【作者】 祖耀；

【导师】 肖人彬；

【作者基本信息】 华中科技大学 ， 机械设计及理论， 2009， 博士

【摘要】 产品设计的根本目的就是要创新产品，以满足客户需求和占领更大的国内外市场。产品的功能是客户对产品的最本质要求，更是决定客户购买产品的关键因素之一。因此研究和实现产品功能是产品概念设计的核心问题，对提高产品设计的创新性及高效性，缩短产品开发周期，降低成本和增强市场竞争力，具有非常重要的理论意义和现实意义。本文在借鉴国内外相关研究成果的基础上，以机械产品的功能特征和机械产品概念设计方法为重点研究对象，将新型计算智能方法与创新设计理论引入其中，探讨机械产品的功能特征与机械产品概念设计之间的关系，为机械产品概念设计提供一种新的研究途径。首先，详细分析了功能在产品设计过程中的重要作用，产品设计由功能引导，研究功能特征驱动、制约和构成产品概念设计过程，阐述了功能特征驱动的机械产品概念设计原理；由此建立起一种具有迭代特性的机械产品概念设计模型，并对其进行了形式化描述，并研究机械产品的功能、行为、机构和结构之间的关系、机构建库与功能推理方法和机制，采用重新定义设计问题和部分概念解的迭代设计方法，寻找满足产品功能需求问题的最佳解。然后，根据组成机械产品的机构，其输入和输出的基本运动功能特征具有确定性和可推理性等特性，研究其形式化描述方法，提出了一种基于枚举和功能推理的机械产品传动系统概念设计自动化方法。该方法采用分类方法来定性地描述机构及机械系统的基本运动功能特征，采用数据库技术和代码符号，由枚举算法计算出每个机构的可连接的接口条件，通过功能推理和枚举运算来自动生成众多的满足机械传动系统设计要求的机构组合方案。随后，针对机械产品的功能本身具有复杂性、层次性和多样性等特点，从而有利于拓展机械产品的概念解，于是根据这个思路，提出一种基于变功能参数的机械产品创新设计方法。在对机械系统组成进行分析的基础上，建立了功能特征扩展和功能参数知识库模型，运用变功能参数操作，实现了产品功能的组合、变异和扩展，并使得产品结构相应的发生改变和重构，从而达到产品创新设计的目的。此外，本文还对功能特征驱动的机械产品造型设计方法进行了研究。基于产品的结构和外形服务于功能，以及功能决定产品结构和外形的指导思想，将产品外形造型设计看成功能特征到外形的映射，然后利用功能特征分类、提取、参数化和形式化描述，建立了产品的功能特征和结构外形之间的关系模型，通过分析产品功能特征和外形之间的对应关系，建立了产品功能特征和外形共进化设计模型及其算法，经过产品功能特征和外形的共进化过程，实现计算机辅助产品造型创新设计，为产品外形造型设计提供了一种新思路和方法。最后，基于上述理论方法研究成果，研制了功能特征驱动的机械产品概念设计原型系统，并通过蜂窝煤机设计实例验证了其可行性和有效性。更多还原

【Abstract】 Product design method and creative design play an essential role in product development, and effective product design can determine the product performance, directly affect the consumer and increase market share. The central objective of conceptual design is to generate physical descriptions of designs, sufficient for their implementation, which would provide the intended function to users’ satisfaction. Therefore, the investigation into how the knowledge of functionality can be used to improve quality, reduce cost, and reduce time to market, is very important for present conceptual design research of mechanical products.Using the relevant theoretical research achievements for reference, the functional feature and conceptual design theory of mechanical product are deeply researched in this dissertation, in which new methods of computational intelligence and creative design theory are introduced. The relation between functional features and conceptual design is discussed, and a new approach to the theoretical research on conceptual design and creative design of mechanical product is presented.Firstly, designing should be guided by functions. In other words, the knowledge of functionality can be used to guide, constrain and shape the design activity, which is an important strand of present design research. Then an iteration-based function-behavior-mechanisms-structure (FBMS) model is proposed. the generation of problem solutions satisfying function requirement is supported by the model, in which the strategy of hierarchy in relative to the function and the mechanisms of building and transferring component base are produced, as well as the methods of recursive problem and solution redefinition are adopted.Secondly, an automated method for conceptual design of mechanisms using enumeration and functional reasoning is presented. Based on principle of combination and categories of functions, design requirements and building blocks are expressed by function codes, an enumeration process is proposed to enumerate all possible and feasible functional connections of each building block in the knowledge base. Then a new combinatorial algorithm is computerized to automatically yield many candidate solutions to the desired function requirements using bidirectional search, and functional reasoning is introduced to filter out infeasible solutions.Thirdly, product design is considered as functional satisfaction problem, and an innovative approach of mechanical product design using function parameter mutation operation is presented. In view of the complexity of the function of mechanical products, the functional characteristic model and the knowledge library of function parameters were established. Through the function parameter mutation operation, then function and structure of products were modified and generated. The design processes can be used to obtain a variety of innovative products.Finally, configuration design is also studied in this dissertation. Directed by the idea of the function of product determining the structure, and also based on the description of mapping from functional domain to configuration domain, a new method for creative configuration design of product using functional feature is established. Then functional requirements and design parameters are classified and formalized in terms of characteristics set, and after constructing the mathematical model of searching for the possible combinatorial solution, a general co-evolutionary algorithm is introduced to automately generate a lot of creative configuration of product, which is according to the accordant relation between structure and function.Using the above methods, a prototype system for computer-aided conceptual design of mechanical products is developed, and by means of which the design of honeycomb briquette machine is successfully accomplished. The case study indicates that the proposed methods are feasible and effective.更多还原