Research on Integrated Computer-Aided Design Systems toward Fusion with Engineering Simulation Technologies

本课题研究在各种计算机模拟技术在一般设计活动中成为可能后的下一代集成CAD系统。仿真技术是设计评价不可或缺的手段，但设计本身就是综合活动，必须将仿真技术成果与设计综合活动相结合。在此背景下，本文对对象建模方法、分布式设计系统和优化技术进行了研究。（a）提出了一种以配置为中心的建模框架，该框架具有管理层次化设计信息、推导仿真模型等功能，是实现上述集成的关键技术。该模型也被应用到一个空调机组的设计问题，其中一些组件的安排和多个管道的路由。(b)针对大型复杂系统的并行设计过程，提出了一种基于Agent的分布式设计系统体系结构。该体系结构可以按照工程系统的体系结构，通过计算机网络将孤立的设计系统集成起来。为确定船舶的总体结构，实现了船舶基本设计的实验设计系统。(c)针对实际工程系统的大规模多目标设计问题，提出了一种基于遗传算法的设计优化方法。将该方法应用于某汽车发动机的初步优化设计问题。(d)以链式机构系统的设计问题为研究方向，探讨了概念设计阶段和构型设计阶段的综合集成问题。

This project studied the next-generation integrated CAD systems after various computer simulation technologies have become available in ordinary design activities. While simulation technologies are indispensable for design evaluation, design is natively synthetic activities, and it is necessary to integrate simulation technology outcomes and design synthesis activities. Under this circumstance, we researched into object modeling methods, distributed design systems and optimization techniques. The research results are summarized as follows :(a) A configuration centered modeling framework was proposed as a key technology toward the above integration, which has abilities to manage hierarchical design information, to deduct simulation models and so forth. This modeling was also applied to a design problem of an air-conditioner unit, where some components are arranged and several pipes are routed.(b) An agent-based distributed design system architecture was developed for concurrent design processes of large, complicated systems. This architecture can integrate isolated design systems through computer network in accordance with system structure of engineering systems. An experimental design system was implemented for basic ship design for ascertainment of the architecture.(c) A genetic algorithm based design optimization method was developed for large-scale multi-objective design problems of practical engineering systems, physical phenomena of which are too ill-posed to apply ordinary design optimization methods. This method was applied to the preliminary optimal design problem of an automotive engine.(d) Futher, the issues toward integration of design syntheses in conceptual and configuration phases were discussed with a design problem of chain-type mechanism systems as a forthcoming research direction.