汽车理论论文

麦弗逊前独立悬架汽车的操纵稳定性研究作者：张俊伟学号：0802020407

摘要

20世纪80年代以来，汽车作为极其重要的交通工具，在交通运输领域和人民日常生活中的地位日益突出。国内、国际汽车市场的竞争变得空前激烈，用户对汽车安全性、行驶平顺性、操纵稳定性的要求越来越高。汽车悬架系统是影响车辆动态特性最为关键的子系统，其中由悬架所决定的汽车车轮定位参数对整车操纵动特性有着直接的影响。悬架的运动学/动力学仿真分析在汽车悬架系统的设计和开发中占有重要的地位。

由于汽车悬架系统是一个复杂的多体系统，其构件之间的运动关系十分复杂，这就给通过传统的计算方法分析悬架的各种特性带来许多的困难。

本论文以机械CAD设计、虚拟样机仿真技术为前题。提出运用虚拟样机仿真软件ADAMS里的CAR模块分析并进行优化汽车悬架的设计方法。

首先，根据悬架各部件之间的相对运动关系和各部件的参数在ADAMS\CAR中建立某轿车的麦弗逊前悬架的三维CAD模型，再加上路面激励，分析悬架参数在汽车行驶中的变化规律。然后利用ADAMS\Jnsight对建立的悬架模型进行结构优化，得到悬架系统结构的优化解。

在上述基础上建立了包括前后悬架、发动机、转向系、前后轮胎等在内的整车虚拟样机仿真模型，并根据我国现行整车操纵稳定性试验标准GB/T6323.1.94～GB/T6323.6-94的要求，编写了用于整车操纵稳定性仿真分析的驱动控制文件(DriverControl Files，缩写为DCF)和驱动控制数据文件(DriverControl Da切Rles，缩写为DCD)，进行了转向盘转角阶跃输入试验、转向回正试验、稳态回转试验、蛇行试验和转向轻便性试验等整车操纵稳定性试验仿真分析，并参照GB/T113047-9l《汽车操纵稳定性指标限值与评价方法》对该轿车的操纵稳定性进行了评价计分。

关键词：汽车悬架，建模，ADAMS，操纵稳定性

ABSTRACT

Since 1980s，the status of automobile has been becoming more and mole outstanding in transportation field and people’s daily lives．The competition of national and intemational automobile markets has become drastic unprecedented，and consumers’demand for safety,handling stability and ride comfort is becoming higher and higher．Automobile suspension system is the most pivotal subsystem that affecting vehicle’s dynamic performances，and the automobile wheel alignment parameters that decide d by suspension has a direct effect to vehicle’s dynamic handling stability．Therefore，the kinematic/dynamic simulation analyses of suspension plays a very important role in suspension's design and exploitation．As suspension system is a complex multi-body system，the movement relation between parts is very complicated，which brings much difficulty for analyzing suspension's performances by traditional calculating methods．Based on mechanical CADdesign and virtual pmtotyping simulation technology, this paper suggested adesign method for analyzing and optimizing vehicle suspension by using virtual prototyping softwareADAMS/CAR．First，build the three—dimensional CAD model of a car’s front Macpherson suspension according to the relative movement relations and parameters of all parts and analyze the suspension parameters’variation rule during driving after adding road actuation．Then optimize the suspension structure and get an optimized result for the uspension system by usingADAMS/Insight．

Based 0n the above，the author built the vehicle virtual prototyping simulating model including the front and rear suspensions，the powertrain，the steering system，the front and lear·tires，wrote the driver control files(abbreviation．dco and driver control data files(abbreviation．dcd)for vehicle handling stability simulation analyzing according to the requirements of the current standards GB/T6323．1-94-GB/T6323．6-94 of onr nation’s for vehicle controllability and stability test,carried out simulation and analyses for vehicle handling stability such as steering wheel angle step input test,leturnability test，steady static circular test，pylon course slalom test and steering efforts test，and evaluated the car’s handling stability performance by scoring according to GB/T 13047-91<>．

Key words：Automobile suspension，modeling，ADAMS，handling stability