Interpreting three-dimensional structural topology optimization results

Abstract

Topology optimization result is usually a gray level image in discrete finite elements, which is hard to interpret from a design point of view. It is especially difficult to interpret three-dimensional topology optimization result. Although there are many techniques for interpreting topology optimization results, most of them only deal with two-dimensional problems, and some of the interpreting techniques must be performed manually. This paper presents an automated process for interpreting three-dimensional topology optimization result into a smooth CAD representation. A tuning process is employed before the interpretation process to improve the quality of the topology optimization result. In the tuning process, a continuity analysis is first used to transform the porous topology formed by the elements with intermediate densities in the topology optimization result into clear 0–1 elements. Next, trivial solids and trivial voids, which are useless in mechanics but will complicate the implementation of the interpretation process, are filtered out. After the tuning process, the three-dimensional structure is divided into representative cross-sections. On each cross-section, a density redistribution algorithm transfers the black-and-white finite element topology optimization result into a smooth density contour represented by B-spline curves on each cross-section. A three-dimensional CAD model is obtained by sweeping through these cross-sections.