Computer-aided robustness analysis for compliant assemblies

Abstract

This paper presents an analysis tool that allows non-rigid parts and assemblies to be evaluated with respect to geometrical robustness. The robustness evaluation aims at detecting design and assembly solutions that are sensitive to variation and may cause problems later on during production. The analysis tool enables the designer to evaluate the geometrical sensitivity of a part or assembly, what the sources of variation are, their importance for the overall robustness and in what order to improve the design. It allows designers and production engineers to evaluate and improve different types of locating, clamping and joining schemes with respect to non-rigid deformation of parts due to part variation and fixture variation. The analysis tool is implemented in a Windows environment and has interfaces to IGES, VRML, STL and ABAQUS, which enables the user to import computer-aided design geometry, finite element meshes and stiffness matrices, and to perform robustness and tolerance analysis for different locating, clamping and joining layouts. The results are presented in stability matrices, as sensitivity factors and with colour-coding of the sensitivity of the geometry.