Exploration Of CAD For Mechanical Creative Design

This dissertation reviews the art state of CAD, and analyses the achievements and limits of current CAD available for mechanical creative design. Based on characteristics of mechanical creative design and creative thinking pattern, the thinking recognition of mechanical creative design is studied, mechanical creative design model based on thinking pattern is proposed, and the method and way of CAD for mechanical creative design are discussed. According to mechanical creative design model above, CAD for mechanical creative design is explored in a systematic way on the basis of the thinking recognition of mechanical creative design: ? The features and effects of requirement identification in mechanical creative design are studied, and the representation of design requirement is presented. ? The purpose of mechanical function design is discussed, function design process is divided into function identification and function abstract, and a method for function taxonomy as well as function representation is suggested. Also function design model based on function taxonomy and function design method based on legend and guide are proposed. ? Based on function-behavior-structure model, the representation of behavior and principle is studied, and behavior model is founded. Concept design is divided into function logic formation, principle scheme exploration and design scheme implementation, and combination-based function logic formation, analogy-based principle scheme exploration and combination-based design scheme implementation are presented. ? Based on the needs of mechanical creative design, characteristics of structure abstract and evolution are analysed, and logic-based conceptual structure model is presented. Also the method of structure evolution is discussed. ? Based on geometric model variant, the features of constraint-based parametric design are analysed. The relation between extended Euler operator and geometric constraint is discussed on the basis of cell complex, dependency between topology and geometric constraint is introduced, and topology-based geometric reasoning is presented. Also face-based feature original shape is introduced, feature semantic- based feature modeling is suggested. ? The requirements of design evaluation and features of design evaluation model are discussed, the mathematical model and framework of design evaluation based on data fusion are developed. ? Based on union of mechanical design systematic way and computer supporting formalism, component-based CAD model is proposed, and the way for research and tactics for implementation are discussed. Also a prototype is developed. III _ __ This dissertation studies on the way for research and tactics for implementation and establishes a framework available.