基于语义的轮胎花纹层次化建模方法及其关键技术研究

Based on the thorough research of inherent rules for tire-production design, using the structures of tire tread as the object of study, the project looks for key technologies appropriate for the modeling process of tire-tread-structure design and the representation of production information. The project systematically constucts a computer-aided theory and a method of application for tire tread modeling based on the hierarchical semantic model..The project first studies the hierarchical, completed, and formalized representation of the tire-tread-structure-design-oriented semantic model, confirms the content of customer-demand model, tread-skeleton model, tread-geometry model, and tread-analysis model. The project proposes and realizes the representation of 2D and 3D models of tire tread, the verification of integrity for 3D models of tire tread, and a series of algorithms for 3D-tread-model evolution and drive machanism, thus correlating the process of semantic model's eveolution and the process of tread design as well as the implementation of regularity, systematization, and modeling among demand analysis, concept design, and assembling design..Key scientific problems to be solved in this project is as follow : (1) The different stages of design-oriented digital model of the tire tread will be established. (2) Build a relationship between the tread of digital models and tire characteristics, such as noise, abrasion resistance, water-skiing, rolling resistance, grip, etc. (3) Develop a prototype system of the tire tread design based on the platform of commercial CAD. Using this system to detect and assess the typical tire tread, then apply the results to the design and manufacture of the tire tread..The project leverages object-oriented design approaches, creatively constructs a library for hierarchical tread-semantic modeling and a library of tread-structure design, develops a prototype system of tread design based on the hierarchical semantic model, and applies the research results into the process of structure design for tire tread..The hierarchical modeling approach and its application research for tire tread based on the semantics will contribute for: greatly improving the support for concept design by the CAD techniques and the level of automation and intelligence of production modeling; significantly enhancing the integrity and flexibility of the CAD systems.

以轮胎花纹结构为研究对象，寻求适用于轮胎花纹设计的建模过程与产品信息表示的关键技术，较为系统地建立基于层次化语义模型的计算机辅助轮胎花纹建模理论与应用方法。项目首先研究面向轮胎花纹结构设计语义模型的层次性、完备性和形式化表达方法，确定客户需求模型、花纹骨架模型、花纹几何模型与花纹评估模型内容，提出并实现轮胎花纹2D与3D模型的表达、轮胎3D花纹模型完整性校验、3D花纹模型演进与驱动机制系列算法，把语义模型的演变过程与花纹设计过程结合起来，实现从需求分析、概念设计到装配设计的规律化、系统化、模型化。项目采用面向对象的设计方法创造性地构建层次化花纹语义模型库和花纹结构设计知识库，开发基于层次化语义模型的花纹设计原型系统，并将研究成果应用于轮胎花纹的设计过程中。本项研究有助于极大提高CAD技术对概念设计的支持能力和产品建模工作的自动化、智能化水平，并显著增强CAD系统的完整和灵活性。

以轮胎花纹结构为研究对象，寻求适用于轮胎花纹设计的建模过程与产品信息表示的关键技术，较为系统地建立基于层次化语义模型的计算机辅助轮胎花纹建模理论与应用方法。. (1) 针对以几何特征为主导的建模方式造成轮胎3D花纹模型创建操作繁琐、设计信息表达分散而不完备的问题，提出以语义为主导的3D建模方法。该方法是在花纹设计的应用理论及实用技术探讨和研究的基础上，将理论设计中的花纹沟、装饰品及交汇特征的结构抽象分解得到轮胎花纹语义单元，从而构建花纹语义模型库和结构设计知识库。在此基础上引入轮胎节距信息，实现了轮胎花纹从概念设计到装配设计的层次化、系统化、形式化表达。. (2)针对轮胎逆向建模过程中存在操作繁琐且不规范的问题, 提出了一种基于逆向特征的轮胎花纹层次化建模方法. 该方法是在对轮胎花纹造型特征研究的基础上, 首先将轮胎花纹分解为具有层次性的知识元, 然后按照特征驱动的执行机制驱动点云到不同层次知识元的特征点, 进而驱动特征点到知识元, 并最终实现由知识元到模型的过程.. (3) 为有效地从点云数据中提取吻合轮胎结构设计特征的花纹边界，提出面向胎面点云映射阵的花纹边界提取方法。首先以优化阀值分割获取的胎面点云为对象，将栅格作为基本单元进行3D胎面点云到点云映射阵的转化；然后采用列链码连通性生长的方式获取花纹结构知识单元，构建能够表征花纹结构信息的结构知识库；最后通过求解知识单元相似度实现知识库中花纹的聚类，并借助模式识别实现聚类结果与花纹设计基本类型的匹配，进而驱动基本类型花纹边界特征归类机制实现花纹边界特征点的提取。. (4)针对以人机交互为主导的轮胎花纹工程图尺寸标注造成标注繁多、工作量大及易出错的问题，提出了基于控制点对轮胎花纹工程图实现自动标注及利用排样思想、网格化方法实现对尺寸线的自动布局。该系统在对轮胎花纹的分析及轮胎花纹图元的一系列处理的基础上，自动识别出控制点的剔除及添加，从而实现自动标注。. (5)通过SolidWorks建立十二种花纹轮胎的三维模型，导入ABAQUS中生成有限元模型，然后使用基于ABAQUS CEL方法进行轮胎滑水仿真分析。. 项目采用面向对象的设计方法，开发了基于层次化语义模型的花纹设计原型系统，研究成果被成功应用于轮胎花纹的设计过程中。