车辆半主动悬架与助力转向集成控制的仿真研究

为协调车辆操纵稳定性和行驶平顺性,基于底盘系统动力学原理,建立了半主动悬架和电动助力转向的综合模型,对半主动悬架和电动助力转向系统进行集成控制.运用二次反馈法和PID策略分别对悬架的可调阻尼和转向系统的助力进行控制.仿真结果表明,在集成控制情况下,车辆的操纵稳定性和平顺性均优于悬架或转向单独控制的效果.     

电磁主动悬架的设计及仿真研究

基于电磁学原理,利用电磁铁作为主动悬架的作动器,构造出电磁作动器的一般结构。在1/4汽车悬架的基础上,建立了电磁主动悬架的非线性模型,并应用现代控制理论设计了该模型的次优控制器,对该模型进行分析、仿真。模拟结果表明,电磁悬架能够实现一般主动悬架的功能,满足车辆平顺性的要求,可以适用于汽车的悬架系统。     

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。     

7自由度主动悬架整车模型最优控制的研究

应用汽车系统动力学理论,建立了七自由度主动悬架的动力学模型。根据线性二次型最优控制原理设计了主动悬架线性二次型(LQR)控制器,并构建了实现该控制策略的主动悬架控制仿真模型。仿真结果表明:对主动悬架进行最优控制,能够有效地降低车身垂直振动加速度、车身侧倾角加速度和俯仰角加速度。     

液电式主动悬架滑模控制仿真研究

针对一种液电式主动悬架系统,设计了一个滑模控制器,研究了液电式主动悬架系统的幅频特性。首先介绍液电式主动悬架系统工作原理;其次利用MATLAB/Simulink建立了液电式主动悬架系统二自由度仿真模型;最后针对液电式主动悬架系统设计了一个滑模控制器,结合液电式主动悬架系统二自由度动力学模型进行仿真试验。仿真试验表明,基于滑模控制器的液电式主动悬架系统在悬架一阶固有频率处均能够将悬架评价指标有效衰减,在二阶固有频率处也可以取得一些优化。     

被动天棚阻尼悬架降阶与优化

采用基于Routh稳定判据的Pade逼近法对被动天棚阻尼悬架系统进行降阶,寻找阶次低、元件少的ISD悬架结构。建立四分之一悬架模型,运用统一目标函数的遗传算法优化结构的参数,对比分析了传统被动、被动天棚阻尼和降阶ISD三种悬架系统的性能。结果表明,与被动天棚阻尼悬架相比,降阶ISD悬架的车身加速度、轮胎动载荷和悬架动行程均方根值都不同程度逼近被动天棚阻尼悬架,能够实现被动天棚阻尼悬架的主要性能,说明经降阶优化的ISD悬架综合性能可以接近被动天棚阻尼悬架,研究结果从理论上验证了基于Routh稳定判据的Pade逼近法的有效性。     

主动悬架系统的连续模糊控制

在主动悬架系统中，动力装置的控制非常重要。为了能在利用较少的状态量作为反馈信号的条件下达比较理想的控制效果，宜采用连续模型控制方法来实现主动悬架动力装置的控制。模拟计算表明， 该方法可使汽车的行驶平顺性和安全性同时得到有效改善。     

基于多体系统动力学的微型客车操纵稳定性DOE优化设计

利用多体系统动力学软件ADAMS建立了某微型客车动力学模型,并应用该模型对整车操纵稳定性进行了仿真分析.结合仿真数据利用ADAMS/Insight模块对前、后悬架系统中的刚度和阻尼进行了正交DOE优化,通过对优化结果的分析提出前、后悬架系统刚度值和阻尼值的3组合理匹配组合,最后通过3种组合在试验样车上的主观评价结果确定了前、后悬架刚度值和阻尼值.     

油气悬架整车的振动状态观测器设计

针对油气悬架阻尼实时控制中的车身振动状态测量问题,建立了油气悬架整车7自由度振动模型的状态方程,并基于该状态方程设计了油气悬架整车振动状态观测器。该状态观测器以油气悬架油缸压力为输入,以悬架动行程误差作为反馈,通过设计观测器的反馈增益,使得观测器状态能够跟踪被观测车辆的真实状态。状态观测值与试验测试值的对比表明,所设计的状态观测器能够有效观测出油气悬架车辆的振动状态。     

基于平顺性的四轴重型商用车悬架参数优化

为提高车辆行驶平顺性,建立某四轴重型商用车悬架动力学模型,并对悬架参数进行优化。模型中,在车辆结构上考虑了平衡悬架和驾驶室,在悬架力学特性上考虑了阻尼非线性。采用遗传算法对车辆悬架的刚度特性和阻尼特性进行优化,优化综合考虑了车辆在不同路面等级下以不同车速行驶的平顺性。对优化前后驾驶室处垂直加速度均方值进行仿真对比,结果显示,优化后车辆行驶平顺性得到有效提高。     

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.     

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

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.     

非线性液压ISD悬架系统研究

在考虑摩擦、马达阻尼力以及流动压力损失的影响下,研究非线性对液压式惯容器-弹簧-阻尼(ISD)悬架性能的影响。文章建立了两级串联式非线性液压ISD悬架的整车模型,分析了飞轮转动惯量、马达排量、油液实际作用面积以及回流管等效长度这四个非线性参数对液压ISD悬架性能的影响,在仿真的基础上,进行了液压ISD悬架的整车台架试验研究,验证了非线性模型的正确性。研究结果可建立精确的非线性液压ISD悬架系统模型,为进一步提高主动、半主动ISD悬架的控制的有效性提供了支撑。     

Control Algorithms for Active Cab Suspensions on Agricultural Tractors

This paper describes active agricultural tractor cab suspensions based on optimal control theory. Control algorithms based on time invariant state feedback and on adaptive control are developed and studied. The influence of different observers and measurement noise levels on the vibration damping capacity are studied as well as the power consumption for the suspensions.

The principle for the adaptive algorithm is based on the parameters in the penalty matrices being varied so that the resulting controller always strives to make optimum use of available travel space. The feedback and observer gains are also changed depending on the characteristics of the vehicle's frame movements.

The results show that it is possible to design an effective active suspension, but that the choice of feedback gains must be dependent on the surface characteristics to reach satisfactory vibration damping performance.     

电液主动悬架滤波输出反馈控制器的设计及仿真实现

基于1／2车辆模型和非线性电液作动器，提出并详细设计了主动悬架滤波输出反馈控制器。整个主动悬架系统分解为内、外两个回路，外回路采用滤波输出反馈控制，大幅度衰减了车辆在高低频范围内的起伏和俯仰运动，提高了车辆的乘坐舒适性。内回路基于非线性作动器模型，采用传统的PI控制器，较好地跟踪输出了控制系统需要的作用力。此外，还对作动系统的摩擦力进行了详细建模。频域和时域仿真结果演示了主动悬架的良好性能并验证了结论。     

Active Damping in Road Vehicle Suspension Systems

Low order, linearized dynamic models of road vehicle suspension systems are analyzed to provide insight into the benefits of suspensions incorporating generalized velocity feedback compared with conventional passive suspensions. Damping forces from passive dampers are supplemented by forces generated by an active element requiring a power supply. A simple criterion is developed which indicates whether or not the introduction of activedamping forces will result in significant benefit for pneumatic tired vehicles.

An extended active suspension concept involving a high-gain load leveler as well as active damping is analyzed. The realization of active or semi-active damping forces through electrical or hydraulic means is briefly discussed.     

基于1/2车辆模型的主动悬挂滤波输出反馈控制研究

基于1 2车辆模型,在分析被动悬挂弹簧和阻尼系数对车辆舒适性影响的基础上,提出并深入研究滤波输出反馈控制策略。研究表明,在对悬挂弹簧和阻尼系数进行主动滤波的基础上,采用输出反馈控制,能大幅度衰减车辆在低于和高于车轮频率范围内的车体起伏和俯仰运动,提高车辆的乘坐舒适性。仿真结果演示了主动悬挂的性能并验证了结论。     

四级阻尼可调式液压互联悬架系统性能研究

提出了一种新型四级阻尼可调式液压互联悬架 （FDAHIS） 系统。FDAHIS系统在被动液压互联悬架系统的阻尼阀上并联了两个常通孔面积不同的电磁开关阀,通过反馈控制策略控制电磁阀开闭状态,调节系统液压流量,从而实现阻尼四级可调。为了研究该系统性能,建立FDAHIS系统模型和七自由度整车模型。通过系统单元台架试验对该模型进行了验证。整车仿真结果表明,与被动的液压互联悬架 （HIS） 系统相比,FDAHIS系统在车辆行驶平顺性和抗俯仰性能方面表现更佳。