The Optimization And Allocation Research About Welding Point Of Side Of Car-Body-in-white

The welding quality of the car-body in white have the decisive affection to the quality of the car, in the anciently layout process ,the experience of the layout Engineer decided what is wrong or right, but when the whole Layout process was finished, it would be very difficult to very the result. With the quickly development of the computer technology, especially in the field of CAD, the contemporary Engineer can do the layout work in computer without operation in real working procedure, so the layout cost and the time can be saved greatly. For the whole working procedure have been simulated in the computer, all the connotative error can be fund and amended in time, to avoid taking the problem to the working procedure, decreasing the connotative losing.The welding point allocation task which is mentioned in this article is one of the important portions of the Layout, and it also is the basis of the procedure Layout and the optimization of the Robot route. In this article ,the manufacturing procedure of body side in white is analyzed, and the interrelated factor mentioned in welding allocation are discussed step by step. Based on the analysis, the article present the allocation plan, firstly, the allocation problem can be abstracted into a Multi Knapsack Problem, and the Genetic Algorithm will be selected for solving the Multi Knapsack Problem, the welding Robot can be considered as Knapsack, and the welding Point can be considered as resources which should be allocated, the value of welding point embodied as the distance between the welding Robot and the welding Point, the longer one has the lower value. The result of the Genetic Algorithm can be looked as the result of the welding point allocation. Secondly ,all the factors who have ignored in the first process will be utilized as restriction characteristics to verify the result which is got in the first process, than the final result can be gained. At the same time the welding point allocation software have been programmed.This article have achieved using the math method to describe the welding point allocation process which was used to be decided by the experience of the Layout Engineer, and have programmed the software ,enhanced the efficiency of the layout process, and provided the foundation of the simulation and the optimization of the car-body side in white.Based on the summarizing of software developed process, aiming at the limitation of this article, the set-work and the prospect are expounded.