Ce-cafd System Design And Key Technology Research

The jigs and fixtures system is important to ensure a product satisfying design requirement and to stabilize the product quality. Jig and fixture design is a complex activity that needs extensive information and deep understanding about design, manufacturing, assembly and inspection. With the development of manufacturing technology, more and more flexible manufacturing systems and computer numerical controlled machine centers are used in industry. This causes a strong demand in computer-aided fixture design to shorten manufacturing cycle time and reduce cost.On the basis of analyzing the shortcomings of the current CAFD systems, the system architecture of a concurrent engineering CAFD system has been presented. Secondly, the factors of fixturability of part and evaluation index of fixture are discussed in detail. Owing to the fuzzy characteristic of them, a method which to get the factors and index using fuzzy semantic word to describe evaluation value is presented. And, this thesis presents a way to evaluate the fixturability of part based on BP network. Then, the definitions of valid surface and valid path are given in the thesis, and the fast assembly model is established. And then, based on a method for multi-objective decision-making with partial weight information, the thesis implemented a way to get the best plan of fixture designs. Finally, the CAFD system has been designed and analyzed in detail based on the ICONIX process and the functions and interrelations of the system object classes have been elucidated by Use Case diagram, class diagram, Robustness diagram and sequence diagram.