【作者】 龙昭宇；

【导师】 于多年；

【作者基本信息】 吉林大学 ， 车身工程， 2008， 硕士

【摘要】 计算机辅助设计是从2D绘图开始的。最初,图形元素完全由线段、圆、圆弧构成,而且是静止不动的。后来,在3D线框模型、曲面模型及实体模型发展的同时,参数设计的观念开始逐步形成。它的初衷是用尺寸来驱动图形的改变,即当尺寸更改时相对应的图形元素亦随之变动。如果把每一个结构设计参数的设计原理、准则、规范和设计师的经验等知识都结合在CAD系统中或生成的CAD模型中,使设计人员只要输入设计目标的工程参数和应用要求,智能化的CAD系统就能依据相关的知识,自动得出符合要求的数字化几何模型,由此提出了知识工程。而将参数化设计与知识工程两者有机的结合起来,实现智能化设计,将大大提高设计效率,缩短产品开发周期。汽车内部布置是一个从构思、设计、实验到生产的复杂系统工程,布置时要考虑众多的约束关系和人机工程的要求。同时,汽车内布置设计是一个多方案设计过程和再设计过程。在初始设计阶段,设计师在进行方案构思时,常常需要很多的经验进行判断和选择。而许多布置技术都是建立在原有布置技术基础上,参考类似车型的设计,以满足新的变化了的功能或性能要求。如果能够利用CATIA V5中的知识工程模块进行知识驱动的参数化汽车内部布置设计,将可以大大提高设计效率及质量,缩短设计周期。本文就是基于CATIA V5的知识工程模块,对车身总布置设计工具及汽车内部布置进行初步研究和探讨。更多还原

【Abstract】 Parameterization Design that is drived by dimension and character is used to design product by single geometry restriction and certain function expression. For different auto body, partial configuration and accessories may be various, but the vehicle body is almost similar. Based on this condition, auto body parameterization design is very practicably and necessarily.Traditional parameterization design usually make use of main figuration orientation and assemble dimension of primary design as custom variable. By updating these variables, you can get new design product. But there are some faults as follows: first, custom variable can only drive geometry dimension, it can t drive basic character. Second, custom variables are unattached between each other, it is inconvenient to build function expression and add restriction for every variable. Parameterization design can t be achieved enough.With the development of Knowledge Based on Engineering, new design method of intelligentized design by combining parameterization design and KBE together has been advanced, by which design efficiency will be heightened largely and product exploitation period will be shortened. It is the basic design idea advanced by this article that the Parameterization Design method basing on KBE.This parameterization design method can integrate all information that is related with product design. It contains design standard, related dimension, dimension restriction, related character and technics order. By this intelligentized CAD method, a repository about products could be established. Not only dimension driving and character driving could be realized, but also checkout could be done momentarily by man-machine conversation.Auto interior packaging is the key process in auto design. Based on every assembly type and vehicle performance, we can get auto interior dimension, driver and passenger s hand clearance and interior parts location parameterization to meet vehicle performance and statute requirement. In order to get excellent vehicle packaging, we also need to balance the conflict between every vehicle performance. If engineering designers can make use of parameterization design module to package auto interior, they can avoid heavy repeated workload.As a completed parameterization design software, CATIA V 5 has been applied in every field: aviation, mechanism and auto etc. Its KBE module has been developed in more and more design fields, but the application in auto body layout design is seldom. With strong function about KBE and parameterization modeling, CATIA V5 allow consumer to set up and make use of Standard library freely and unlimitedly. Based on product knowledge, this method is used to build parameter standard modeling by making use of CATIA KBE, then plug standard modeling into CATALOG module to build standard library.The target of this article is to develop the advantage about KBE module attached to CATIA V5 software platform more to achieve the optimization design in auto body so as to ease the task, be convenient to update the dimension repeatedly and save the work time for engineers. This article s study is main about binding the geometry character and dimension parameter together so that realize the automatically update about dimension parameter by substitution of geometry character. Apply CATIA V5 complete parameterization design to set up dimensions connection and dimension drive in order to give dimensions in auto interior packaging checkout and update. As for auto interior design, it is a repeated work to give modification of relevant dimension parameter and relevant geometry elements (line, plane and body). On account of the shortcomings for other software, it is inevitable to use CATIA V5 entirely. KBE is the main component in CATIA V5, it can express strong functionof CATIA V5. CATIA link engineering design and product design, and it make KBE become an important tool. Users can check if the design process can meet technique requirement by defining character, formula and so on. CATIA V5 KBE is including a series of intelligentized software modules like KWA, KWE, PKT, BKT, PEO, PFD and PFO etc. CATIA V5 could denote knowledge by the form of parameter, formulas, rules, check, reports, design table, reactions and generative scripts. CATIA V5 basing on KBE could combine repository of knowledge in the development of products so that could make sure engineers follow the best design practice, development, steps of design as well as improve the efficiency of design.Hand reach is the important design tool of auto interior packaging. If we could make use of principle of parameterization driving to create templet library of hand reach by the function of CATIA V5 KBE module. In this way, in the future design it is convenient for engineer to choose hand reach with different percent and easy to design or check, not only efficiency could be improved but veracity could be increased.Parameterization Design based on KBE make design process become more automatic and reduce design frequency and cost, at the same time, CAD design with experts knowledge and experience can make or change new design proposal automatically and quickly based on requirement. So, parameterization design based on KBE has widely application foreground in auto design area.更多还原