【作者】 王永山；

【导师】 陆敏恂； 王玉新；

【作者基本信息】 同济大学 ， 机械设计及理论， 2007， 博士

【摘要】 产品快速创新设计及其自动化是未来企业在快速多变的市场中取得生存的关键。为此，本课题组提出了基于三维设计平台的产品快速创新设计理论体系，并已基本完成了机械系统符号方案的自动生成、符号方案的自动识别、各种基本机构库的建立等工作。基于前期工作，本文对快速创新设计理论体系的后续模块，即与符号方案对应的含约束复杂机械系统自动化空间布局设计和自动化虚拟装配设计进行了深入研究。此外对创新设计理论体系中的美学设计进行了研究，提出了一种产品外形美学设计方法。主要内容如下：(1)本文给出了一种适合复杂机械系统的空间布局表达方法，该方法包括基本机构的连接关系表达和基本机构的空间位置表达。首先分析了基本机构的各种组合方式，提出了适合于机械系统空间布局的3种基本机构连接关系，并给出了对应的三种布局模型。根据基本机构输入输出轴的特点，建立了一种适合各种基本机构的长方体布局模型，实现基本机构空间位置描述。在此基础上，研究了各种类型基本机构布局空间的确定方法，并编制程序实现了布局参数的自动生成。(2)基于前期符号识别结果，研究了含约束的复杂机械系统自动化空间布局优化算法。根据含约束复杂机械系统的特点，建立了适合于空间布局优化的数学符号模型。采用自适应遗传算法，将机械系统中各基本机构的布局干涉情况、连接关系以及输入输出轴方向和夹角约束等作为构造适应度函数的重要组成部分，利用十进制编码中的整数编码方法对各基本机构编码生成初始种群，通过选择、交叉、变异等操作，实现了复杂机械系统的空间布局优化。(3)采用面向对象技术及SolidWorks二次开发技术，基于“后台预置”装配方法，实现了对应上述符号方案布局优化结果的复杂机械系统自动化虚拟装配。通过读取布局优化模块存储的各基本机构相对布局系统全局坐标系的坐标变换矩阵，并依据基本机构布局模型的第一构件坐标系与基本机构三维实体模型坐标系的差异，对其坐标变换矩阵进行适当修正后，采用“后台预置”装配技术将组成复杂机械系统的各基本机构“预置”到特定的布局空间，从而实现三维虚拟样机的自动化生成。(4)提出了一种基于美学特征的参数化产品外形设计方法。该方法运用形态控制参数表达产品的形态要素，通过改变形态控制参数，实现形态要素的放大、缩小、变形及组合，从而可获得不同外观创意设计效果的产品外形。文中以工业缝纫机外形设计为例，基于UG平台及其二次开发技术UG／OPEN API，实现了工业缝纫机的外形美学设计，证明了该方法的可行性。(5)提出了一种含外形容器约束的复杂机械系统自动化空间布局方法。该方法将布局容器区分为凸面体和凹面体两种类型。针对布局容器的凹凸性，给出了两种不同的干涉检验方法。文中采用自适应遗传算法实现复杂机械系统的空间布局优化，初始种群可随机产生也可通过人机交互方式产生，人机交互方式用来控制机构组合中起始机构在全局坐标系中的摆放位置及姿态，从而可尽快生成初始种群。基于布局优化结果，采用“后台预置”装配技术，实现对应机械系统在布局容器内的自动虚拟装配。本文的主要特色及创新点如下：(1)将布局设计引入到基于三维设计平台的产品快速创新设计理论体系当中，并基于前期工作，实现了含约束复杂机械系统的自动化空间布局，从而使得由基本机构组成的复杂机械系统既可满足产品的工业美学设计要求，又可满足产品的寿命和可靠性要求。(2)完成了基于三维设计平台快速创新设计理论体系中虚拟样机的自动生成模块。从而使得在三维虚拟样机的层面上，从众多的创成设计方案中快速遴选出最具有创新性的设计方案成为可能。(3)提出了基于美学特征的产品参数化外型设计方法。该方法将美学形态要素与模型的关键特征参数建立关联，通过修改模型关键特征参数，可生成不同的具有创新性的产品外形。更多还原

【Abstract】 The product’s fast and automatic creative design lays the basis for the enterprise to complete with others in the worldwide market. So our research group presented a fast creative design theory system which is based on 3D design platform. Among this design theory system the modules such as automatic generation of symbol schemes, automatic identification of symbol scheme and library of various basic mechanisms have been finished in the early stage. Based on the above works, this dissertation mainly studied on the other modules of the design theory system such as automatic spatial layout of complex mechanical systems with constraints, automatic virtual assembly, and product’s aesthetic design. The main works are given as follows:(1) The layout expression method including connecting relation and space position of basic mechanisms is given for complex mechanical system. Firstly, the connecting relation of basic mechanisms composing mechanical system is analyzed, and the layout models for three types connecting relations are built. In order to facilitate the space expression of basic mechanism, block-based layout model is built according to different cases of basic mechanism’s input and output shaft. Secondly, based on the block-based layout model, the layout space determination method for different basic mechanism such as gear mechanism, cam basic mechanism, link mechanism and groove mechanism are given, and the automatic generation of layout parameters is realized by programming.(2) The automatic spatial layout optimization algorithm for complex mechanical system matching with the identification result of symbol scheme is presented. The math model for layout optimization is built firstly. Then using self-adaptive genetic algorithm, considering the interference status, connecting relation, direction constraint and angle constraint, the fitness function is constructed. By coding each mechanism with four integer number in given scope, the complex mechanism system is denoted with genetic code. By generating the legal population, selection, crossover and mutation with given generations, the layout optimization result of complex mechanism system is obtained at last.(3) Using object oriented method and secondary development environment of 3D platform, the automatic virtual assembly for the mechanical system matching with the symbol scheme is realized. The transform matrix of each basic mechanism stored in the stage of spatial layout is acquired firstly. Then according to the difference between basic mechanism’s layout coordinate system and its modeling coordinate system, the above transform matrix need to be revised to make these two coordinate system same. At last, adopting the predefined assembly technology, every basic mechanism will be positioned at specific location by using the transform matrix data, and 3D automatic virtual assembly matching with symbol scheme is realized.(4) A kind of parametric-based industrial aesthetic design of product is presented in this dissertation. The appearance of product mainly depends on some key aesthetic factors, such as dimensions, ratios and so on. These factors can be taken as control parameters to model the appearance of product. In this dissertation, taking the industrial sewing machine as an example, based on UG platform and secondary development technology (UG/OPEN API), the aesthetic design of industrial sewing machine is realized. The results of the example demonstrate the validity of the proposed method.(5) An automatic spatial layout algorithm for complex mechanical systems with container constraint is proposed in this dissertation. The layout container is classified into two categories: convex and concave. Self-adaptive genetic algorithm is adopted to optimize mechanical systems with container constraint. In this algorithm, each basic mechanism is denoted with four integer genetic code. Human and machine interaction technique is adopted to control the location and orientation of the first basic mechanism. Two kinds of interference test methods are presented for different type of layout container. At last, based on the layout optimization results, adopting predefined assembly technique, automatic virtual assembly for the mechanical system within the layout container is realized.The innovations and distinctions of this dissertation are given as follows:(1) Automatic spatial layout design of complex mechanical systems with constraints is applied into product’s fast creative design theory system, which makes mechanical system not only satisfy the industrial aesthetic design but also satisfy the requirement of long life and high reliability.(2) As an important module of fast creative design theory system, the 3D automatic virtual assembly matching with symbol schemes is realized, which make it possible to select the best creative design scheme from many design schemes by intuitionistic way.(3) A Parametric-based industrial aesthetic design method is presented. This method correlates product’s aesthetic form factors and the key feature parameters of product model. By changing the key feature parameter, different style of product appearance will be generated.更多还原