Research on Computer Aided Tolerance Optimization in Aircraft Manufacturing
|School||Nanjing University of Aeronautics and Astronautics|
|Course||Aviation Aerospace Manufacturing Engineering|
|Keywords||Computer Aided Tolerance Design The standardized dimensions coordination relationship Coordination of accuracy Monte Carlo method The mixing tolerance - cost model|
Interchange and coordination center of aircraft manufacturing process planning the reasonable tolerance design is an important guarantee for the interchange and coordination, a direct impact on the quality of aircraft manufacturing, assembly success rate and manufacturing costs. China's aircraft manufacturing industry commonly used the traditional tolerance design means low efficiency, reliability and poor highlight the issue, has been unable to meet the requirements of the development of modern aircraft manufacturing, as a constraint to further enhance the quality of the aircraft manufacturing bottlenecks. In this paper, the development of modern aviation manufacturing technology needs the support of the National Natural Science Foundation of China Postdoctoral Science Foundation of Jiangsu Province, computer-aided aircraft manufacturing tolerance optimization design techniques, research and research results are as follows: combination of aircraft manufacturing process characteristics, based the standardized dimensions coordination relationship defined tolerances representation model. The model integrates the coordination of the size of the structural unit manufacturing process information of the transmission links and tolerance information to achieve a tree structure and the size of the adjacency matrix harmonious relations based computer model designed and implemented with good structural and accuracy characteristics the size of the coordination process documents as tolerance external representation model. Automatic generation algorithm based the standardized dimensions coordination relationship defined manufacturing coordination roadmap. Aircraft the typical components manufacturing coordination accuracy analysis. Summarized into shape two types of coordination and intersection coordination with similar coordination characteristics in aircraft manufacturing to establish the accuracy of the manufacturing coordination model assuming a normal distribution based on tolerance. The the assembly coordination of the calculation of cumulative error and success rate formula is derived based on probabilistic models. Chain analysis techniques based on the size of the Monte Carlo method. Actual production form a ring size presents the characteristics of a variety of probability distributions, the mathematical model of size chain simulation and assembly quality, biconvex peak distribution, triangular distribution, size distribution type random sampling algorithm. The quantitative analysis method based on the performance of the closed loop size distribution of the KS test type automatically determine the the Assembly success rate, contribution rate assembly quality. Tolerance based on the mixing tolerance - cost model to optimize the allocation of technology. Polynomial function of the composition of the ring the tolerance bandwidth and processing method of the relationship of the relative cost of solving the overall size of the chain relative processing costs, as tolerance optimization allocation to minimize cost targets, product assembly requirements as constraints Finally, using genetic algorithm to optimize the composition of the ring tolerances. On the basis of theoretical studies, we developed aircraft manufacturing tolerance allocation decision-making system, the system has been applied in an aviation enterprise, greatly improve the the tolerance design efficiency and correctness.