Monte Carlo simulation of tolerancing in discrete parts manufacturing and assembly

Abstract

The assembly of discrete parts is strongly affected by imprecise components, imperfect fixtures and tools, and inexact measurements. It is often necessary to design higher precision into the manufacturing and assembly process than is functionally needed in the final product. Production engineers must trade off between alternative ways of selecting individual tolerances in order to achieve minimum cost while preserving product integrity. This paper describes a comprehensive Monte Carlo method for systematically analysing the stochastic implications of tolerancing and related forms of imprecision. The method is illustrated by four examples, one of which is chosen from the field of assembly by computer controlled manipulators.