Automatic Processing and Cross Section Analysis of Topology Optimization Results

Kurzfassung

Finite element-based topology optimizations have become a vital tool in the design of lightweight-optimized components and structures. Used in the early stages of the product development process, they can help identify load paths and shape the fundamental design of a product. However, the interpretation of topology optimization results can be a challenging and time-consuming task. In order to properly analyze the topologies, both knowledge in the field of finite element computations as well as computer-aided engineering and design are necessary. This multi-disciplinary engineering expertise can be expensive and not feasible for small and medium-sized businesses. By automating this vital step in a product development process, the utilization of topology optimizations in all product development processes can be greatly promoted. We propose a two-fold process for automatically processing density-based topology optimization results for future CAD design proposals: extracting a wireframe and deriving cross sections. The wireframe extraction supports mixed-element models featuring two-dimensional and three-dimensional finite elements and optional mirror symmetry consideration. The cross section extraction is currently available for three-dimensional finite elements. The wireframe extraction is fundamentally based on voxelization and skeletonization of a finite element- and density-based topology optimization. The cross section extraction makes use of the element density as well as the stress distributions from the topology optimization result. At first, load conditions are identified for each beam of the previously extracted wireframe and an appropriate beam profile is chosen from a set of profiles (currently circle and rectangle, both filled or hollow, and I-beams). Then, using a least square loss optimization and image processing-based shape averaging, the geometric dimensions of each selected beam profile are determined. In the end, a model is available which can be converted into a parametric CAD model for further design work.