A computer model for time-based tolerance design with response surface methodology

The Response Surface Methodology (RSM) approach is adapted to data analysis for computer simulation to determine the optimal component tolerance in an assembly. RSM is a combination of mathematical and statistical techniques, which provides designers not only with optimal values but also with the critical components of an assembly design. These two properties provide designers with guidelines, feedback, and suggestions during the design processes. Since the relevant quality characteristics in an assembly are systematically shifted as the customer using time increases, due to the wear process in some components, a time-based tolerance analysis should be included for assembly design. In this study, the response values for measuring relevant quality characteristics at various times are the process capability index and the total cost. The total cost consists of quality loss and tolerance cost. Because most of the assembly functions are unknown, difficult to obtain, or need to be changed during the design process, VSA-3D/Pro software is employed to run a computer simulation and convert the computer experimental data into response values. Based on these values, a robust and optimal tolerance design is achieved through RSM analysis. As a result, a tolerance design for quality improvement and cost reduction can be completed in terms of product life cycle.