Research On Robustness Of Sheet Metal Deformation And Assembly Variation Using Response Window And Taguchi Method

Auto-Body is usually composed of hundreds of pieces of sheet metal. Auto-Bodyassembly is very complex, form parts, components, sub-assemblies, assemblies toBIW assembly in multi-station. There are about70-120welding assembly station,each assembly station equipped with a certain number of positioning blocks, clamps,welding torch. Because the assembly relationship is so complex, the auto-bodydimensional variation is inevitable, and they will accumulate, transfer, and ultimatelyhave an impact on the overall quality of the body (performance, visual quality),thereby affecting the competitiveness in the market. So vehicle companies pay a highattention on it. Previous sheet quality control is mainly constructed with sensitivecoefficient matrix and influence coefficient method, then optimize the position of theanchor point by influence coefficient method. Although this method is slightlyimproved quality of the sheet metal, but not hi gh versatility and efficiency, each sheetrequires a repetitive modeling, optimization and control strategy mostly involves onlythe number and position of the anchor point, not involving other control parameters.In response to these problems, this paper proposes a new means to research onrobustness of sheet metal deformation using response window. and in order to studythe robustness of the assembly model, validate the response of a single sheetdeformation useful to assembly model, we do more research o n the assemblydeviation analysis model and Taguchi robustness analysis process, the main contentsare as follows:⑴Proposes a new means to research on robustness of sheet metal deformationusing response window. The control factors are the number and position of thelocating points, the size and area of the extend force.Through DOE and finite elementsimulation, the effective deformation and response window in all levels was obtained.The goal control strategy can be obtained by analyzing the above data. The exampleindicated that the analysis method can successfully analyze and solve the problem ofthe robustness of sheet metal deformation when considering noise factors. So, themethod provided an important and significant idea to reduce the deformation andimprove the robustness of sheet metal.⑵Establish assembly variation analysis model based on influence coefficientmethod, considering parts dimensional variations,fixtures variations, and the fixture variation’s impact on the welding process and its impact on the final assemblydimensional variations. Obtaining the matrix which contains the relationship betweenparts dimensional variations, fixtures variations and assembly variations. As long asyou can get parts variations and fixture variations, you can analysis the statisticalinformation of assembly variations.⑶Combine the assembly deviation analysis model with Taguchi robustnessanalysis process. Compare the design results with the robustness anchor positionobtained by response window method. Then we find the results of the two methods areconsistent. But we can’t directly apply the results obtained by response windowmethod into the robust design of the assembly, we need do more research on assemblymodel by response window method for More accurate range。...