| In order to solve the problems of structural expression, structural conception and design process description in conceptual design automation, the paper systemly outlined the present research situations of modern design theories, design methods, conceptual design and TRIZ (Theory of the Solution of Inventive Problems) at home and abroad, gave a detailed analysis of the research results on related fields and their development trends; Based on theory of Function Surface decomposition and reconstitution design automation, TRIZ scientific effect tool was adopted, and effect modeling was established after deep research, based on which the key technologies to achieve conceptual design automation were developed. The study are of great theoretical value and far-reaching economic value in improving the ability to understand and master the man-made products, which will help the development of conceptual design automation theory, and beneficial to product knowledge and structure data automatic processing. The main contents and progresses are as follows:Considering the problems of fluid positioning and fluid functional modeling in conceptual design, on the base of Generalized Positioning Principle, Vessel Principle was put forward, and Energy Blocking Surface was added to the Function Surface information modeling; In order to solve the mapping problems of "fluid positioning function - structure", Vessel Surface was put forward. Vessel Surface is different from Make General-Location Surface for it is fluid oriented and must form an airtightness surface group with feature of qualitive continuity. According to design automation, a series of Vessel Patterns were put forward and their coding rules were designed, and it was pointed out that product conceptual design in which fluid was the main operation target is the design of vessel that supports function transfering.In order to solve the mapping problems of "effect - structure" well, and enrich conceptual design automation theory further, using TRIZ effect tool for reference, Effect Surface was put forward against the stage of effect to structure mapping and served as conceptual design modeling, thus achieved improved "function - effect - Effect Surface - structure" mapping process model. For design automation and reuse of scientific principles and structure instances, instance effect, Effects Pattern and Effects Pattern chain were put forward, and were applied and managed through Effects Pattern library method. Generalized Positioning Priciple and Vessel Priciple were taken as operable effects, and positioning was used to express their inputs and outputs. The library unified existing Generalized Positioning Pattern, Vessel Pattern and other type of Effects Patterns that were established on the basis of the former two, and developed the function of "create follow-up chain", "create control chain" and "create Effects Pattern chain" to speed up the design process. Therefore, With the help of the library, using Effect Surface to build the initial product conceptual prototype, following principle of D & R and 'Three Flows in One' thinking, through coupling between Effect Surfaces of the two Effects Patterns which have effect link relationship, by transferring the main flow, adopting Simultaneous Link Reasoning method, effects chain principle solution and conceptual structure solution for main flow transmission were gradually gotten, so that based on results of successful design, directly and efficiently top-down design process which was constrained by designer was achieved, and made the product initial prototype refined and concretized, then through coding shell parts, separating shell database and entity database to match shell parts, entity mapping of conceptual scheme was easily to come true. While to the management of design solutions, product scheme tree and version management method were adopted, which solved the problems of version querying, version tracking back and version storing, and multi-people, multi-levels and multi-objects fuzzy evaluation method were adopted to handle solutions selection. Therefore, through Effect Surface, "function - structure" rapid and stable mapping was achieved. The function of automatic formation of a complete system model and to accomplish preliminary calculation in growing conceptual design phase were put forward and realized. The formation of energy chain and its preliminary calculation for energy-based products were mainly studied. During reconstitution of design process through synchronous link reasoning, energy output and energy input cohesion which helps achieving energy flow transmission was taken as a major consideration, and three flows in one idea was adopted to the other flow's reconstitution, then structure and energy chain synchronization realization was achieved. Furthermore, through setting the main parameters and control parameters data which controlling energy flow transfer, by means of Effect Surface to save the data, and through the cohesion of the main input parameters and output parameters of effect formula, formula iterative calculation which support energy chain calculation was come true, so that early stage data support can be gotten. Moreover, through changing control parameters, main parameters and structure revise can be gotten quickly accordingly.Based on the above design theories and key technologies, using object-oriented technology and on the base of Mechanical Desktop geometric modeling platform, taking ObjectARX, Access database, and Visual C++ as the main programming environment, computer-aided conceptual design system -ES-DARFAD was developed. Therefore, integration of design theories and CAD software, visualized design process and friendly user interface were achieved, and detailed design stage transition was come true.The design process of ES-DARFAD was illustrated by a case of water heater design, which proved the feasibility of the theories researched. The study is an important reference and guidance to the research and development of computer-aided product conceptual design automation system.
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