3D assembly simulation system for parts with geometric deviations

Abstract

Current CAD systems and peripheral software can handle solid models. However, a solid model reflects only one aspect of a component's geometry, that is, its ideal (or nominal) shape. For tolerance analysis, component models should allow geometric deviations. In this paper we propose a deviant component model, which consists of (1) a solid model and (2) deviations of surfaces at selected points. Given such a deviant component model, the relative positions of fitted parts are calculated by using linear programming, which uses an objective function derived from the attachment conditions. Design variables' values and ranges are also estimated.