文档介绍：Research on geometry innovative designfor product based on NURBS curve technology A Dissertation Submitted for the Degree of Master Candidate:Song Mingyan Supervisor:Prof. Zhang Weishe Eng. Zhang Tianqi Chang’an University, Xi’an, China 万方数据万方数据 i 摘要产品设计不仅包括功能设计,还包括外观造型设计。对于任何一件产品要想吸引消费者都必须依赖一定的形态,它是传达产品信息的首要因素,也是产品内部结构、内在蕴意等转化为外在因素的关键。因此,几何形态创新设计方法与技术一直是产品外观造型设计领域的关键问题之一。文中介绍了应用Coreldraw、PS、图像轮廓提取、MATLAB等软件的图像处理技术对造型件图像(照片)几何特征提取技术,以及应用Pro/E软件对造型件三维扫描数模几何特征提取技术。以电动车前罩壳为例,阐述了应用NURBS曲线曲面表示产品造型件几何形态的方法与技术,包括型值点、控制点、节点矢量参数等的获取与计算方法与过程。总结了产品造型件功能相同或相近时,其几何形态的NURBS曲线曲面统一表达方法。集成Microsoft Access、MATLAB、ODBC等数字化工具与技术构建了产品外观造型件几何形态信息管理系统,对造型件几何形态的NURBS曲线曲面参数信息进行存取管理,应用MATLAB软件对造型件外形进行仿真呈现;结合MATLAB、BP神经网络与GA,构建了产品外观造型件几何形态创新设计系统,该系统能在案例的基础上, 结合设计师的创意,优化出用户满意度更高的造型件形态方案。以电动车前罩壳为例对造型件几何形态创新设计系统进行应用说明。对造型件几何特征与产品整体几何特征的关系进行了研究,说明了造型件几何形态优化方案与产品整体外观造型的匹配方法。关键词:几何形态特征,NURBS曲线,BP网络,遗传优化,造型创新设计万方数据 ii Abstract Product design considersnot only the function , but also the art of factors .In order to attractsconsumers,any one productmust rely on certain shape, because it is the primary factor of product information, In addition,it also the key that the product structure, internal informationinto external , geometry innovative design method and technology has always been one of the key issues inthe field of product appearance modelling ,thispaper introducedhow to use coreldraw, Photoshop, image contour extraction softwareandMATLAB to get featureline from case pictures,and how to use PRO/E software to get geometric characteristic lines fromthree-dimensional ,this paper take the Electric car coverfor exampleto exploredthe application of NURBS curve and surface in product modeling geometryexpression. Includingthe methodof obtaindata points, control points,node vector parameterand the calculation method and addition,this paper also summarized the unified expression methodof us