Modular Design Theory And Its Application In The Design Of The Bridge Crane

With the globalization of economic development and China's entering into WTO, the competition in domestic mechanical market is becoming increasingly severe. In order to keep company's advantage in the competition, we must enforce innovative capability, shorten design cycle and increase degree of customization. At the same time, we have to reduce cost, maintain quality of product and good after-service. Traditional method of designing cannot have met above-mentioned needs. Modular design turns mass production of customized products and individualization of it into realization by module programming and combination. And it can fit the demand of cutthroat competition of market. On the basis of current modular design theory, a full modular design method is put forward in this thesis aiming at all design procedures in the development of new product.It is the final intention of developing new products to meet the needs of customers. In this thesis, the programming of product line is analyzed from the point of view of modularization and the theory of modular design is studied in detail. First the main customer group and their expectation to the new product is confirmed by the market research and analysis of similarity product in the market. Then, the main function of new product is decomposed into small functional model by the method of function decomposition. On the basis of these, the relativity of functional models is analyzed and quantified. And functional models are reassembled by the method of fuzzy clustering analysis. Thus, a series of programming plans are obtained. Using entropy, a best programming plan can be selected by the evaluation of design, manufacture, assemble and maintain and so on. Finally, a product platform can be set up by analysis of influence degree of the functional modules to customer command. The storage format of a functional model and the structure of functional model database are also been studied in this thesis. The function of model is set as the keyword of functional model database. A model-selecting algorithm based on fuzzy pattern recognition is brought forward here. The validity and usability of the modular design method presented in this thesis is verified by the example of overhead traveling crane.This study supplements the theory of modular design. And the design process and integrated design content are presented here, which is a promotion to the modular design technology using in mechanical product development.