【作者】 项俊；

【导师】 张云清；

【作者基本信息】 华中科技大学 ， 机械设计及理论， 2005， 硕士

【摘要】 实际轿车系统中大量存在非线性元件,例如弹簧、阻尼器、橡胶衬套以及轮胎等均具有非线性特性。在产品要求精益设计的条件下,轿车建模分析已不满足于线性模型分析,而要求更多地考虑非线性影响。能够全面精确表达和预测轿车各种非线性特性的多体动力学建模方法是进行轿车的动态性能设计的有效手段。本文应用多体力学方法研究了弹簧、阻尼器、缓冲块、橡胶衬套以及轮胎的非线性特性,并在ADAMS软件平台之上,研究了整车非线性多体动力学模型的建立。模型中考虑了车辆的众多细节,各种设计参数可以在模型中得到体现;考虑了前后悬架、转向系统的详细几何结构参数;对于零部件之间的连接,完全按其实际结构,应用ADAMS软件所提供的力约束及铰链约束等工具予以准确反映;对于建模所需的悬架和减振器的刚度、阻尼以及连接处的橡胶衬套,考虑其非线性特性,并将其加入到整车模型中,使模型更接近轿车的实际工况。轮胎模型采用Magic Formula模型。本文利用实车试验记录的信号作为模型仿真的输入,对所建模型进行了多种实车试验验证,有效地验证了模型的正确性、精确性。仿真结果表明所建整车动力学模型具有较高的模型精度,达到实际工程应用要求。在验证模型的正确性和精确性的基础之上,本文对该模型进行了操纵稳定性、平顺性等方面的整车动力学仿真。通过模型的仿真分析可以预测整车操纵稳定性、平顺性等各种动态性能,并可以在此基础之上直接考虑设计参数对性能的影响以及优化整车的动态性能,初步实现了在计算机上对整车系统动力学的几大重要性能的模拟。本文对于轿车的开发设计有着直接的指导作用,从而实现提高产品的设计质量,加快开发速度,降低研发成本。更多还原

【Abstract】 Real vehicle system includes large numbers of nonlinear component ,such as spring ,damper ,rubber bushing ,tire and so on .As the product must be designed precisely, vehicle modeling analysis which will not settle for linear analysis ,but also request more consideration about the influence of the nonlinear characteristic .The dynamics simulation with multi-body system dynamics method which could demonstrate roundly and precisely and estimate the nonlinear characteristic of vehicle .It is an available method to design the vehicle dynamic performance . In this paper ,the nonlinear characteristic of the spring ,damper , rubber bushing and tire has been studied by using multi-body system dynamics . Basing on ADAMS software ,the establishment of the nonlinear full vehicle multi-body dynamics model has been studied. Many details have been considered and different parameters can be demonstrated in the model .Considering the detailed geometric structural parameters of the front and rear suspensions ,steering system etc .According to the real connection of parts ,we apply the tools of forces and kinematic joints which ADAMS software provide to exactly reflect them ,considering the nonlinear characteristic of the stiffness of the spring and dumper ,rubber bushing .The Magic Formula tire model is used in the model. By using the test signal as the steering wheel input ,many different validations of test data was made and the validity and precision of the model was proven .The result shows that full vehicle model has higher precision than the request of the practical application .Basing on the validity and precision of the model ,we make full vehicle dynamics simulation about handling and riding performance .Through the dynamics simulation ,the handling performance ,riding performance of full vehicle can be estimated .Farther we can directly consider the influence of the parameters on the dynamic performance and can optimize the dynamic performance. Accordingly ,we perform the simulation about the several important performance of the full vehicle system dynamics with the computer ,which has directive effect on the development and design of the vehicle .It is of great significance to the reduction of real prototyping manufacture and real laboratory test.更多还原