Weight reduction and mechanical optimization through targeted insertion of hollow deformable inclusions
Lightweight construction offers enormous potential to save resources, for example, through reduced fuel consumption in the automotive and aircraft industry. In particular, the capacity of bearing mechanical load for light but softer materials such as rubber can be increased by integrating firm fibers. Here, we investigate the effect of mechanically stiff but hollow inclusions. In this way, weight can be reduced while simultaneously increasing mechanical stiffness and firmness. Nevertheless, such inclusions generally still deform to a certain degree under load. On the one hand, we work on corresponding tools of calculation and theoretical-analytical descriptions of resulting interactions between the inclusions and the surrounding soft material. On the other hand, we develop numerical simulation approaches to identify beneficial spatial arrangements of the inclusions that optimize the material behavior. In the long term, the idea behind this endeavor is to characterize ways of allowing for weight reduction while simultaneously maintaining mechanical stiffness and opening a possible later additional functionalization, without the need for large-scale redesign of corresponding components. 
