基于ADAMS／CAR的某轿车悬架优化设计

汽车悬架系统为一多体系统，部件之间的运动关系十分复杂，传统的人工计算很难将悬架的各种特性表述清楚。以国产某轿车为例，应用多体运动学与动力学仿真软件ADAMS中的CAR专业模块建立该车的前后悬架多刚体模型，对其悬架的各种性能进行了仿真分析，研究了悬架几何参数对汽车操纵稳定性的影响，在理论验证的基础上揭示了该悬架的运动规律，在进行优化分析的同时还提出了改进的意见。     

悬架转向特性的汽车操纵稳定性分析

为进一步改善汽车直线行驶稳定性及转向行驶特性，近年来，人们对悬架系统的导向功能给予了更多的关注，具有转向功能的悬架系统相继得到发展。钢板弹簧县架系统“轴转向”效应的应用；前后轮转向主动控制的四轮转向（４ＷＳ）系统；以及使悬架系统具有合适的变形转向功能，其中，多链节（多连杆）悬架结构和雪铁龙ＺＸ系列轿车的随动悬架便是代表。本文对这些结构各异的悬架系统的转向特性进行了对比分析，着重分析了雪铁龙ＺＸ系列     

重型牵引车空气悬架系统减振器最佳阻尼特性匹配

车辆悬架系统的阻尼决定车辆悬架的特性,对车辆行驶平顺性和安全性具有重要影响。为了设计车辆的最佳减振器,利用悬架系统的最佳阻尼比,分析前后悬架系统减振器最佳阻尼系数,建立减振器最佳速度特性数学模型。利用多体动力学软件ADAMS/Car模块建立了重型牵引车整车刚柔耦合多体动力学模型,进行整车平顺性仿真分析和悬架系统动力学仿真。匹配结果表明,对该悬架系统,减振器所做的匹配设计是正确有效的,改善了悬架系统的运动特性和整车平顺性。     

用柔性多体动力学方法预测悬架对汽车转向特性的影响系数

利用柔性多体动力学方法建立了基于ADAMS软件平台的麦弗逊式独立悬架动力学仿真分析模型。并根据所建立的模型，对某轿车麦弗逊式前独立悬架的力变形特性进行了仿真和试验对比分析。通过仿真计算出了决定汽车不足转向度相关参数的相关系数。     

采用多体系统动力学的平衡悬架牵引车平顺性研究

采用多体系统动力学理论及相应软件ADAMS，对具有平衡悬架的3轴牵引车平顺性进行研究。建立了其多体系统动力学模型，并经过二次开发形成一套能够进行参数化自动建模的软件系统。对仿真模型进行时域、频域的仿真分析，并研究平衡悬架的一些主要设计参数对平顺性的影响。     

应用于车辆实时动力学仿真的悬架模型

针对车辆动力学实时仿真的要求提出一种新的悬架建模方法。将悬架系统视为车身与车轮之间的无质量复合约束，利用悬架杆系的多体运动学模型和准动力学模型来分析悬架系统的运动和力学传动特性，从而悬架动力学问题简化为代数方程组的求解。与基于侧倾／力矩中心理论建立的等交悬架模型相比，该方法可分析悬架杆系内部作用力，并能更准确地描述悬架在水平方向的约束作用；与应用传统多体动力学理论建立的模型相比，该方法解决了仿真实时性的问题。基于这种方法建立了国产某轿车麦弗逊式悬架模型，并将仿真结果和道路试验及ADAMS仿真结果进行了对比，有较好的一致性。     

基于ADAMS／Insight的多连杆后悬架系统优化分析

在对某型轿车多连杆后悬架系统建立ADAMS多体动力学模型基础上,对该悬架系统进行了仿真分析,分析了轮跳对后轮定位参数的影响,并结合ADAMS／Insight模块对该悬架部分硬点的位置进行了DOE优化。优化结果表明,对该悬架系统所做的优化设计是正确有效的,改善了该悬架系统的运动特性。     

扭杆弹簧独立悬架刚度计算分析

以虚位移原理和多体系统动力学理论为基础,介绍了扭杆弹簧独立悬架垂向线刚度理论公式的推导过程,系统的分析悬架刚度非线性特点,并详细介绍了扭杆扭矩对悬架刚度计算结果的影响。     

柔性体衬套模型对四连杆悬架K&C特性的影响

基于柔性多体系统动力学的基本思想,提出了一种充分考虑衬套在不同方向上刚度耦合的新柔性体悬架衬套模型.采用模态综合法计算出变形量,解算出衬套模态.然后生成模态中性文件,并导入ADAMS/Car中以建立四连杆悬架的刚柔耦合动力学模型,并进行仿真和实车试验.结果表明,所采用的衬套柔性体模型要比传统衬套模型更精确,能在设计阶段更真实地预测与分析汽车悬架的性能.     

多连杆悬架与双横臂悬架运动学和弹性运动学特性分析

改进了某轻型客货两用车双横臂式前悬架系统为多连杆悬架系统,运用多体动力学软件ADAMS/CAR建立了该双横臂与多连杆前悬架及转向系统的虚拟样机模型。采用轮跳方法、加载地面制动力和侧向力方法,对两种悬架系统进行了运动学与弹性运动学特性仿真对比分析。结果表明,多连杆悬架对车身的侧倾和纵倾、车轮定位及顺从转向效应等都比双横臂悬架具有较好的抑制作用,有利于提高汽车操纵稳定性。     

Aeroelastic Effects in Multibody Dynamics

To enable a realistic assessment of the aeroelastic phenomena of aircraft, a simultaneous application of computational fluid dynamics (CFD), computational structural mechanics and flight mechanics has to be performed. Each discipline has developed powerful specialized tools which have to be adapted for multidisciplinary applications. The combination of CFD and elastic multibody systems is well suited for the simulation of a range of aircraft applications, especially for aircraft ground dynamics. Approaches to a coupling of elastic multibody systems and computational fluid dynamics have been performed using close coupling, that is a modal approach, and loose coupling, that is by co-simulation. In the article the applied programs and the coupling methods are presented. Advantages and limits of using multibody simulation as compared to the direct use of FEA methods for the representation of structural dynamics are discussed. Results of coupled steady and unsteady simulations are presented. Finally, an approach to the aeroelastic trim problem is shown.     

Aeroelastic Effects in Multibody Dynamics

To enable a realistic assessment of the aeroelastic phenomena of aircraft, a simultaneous application of computational fluid dynamics (CFD), computational structural mechanics and flight mechanics has to be performed. Each discipline has developed powerful specialized tools which have to be adapted for multidisciplinary applications. The combination of CFD and elastic multibody systems is well suited for the simulation of a range of aircraft applications, especially for aircraft ground dynamics. Approaches to a coupling of elastic multibody systems and computational fluid dynamics have been performed using close coupling, that is a modal approach, and loose coupling, that is by co-simulation. In the article the applied programs and the coupling methods are presented. Advantages and limits of using multibody simulation as compared to the direct use of FEA methods for the representation of structural dynamics are discussed. Results of coupled steady and unsteady simulations are presented. Finally, an approach to the aeroelastic trim problem is shown.     

Flexible multibody simulation of automotive systems with non-modal model reduction techniques

The stiffness of the body structure of an automobile has a strong relationship with its noise, vibration, and harshness (NVH) characteristics. In this paper, the effect of the stiffness of the body structure upon ride quality is discussed with flexible multibody dynamics. In flexible multibody simulation, the local elastic deformation of the vehicle has been described traditionally with modal shape functions. Recently, linear model reduction techniques from system dynamics and mathematics came into the focus to find more sophisticated elastic shape functions. In this work, the NVH-relevant states of a racing kart are simulated, whereas the elastic shape functions are calculated with modern model reduction techniques like moment matching by projection on Krylov-subspaces, singular value decomposition-based reduction techniques, and combinations of those. The whole elastic multibody vehicle model consisting of tyres, steering, axle, etc. is considered, and an excitation with a vibration characteristics in a wide frequency range is evaluated in this paper. The accuracy and the calculation performance of those modern model reduction techniques is investigated including a comparison of the modal reduction approach.     

Performance investigation of vehicle suspension system with nonlinear ball-screw inerter

This paper investigates the influence of ball-screw inerter nonlinearities on the vibration isolation performance of the vehicle suspension system. That is achieved by building a nonlinear mechanics model of the ball-screw inerter with friction in ball-screw assembly and elastic effect of screw. The parameters of the nonlinear mechanics model are identified using recursive least squares algorithm based on test data. Then, the nonlinear ball-screw inerter is applied to vehicle suspension analysis of the half-car model with three passive suspension layouts. The performance of the vehicle suspension system with the nonlinear ball-screw inerter is compared with that with the linear inerter. It is demonstrated from the results that the vibration isolation performance of the vehicle suspension system is slightly influenced by considering the ball-screw inerter nonlinearities in general. The influence of the ball-screw inerter nonlinearities on every performance indicator for different suspension layouts is discussed finally.     

五连杆悬架的刚体运动学和弹性运动学分析

探讨了基于矢量分析原理进行五连杆悬架的刚体运动学和受力分析的方法,并进一步提出了一种考虑橡胶衬套弹性的悬架弹性运动学迭代计算方法。据此编制了相应的计算机程序,进行了一种轿车五连杆后悬架的刚体运动学和弹性运动学模拟分析,探讨了悬架橡胶衬套的弹性对车辆性能的影响。该方法有效简捷,可方便地应用于五连杆悬架设计分析和参数优化。     

Multiphysic modelling of railway vehicles equipped with pneumatic suspensions

This article presents a multidisciplinary approach of railway pneumatic suspension modelling: both multibody and pneumatic aspects are taken into account. The work aims at obtaining a realistic model of the secondary suspension and coupling it with a multibody model of a train. Various components of the pneumatic circuit such as bellows, tanks, pipes and valves are taken into account. The article focuses on the bellow-pipe-tank subsystem for which several modelling approaches are presented and compared. Differences between differential and algebraic models are highlighted, and an application-dependent choice between them is suggested. A complete model of the pneumatic circuit is then obtained and coupled with a multibody model of the train. As a result, the behaviour of a suburban train equipped with a pneumatic secondary suspension is analysed, in particular undesired oscillating motions which affect the comfort. Topological modifications and improvements of the suspension are also investigated and discussed.     

四连杆式独立悬架性能分析

四连杆式悬架是技术比较先进的悬架形式,可以从设计上保证车辆良好的直线行驶性能并最大程度减轻载荷的影响。通过对一般结构悬架的力学分析,总结了车辆在纵向与侧向运动特性要求下的悬架设计规则,同时建立了四连杆式悬架多刚体系统模型并对杆件位置姿态和车轮定位参数等特性进行了仿真,经过数值处理获得了四连杆悬架的各项性能。最后还通过对比麦弗逊式悬架,说明了前者的优势所在。     

Multiphysic modelling of railway vehicles equipped with pneumatic suspensions

This article presents a multidisciplinary approach of railway pneumatic suspension modelling: both multibody and pneumatic aspects are taken into account. The work aims at obtaining a realistic model of the secondary suspension and coupling it with a multibody model of a train. Various components of the pneumatic circuit such as bellows, tanks, pipes and valves are taken into account. The article focuses on the bellow–pipe–tank subsystem for which several modelling approaches are presented and compared. Differences between differential and algebraic models are highlighted, and an application-dependent choice between them is suggested. A complete model of the pneumatic circuit is then obtained and coupled with a multibody model of the train. As a result, the behaviour of a suburban train equipped with a pneumatic secondary suspension is analysed, in particular undesired oscillating motions which affect the comfort. Topological modifications and improvements of the suspension are also investigated and discussed.     

汽车悬架系统磁流变减振器的数学模型及其试验研究

基于磁流变减振器的汽车悬架系统具有明显的滞后非线性,系统中的非线性阻尼和非线性刚度等对其动力学行为产生了很大的影响。影响汽车平顺性的主要因素是车身的垂直振动。为了描述这种振动,建立了汽车悬架系统的力学模型及其动力学方程,并结合阻尼特性试验,利用不同的数学模型描述了磁流变减振器的非线性滞后特性和饱和特性。