Topology optimisation method for crashworthiness design using Hybrid Cellular Automata and thin-walled ground structures

Crashworthiness is one of the most demanding design cases for vehicle structures. Until a few years ago, it was mainly addressed using trial and error approaches; but recently, automated structural optimisation for crashworthiness design got more and more popular. So far, most relevant applications use size or shape optimisation. Nevertheless, the ultimate way to achieve significant mass reduction is to use topology optimisation. While topology optimisation for static mechanics is a well established field of research, applications to crashworthiness can be rarely found. Due to high non-linearity of crash simulation, classic topology optimisation methods cannot be applied directly to crashworthiness design. Therefore, alternative methods have been developed. This paper first presents the available methods for topology optimisation in crashworthiness design. A discussion of these methods highlights the opportunity to develop an alternative method which is detailed in the second section of this paper. Then two application examples are presented to showcase the interest and capabilities of this method.