【作者】 杨化林；

【导师】 吴荣仁； 童水光；

【作者基本信息】 浙江大学 ， 化工过程机械， 2006， 博士

【摘要】 本文以宁波市科技局工业科研攻关项目—“基于知识工程的塑料模具快速设计系统”为背景，以注塑模具为主要研究对象，将知识工程思想、数据库技术、推理技术应用于工程设计，目的在于建立基于统一的产品数据管理环境下的注塑模具辅助设计系统，使得企业设计知识得到最大限度重用。本文研究工作主要有以下几方面：1．针对塑料材料多样性和材料选取的困难性，深入研究了材料数据分类方法以及材料性能与塑件制品的关系，建立了综合性能数据库，包括塑料性能、塑料熔体流动行为、塑料配置与着色等子数据库。根据材料性能对塑件结构的影响，建立了“材料性能—塑件结构要素”映射机制，自动求解塑料性能对塑件结构要素的影响，以及塑件结构要素(功能)所要求的材料性能。研究开发了对材料性能数据库的全局查询导航器，通过关联查询得到与该材料相关的所有信息，并输出为各种格式的数据以备共享。2．塑料制品设计结构对塑件顺利成型、防止产生缺陷从而降低成本和提高设计效率有重要影响。考虑塑料制品的加工工艺性，针对塑件的侧面凹凸、脱模斜度、塑件壁厚、加强筋、孔设计等十余个方面，提供设计方案的支持和检查，以帮助塑件设计者快速设计出结构合理的产品。3．根据注塑模具设计具有强经验弱理论的特点，深入研究了注塑模具基于范例推理的设计方法。在最近邻法基础上提出模具范例的相似度算法，并充分考虑不同历史时段技术发展水平导致的模具设计和加工手段的进步，减小由于庞大的范例库造成的匹配时间复杂度，提出采用过滤机制：首先限定一定的搜索范围，只对此范围内的范例进行相似度计算匹配，从而最大限度的提高系统计算、匹配效率；给出特征权重调整的简洁方法，以对传统最近邻法产生的不精确性进行修正。针对检索到的模具范例，从零部件信息和装配结构两个方面进行调整，提出了基于标准件库的离线式零部件编辑和以“配合关系寄存器”为中间件的结构调整方式。提出了一种设计时范例数据获取与重用的设计过程刻录的在线式范例应用的新方法，为基于范例的自动模具设计开辟新途径。4．研究了注塑模具设计中快速建模技术。利用参数化建模技术，研究了模型参数驱动的零部件设计方法，提出以“单遗传结构”的形式描述零件参数，以多级别数据存储结构为零件参数的存储方式，使得平面二维表格(或者复杂的树状表格)简化为线性数据结构，每条记录成为仅包含参数控制关系的单个参数的数据，从而建立可动态扩充的系列化、标准化的零部件设计系统。提出基于统一装配模型的模架设计技术及特征识别技术，利用冗余控制参数实现模架变型设计的模架装配系统。利用这些方法和技术，提高了模具设计建模自动化能力和总体设计水平，并为企业实现统一的信息管理打下坚实基础。5．建立了基于统一信息管理平台PDM的企业集成设计管理环境。以注塑模具设计为例，讨论了塑料材料性能数据库集成、塑件结构工艺性数据集成、基于CBR的模具设计推理方法集成、模型参数驱动的零部件设计集成以及基于统一装配模型的模架设计集成。分析了企业应用软件工具集成和封装的方法，讨论了基于XML的企业数据传输与共享，PDM与ERP的集成。对于企业数据安全，提出了基于对象／基于规则／基于任务流程／基于项目的综合控制方法，使得统一的产品数据管理平台下的企业数据安全得到有效保障。更多还原

【Abstract】 This paper is based on the Key Industry Research program of the Science and Technology Bureau of Ningbo City, which name is "Knowledge Engineering based Injection Mold Rapid Design System" . To design plastic injection mold, the idea of knowledge engineering and database reasoning technology are applied. The main target is to establish a rapid design system for injection mold under the uniform product data management environment, and to make the best of reusing the design knowledge in the company scale. The main tasks of research are as following:1. Under the circumstances of plastic material’s diversity and the difficulty of material selection, the material data classification method and the relation of material property and the plastic part are studied, and the general database which including material property, melt plastic flow behavior, plastic configuration and pigmentation libraries is set up. "Material property -plastic structure factor" mapping mechanism is created according to the material property influence on the plastic product. The mapping tool can automatically solve the mutual influence and requirement between material property and plastic structure factor. The general inquiry navigator is developed to search the associated information of the material selected, and export the selected information to several formats for share. The results indicate that this system can solve the problem of multipurpose plastic material selection fairly well.2. Plastic’s Structure has great impact on the molding process and preventing the product’s disfigurement, and so as to reduce the cost and increase the efficiency. The plastic’s manufacturing process is considered, such as concavo-convex profile, taper, wall thickness, reinforce plate, hole design method, etc. The user can get help when he is designing the plastic, so that he can work out perfect product.3. The injection mold case similarity based on the nearest-neighbor is studied and the dissimilitude is discussed also to exalt the result validity for the case reasoning. To consider the difference of the technology in different period of time, and to reduce the match time complexity when searching the large scale case base, the case filtering mechanism is imported to limit the searching range. Thus only the needed cases are matched and computing efficiency is improved maximally. To adjust the selected case to match the aim, two aspects are offered. The first one is to modify the parts’ information offline based-on the standard parts library; the other one is to adjust theassembly structure by "match relationship register". Finally, a new method of obtaining and reusing the designing cases is given, which the design process is recorded online and reused whenever needed. All these methods help to design mold automatically.4. Rapid modeling technique in plastic mold design process is studied. With the parameterized modeling technique, the modeling-parameter-driven part design method is studied. The single inheritance structure method is proposed to describe the parts parameters, and the multilevel data storage structure is proposed as the way to store the parts parameters, so that the plane 2D table (or complicated tree-like table) is simplified as liner data structure. Each record of this data structure contains only one parameter which includes control relation. So the serial and standardized parts design system is established, which can be dynamically expanded. The uniform assembly mold base design technology is proposed, which can be used to realize mold base change design with the same mold base seed assembly with the help of redundancy control parameters. With the help of all these methods and techniques, the capability of automatic mold design is improved and as a whole the design technology is improved too.5. PLM based integration in enterprise is very important, and it has brought great change in product design and management process. Take the plastic mold design process as the example, plastic material performance database and structure feature data are integrated into the PDM system. Mold design technology such as the CBR, model parameter driven parts library, uniform assembly model, are controlled by the PDM environment. The integration and encapsulation method of many kinds of software tools used in enterprise is analyzed and XML-based data transfer and share is also discussed. The synthesis control methods of enterprise data security are based on rules, objects, workflow and projects, so that all the data are controlled properly in the whole enterprise.更多还原