actuator response. This paper investigates the simulation performance and “frequency response” of two concepts in low-bandwidth semi-active suspension control, one that sets a damping force directly and another that sets the damping resistance. The electronically controlled bandwidth of these actuators is approximately an order of magnitude less than other semi-active devices; high frequency control is handled mechanically. A quarter-car model is studied with the controlled damping replacing both passive and active damping of typical control schemes. Both low-bandwidth damping strategies perform remarkably well compared to both active and high-bandwidth, semi-active damping. In certain dynamic performances, the new semi-active strategies outperform active damping and what the author calls “nominal” semi-active damping.     

Performance of Low-bandwidth,Semi-active Damping Concepts for Suspension Control

Abstract

Active damping has been shown to offer increased suspension performance in terms of vehicle isolation, suspension packaging, and road-tire contact force. It can even approximate the performance of full state feedback control without requiring the difficult measurement of tire deflection. Many semi-active damping strategies have been introduced to approximate the response of active damping with the modulation of passive damping parameters. These strategies have typically required a relatively high bandwidth for actuator response. This paper investigates the simulation performance and “frequency response” of two concepts in low-bandwidth semi-active suspension control, one that sets a damping force directly and another that sets the damping resistance. The electronically controlled bandwidth of these actuators is approximately an order of magnitude less than other semi-active devices; high frequency control is handled mechanically. A quarter-car model is studied with the controlled damping replacing both passive and active damping of typical control schemes. Both low-bandwidth damping strategies perform remarkably well compared to both active and high-bandwidth, semi-active damping. In certain dynamic performances, the new semi-active strategies outperform active damping and what the author calls “nominal” semi-active damping.     

Optimal Performance of Variable Component Suspensions

Most vehicle suspension systems use fixed passive components that offer a compromise in performance between sprung mass isolation, suspension travel, and tireroad contact force. Recently, systems with discretely adjustable dampers and air springs been added to production vehicles. Active and semi-active damping concepts for vehicle suspensions have also been studied theoretically and with physical prototypes. This paper examines the optimal performance comparisons of variable component suspensions, including active damping and full-state feedback, for “quartercar” heave models. Two and three dimensional optimizations are computed using performance indicators to find the component parameters (control gains) that provide “optimal” performance for statistically described roadway inputs. The effects of performance weighting and feedback configuration are examined. Active damping is shown to be mainly important for vehicle isolation. A passive vehicle suspension can control suspension travel and tire contact force nearly as well as a full state feedback control strategy.     

Optimal Performance of Variable Component Suspensions

SUMMARY

Most vehicle suspension systems use fixed passive components that offer a compromise in performance between sprung mass isolation, suspension travel, and tireroad contact force. Recently, systems with discretely adjustable dampers and air springs been added to production vehicles. Active and semi-active damping concepts for vehicle suspensions have also been studied theoretically and with physical prototypes. This paper examines the optimal performance comparisons of variable component suspensions, including active damping and full-state feedback, for “quartercar” heave models. Two and three dimensional optimizations are computed using performance indicators to find the component parameters (control gains) that provide “optimal” performance for statistically described roadway inputs. The effects of performance weighting and feedback configuration are examined. Active damping is shown to be mainly important for vehicle isolation. A passive vehicle suspension can control suspension travel and tire contact force nearly as well as a full state feedback control strategy.     

汽车主动悬架的单神经元自适应控制

在1/4汽车动力学模型的基础上,设计了汽车主动悬架的自适应神经元控制器。以车辆的行驶平顺性为主要控制目标,车身垂直加速度、悬架动挠度、车轮动位移为具体评价参数,研究了系统在随机路面激励条件下的时域响应,计算了振动响应的均方根值,考察了在变参数条件下控制器的鲁棒性。仿真结果表明,该控制器能有效改善车辆的综合性能,尤其是平顺性和舒适性,并且具有较好的鲁棒性,对模型参数的变化有一定的适应性。