【作者】 侯宇明；

【导师】 周济； 金国栋；

【作者基本信息】 华中科技大学 ， 机械设计及理论， 2011， 博士

【摘要】 指标分解方法对于商用车这样的复杂工程产品系统来说是一种层次化的设计方法,该方法可以使产品研发流程更加有序化,便于研发流程的量管理。本文以商用车为研究对象,实现了基于指标分解的设计与优化方法的具体细节,形成了基于该方法的研发流程的主要环节,主要研究包括以下内容：1)研究了虚拟样机技术中三种板簧建模方法——有限元法、SAE三连杆法和离散梁法的建模原理,并对三种建模方法进行了深入的研究比较,在SAE三连杆法的基础上提出了一种改进的SAE三连杆法板簧建模方法,该方法具有模型参数少、精度高等优点。2)按照指标分解方法的理论体系,使用指标分解方法对三轴商用车平顺性和操纵稳定性进行了联合优化,详细阐述了指标分解方法各层次建立的步骤和指标传递过程,以及改善优化效果的相应措施。3)指标分解传统方法应用于大型工程实例中,往往会产生系统指标难以继续传递的弊端。为了增强指标分解方法应用的广泛性,文中提出了一种新的指标分解方法——指标分解扩展方法。通过概念悬架模型以及SAE三连杆法板簧的使用,把概念悬架整车模型的输入曲线与多体子系统模型的K&C曲线联系起来,板簧的刚度曲线与自身结构尺寸联系起来,解决了子系统层设计变量难以继续下传至零部件层的问题,同时提高了仿真精度。4)建立了商用车整车多体模型,并对该仿真模型的有效性进行了验证,并在此基础上对优化前后整车层评价指标进行了对比,结果表明应用ATC扩展方法进行优化,整车层的操纵稳定性和平顺性都不同程度得到了改善。本文按照指标分解方法的理论体系,结合中国商用车研发的实际状况,重新构造了商用车研发的模型体系,该模型体系能够使商用车的研发流程更加具有层次性,使其研发过程更加规范化,从而提高商用车的研发品质与研发效率。创新地实现了基于指标分解方法的商用车开发流程,该流程不仅可以提高开发效率,并且由于该流程可以提供量化的子系统性能指标,因此对研发流程的“目标门管理”具有极大的促进作用。更多还原

【Abstract】 Analytical Target Cascading(ATC), which is a hierarchical method for designing engineering product of complex large system, like commercial vehicle, it can make the R&D process more neatly and methodically arranged and more conveniently for quantification management.This thesis elaborates the process of forming main procedures of optimal design method based on ATC for commercial vehicle in detail. The main research contents are listed as follows:Modelling theory of three methods to build leafspring based on Virtual Prototyping Technology are studied and compared. A new improved method based on SAE three-link modeling is proposed. This new method is proved with more advantage such as requiring fewer parameters and with higher simulation accuracy.According to the theoretical system of ATC, performances of handling and ride characteristics of tri-axle commercial vehicle are optimized simultaneously. Modelling of each hierarchy in the optimization problem and its process of target cascading are dealt with specifically. Besides, method of improving the effectiveness of ATC is also presented.Although ATC has an enormous application potential to solve various engineering problems, there also exists a drawback of passing system targets down to the subsystem continuously. In order to widen the range of application, a new ATC method, ATC extended method is put forward. By the application of conceptual suspension and Three-Link Leafspring Model, input curves of full vehicle of conceptual suspension and K&C curves of multibody subsystem, stiffness curves of leafspring and its structure dimensions are related. Thus, design variable of the multibody subsystem can be cascaded down to the part level successfully, with the enhancement of simulation accuracy.Multibody models of full vehicle are built in ADAMS and the verification of the model is conducted with the test data. Objectives of the vehicle before and after the optimization are compared. It reveals that the performances of handling and ride characteristic of tri-axle commercial vehicle are improved to various extents after optimization using ATC extended method.According to the theoretical system of ATC as well as taking present status of research on commercial vehicle in China into consideration, this thesis rebuild a model system of commercial vehicle for research. This system can make the research process highly organized and standardized. Thus, quality and efficiency for research and development are enhanced to a great extent. This dissertation presents the development process for designing commercial vehicle based on Analytical Target Cascading method innovatively. This process is beneficial to enhance the efficiency of development. Besides, it greatly promotes the progress towards’target gate management’ during the R&D process owing to the quantification performance targets of subsystems.更多还原