Image: Structural optimization of an L-shaped beam subject to global stress constraints. Courtesy of Erik Holmberg (c).
Mechanical and structural engineers have always strived to make as efficient use of material as possible, e.g. by making structures as light as possible yet able to carry the loads subjected to them, saving materials is desirable from practical, economical and environmental perspectives.
In the past, the search for more efficient structures was a trial-and-error process. However, in the last decades computational tools based on optimization theory have been developed that make it possible to find optimal structures more or less automatically – a research area known as Structural Optimization.
Optimal use of materials
At the division of Solid Mechanics at Linköping University researchers develops Finite Element based Structural Optimization tools that find optimal structures based on geometrical and material modifications.
In particular, so called Topology Optimization is based on a very general geometrical representation, where a design space (Fig. 2, left) is discretized into finite elements and each element has the possibility to be part of the optimal structure or not (Fig. 2, mid). By using a fine discretization, it is possible to find load-carrying structures that are superior to those developed by traditional trial-and-error approaches.
A promising development is to combine structural optimization and additive manufacturing, also known as 3D-printing, which is one of our currently active research directions. We are also investigating the possibility to view biological growth, for instance the adaptation of the bone structure and bone density to loading, as optimization processes.