【作者】 王国权；

【导师】 余群；

【作者基本信息】 中国农业大学 ， 车辆工程， 2002， 博士

【摘要】 平顺性是现代高速度、高舒适性车辆的一个主要性能，所有新开发的车辆或经过改装的车辆都要进行平顺性分析和试验。传统的分析方法是对车辆进行抽象简化，建立其振动微分方程，通过在频域范围求解预估其平顺性，分析结论都以曲线和数据来表示，缺乏直观性和交互性。计算机技术的发展，虚拟现实技术的逐渐应用，可以实现在计算机上建立汽车产品的三维实体模型和试验道路虚拟场景，使虚拟汽车在虚拟的试验道路上行驶，以三维实体模型的运动体现车辆的平顺性情况。即通过在计算机上“再现”、“体验”试验过程，在产品的设计阶段进行车辆的平顺性试验，为减少开发过程中试验和制造费用提供求解方案。虚拟试验用于车辆平顺性研究，具有理论的深刻性和实际应用的双重意义。围绕车辆平顺性的虚拟试验技术，本文在设计与建立桌面式车辆平顺性虚拟试验系统、建立平顺性动力学分析模型，虚拟场景中车辆平顺性试验的实现，试验数据的再现等方面进行了探索性的工作。 本文采用两种方法建立了车辆平顺性分析的动力学模型：8自由度车辆平顺性分析的微分方程模型，考虑了驾驶员和车体的侧倾，结合随机路面激励的时域模型，在B级路面输入条件下，进行了时域仿真求解，得到车辆和驾驶员在汽车坐标系中各个方位上随时间历程的运动位移；利用ADAMS软件建立的福田小卡汽车，共计596个自由度的三维实体整车虚拟汽车模型，全面地考虑了影响平顺性的各种因素，然后通过对路面功率谱的变换生成适合于ADAMS／Tire的路面文件，实现了整车虚拟样机在随机输入激励下，车辆振动模型的时域仿真求解。 参照道路试验场景，建立了模拟随机道路的包括路面、河流、草地、房屋、树木、山脉等对象的车辆平顺性试验场图形数据库。对图形帧缓存、通道、场景、光照、视点等资源进行设定、编程后，建立了模拟真实世界场景、色彩和光照的虚拟试验场景。使用OpenGVS SDK编程工具，实现了对虚拟试验场景和车辆模型数据库的调用。汽车模型在虚拟道路试验场中行驶时，能够体现车厢(包括驾驶室)的垂向运动、横向运动和俯仰运动；驾驶员的垂向运动、横向运动和俯仰运动，六个轮胎的旋转运动。其运动规律皆由模型分析的数据来驱动确定。从而实现车辆平顺性的振动位移在计算机屏幕上的显示，以图像运动的形式表现车辆的平顺性。 本文还建立了基于虚拟仪器技术的虚拟试验数据再现系统，使得以图像显示的运动能以数据曲线形式再现，为定量分析提供方便。通过与实车道路试验数据的比较，表明虚拟试验有较好的可信性。更多还原

【Abstract】 Ride comfort is one of the prime performances of modern vehicle. The newly developed vehicle must be evaluated and tested before entering into market. The traditional evaluation method is to build the vehicle model with mathematical differential equation, then pre-evaluate its comfort performance in the frequency domain. All the conclusions are interpreted and expressed in curve and data, which is invisual and lack of interactivity. As rapid progress of computer technology and application of virtual reality technology, we can create a 3D vehicle model and a virtual proving test rig in the computer, make the vehicle model run on the virtual testing road, then evaluate its performance. In another word, we can complete the ride comfort testing in computer during the period of product designing, experiencing the testing procedure, thereby the cost on developing and research will be minimized. Based on virtual testing technology of vehicle ride comfort, this dissertation focused on the procedures of setting up the desktop comfort virtual testing system, building ride comfort dynamics analysis model, completing ride comfort testing in virtual ground, etc.In this dissertation, two methods were adopted to build dynamics model for vehicle ride comfort analysis: one is eight freedom vehicle ride comfort differential equation model in which lateral movement of driver and vehicle body was considered. Combined with time domain model of random road input, we got the driver and vehicle’s moving displacement. The other method, we built a Forland truck virtual prototyping using ADAMS, it is a 3D machine model, totally with 596 freedom degrees, every factor that influences the vehicle ride comfort was considered, finally complete the time domain simulation on random road input.We build a ride comfort testing graphics database regarding real proving ground, which contains the objects, e.g. road surface, river, grassland, house, trees, cordillera and so on. After setting and programming resource such as graphic frame buffer, channel, scene, light, camera facility, we built the virtual proving ground, which simulated the real word, real color, and light. Vehicle model database and virtual proving ground was called by OpenGVS SDK program. When the model running on the virtual road, it can show the vertical, lateral and pitching movement of the vehicle body and driver, and the rotation movement of the six wheels, these movements were controlled by model analysis data. Therefore, the vibrating displacement of vehicle was displayed in computer screen.This paper also presented virtual testing data recurrence system based on virtual instrument technology, which can recur the movement graphics as data and curves. Comparing with data obtained from real road testing, the result proved that virtual testing was reliable.更多还原