Statistical Tolerance Analysis Based on Good Point Set and Homogeneous Transform Matrix

Tolerance analysis is increasingly becoming an important tool for mechanical design, process planning, manufacturing and inspection. It provides a quantitative analysis tool for evaluating the effects of manufacturing variations on performance and overall cost of the final assembly. This paper develops a method for statistical tolerance analysis. Firstly, n samples are generated based on the good point set according to the distribution of each dimension. Then, for every sample, one sample of functional requirement can be computed according to the assembly constraint equations. In this paper, the homogeneous transform matrix is introduced to describe the assembly function and Newton-Raphson iterative procedure is adopted to solve the assembly constraint equations after the iterative formula is deduced. Finally, the first four order moments of function requirements can be computed after n samples of function requirements are gotten. A case study is carried out to validate the proposed method at the end of this paper.