【作者】 徐敬华；

【导师】 张树有；

【作者基本信息】 浙江大学 ， 机械设计及理论， 2009， 博士

【摘要】 当今世界,科技进步日新月异,市场竞争日趋激烈。经济全球化步伐加快,产品的研发周期缩短,客户需求日趋多元化,制造企业处在一个动态多变的市场与生产环境中,设计创新势在必行。在产品设计过程中,随着设计因素的变化和设计深度的增加,产品过程模型及关联知识在复杂度和数量上都急剧增长,而此类时变资源却难以在目前的CAD系统中得到重用和共享,造成隐含在设计过程中的知识大量流失,为此,提出了面向变异设计的移植单元检索与融合过程进化技术。将设计因素变化的设计定义为变异设计,根据设计对象、设计目标和设计尺度的变化将变异设计分为三类:结构变异设计、目标变异设计和尺度变异设计。通过构建三维模型的检索索引,快速定位相似模型,实现面向结构变异设计的移植单元检索。通过融合贯穿设计过程的资源、规则、知识等因素,使设计朝更优的方向发展,实现融合过程进化。变异设计中的进化技术,在设计因素变化和设计深度增加中推进设计正向演化,显著提高设计效率和质量,体现了当代设计的高级需求。本文研究工作围绕五个方面展开:三维模型形状相似性检索;贯穿过程的设计片段重用;融合过程的时变知识获取;复杂多目标的表达与求解;微米尺度的产品设计建模。取得五项创新:发展了三维模型形状相似性检索技术,实现了以节点资源重用为显著特征的进化设计;发展了贯穿过程的设计建模与重用技术,实现了以过程片段重用为显著特征的进化设计;发展了融合过程的知识获取及其主动导航技术,实现了以时变知识融合为显著特征的进化设计;发展了面向目标变异的空间机构优化设计技术,实现了以复杂多目标的表达与智能计算为显著特征的进化设计;发展了面向尺度变异的微米产品柔性设计技术,实现了微观尺度中以柔性设计流为显著特征的进化设计。本文的组织结构为:第一章,阐述了面向变异设计的移植单元检索与融合过程进化技术,综述了国内外相关研究及应用的现状,指出目前产品数字化设计研究的不足,介绍了研究内容和论文结构。第二章,提出并实现了面向结构变异的移植单元检索技术。发展了基于形态分布图与BP神经网络的三维模型检索方法,将现有的形状线性索引拓展到具有更强描述能力的非线性索引,实现了基于递归分割的机械零件三维形状结构检索。第三章,提出并实现了面向结构变异的产品设计过程重用技术。发展了基于关联与回溯的产品变异设计过程重用方法,该方法将设计重用对象由静态的孤立设计节点拓展到动态的连续的设计过程。第四章,提出并实现了面向结构变异的时变知识获取与主动导航技术。发展了融合产品变异设计过程的知识颗粒获取与主动导航方法,该方法将动态导航的决策依据由静态的孤立设计状态拓展到动态的连续设计过程,可更柔性地适应于不同的设计者和结构变异设计的不同阶段。第五章,提出并实现了面向目标变异的操作臂运动学优化设计技术。发展了面向可辨轨迹的操作臂运动学优化设计方法,将现有基于轨迹的尺寸综合拓展到基于轨迹和运动学的多目标设计。第六章,提出并实现了面向尺度变异的微米产品柔性设计技术。发展了基于Petri网的MEMS柔性设计建模方法,该方法将现有MEMS设计从自顶向下和自底向上及其混合拓展到基于Petri网的柔性设计建模,使产品设计不局限于固定的设计流程。第七章,介绍了面向变异设计的移植单元检索与融合过程进化平台。在自主原型系统中,以多种复杂机械产品作为应用实例。第八章,总结了本文的研究成果,并指出了今后研究工作的方向。更多还原

【Abstract】 Nowadays, scientific and technological progress is changing quickly and market competition is becoming fiercer. Design innovation is imperative in view of current situations: the step of economic globalization speeds up; the product development cycle shortens; the customer requirements become more diversified; manufacturing enterprises are in a dynamic changing environment of market and production. During the design process, with the change of design factors and increase of design depth, the product process models and associated knowledge are increased considerably in complexity and quantity. However, this kind of time-varying resource is difficult to be reused and shared in present CAD systems which leads to the huge drain of the knowledge hidden in design process. Therefore, variation design oriented technology of transplantation element retrieval and fusion process evolution is put forward. The design whose factors change is defined as variation design. The variation design is classified into three types: structure variation design; object variation design; scale variation design. Structure variation design oriented technology of transplantation element retrieval is realized via constructing shape retrieval index and locating similar models rapidly. Fusion process evolution is realized via fusing the factors such as resource, rules and knowledge throughout the design process and making the design develop towards the better direction. The evolution technology in variation design promotes the design forward with the change of design factors and increase of design depth which improves design efficiency and quality as well as reflects the advanced requirements of modern design.The research works are developed around 5 aspects: shape similarity retrieval of 3D models; design fragment reuse across the process; time-varying knowledge acquisition throughout the process; expressing and solving of complex multi-object; design modeling of micrometer scale product. There are 5 innovations: the technology of shape similarity retrieval of 3D models is developed, the evolution design which takes node resource reuse as remarkable characteristic is realized; the technology of design modeling and reuse across the process is developed, the evolution design which takes design fragment reuse as remarkable characteristic is realized; the technology of acquisition and active navigation of time-varying knowledge throughout the process is developed, the evolution design which takes time-varying knowledge fusion as remarkable characteristic is realized; object variation oriented technology of optimization design of spatial mechanism is developed, the evolution design which takes expressing and intelligent computing of complex multi-object as remarkable characteristic is realized; scale variation oriented technology of flexible design of micrometer product is developed, the evolution design which takes flexible design flow in microscopic scale as remarkable characteristic is realized.The organization structure of full text is as follows:In chapter 1, variation design oriented technology of transplantation element retrieval and fusion process evolution is described. The research and application situation at home and abroad is reviewed. The shortage of present research for product digital design is pointed out. The research content and architecture of the dissertation is introduced.In chapter 2, structure variation design oriented technology of transplantation element retrieval is presented and realized. The shape retrieval method of 3D models based on shape distribution graph and BP neural network is developed. The present shape linear index is extended to nonlinear index. A 3D shape and structure retrieval method of mechanical parts based on recursive segmentation is realized.In chapter 3, structure variation design oriented technology of product design process reuse is presented and realized. A process reuse method of product variation design based on association and backtracking is developed. The design reuse objects are extended from the static isolated design node to the dynamic continuous design process.In chapter 4, structure variation design oriented technology of acquisition and active navigation of time-varying knowledge is presented and realized. A method of acquisition and active navigation of knowledge particles throughout product variation design process is developed. The navigation decision basis is extended from static isolated design status to dynamic continuous design process so that it more flexibly adapts to the different designers and various structure variation design steps.In chapter 5, object variation design oriented technology of kinematics optimization design of manipulator is presented and realized. Discernible trajectory oriented kinematics optimization design method for manipulator is developed. The present trajectory based dimension synthesis is extended to trajectory and kinematics based multiobjective optimization design.In chapter 6, scale variation oriented technology of flexible design of micrometer product is presented and realized. A flexible design modeling methodology for MEMS based on Petri Net is developed. The present design methods are extended from top-down, bottom-up and hybrid to flexible design based on Petri Net. The product design is no longer restricted to fixed process.In chapter 7, the platform of variation design oriented technology of transplantation element retrieval and fusion process evolution is introduced. In independent prototype system, the various complex mechanical products are taken as examples.In chapter 8, the research results of this dissertation are summarized and the ways for further research are pointed out.更多还原