Design and fabrication of foam-filled topology optimized composite structures using an improved non-monotonic interpolation function

Spatial topology and foam-filled structures are prominent macroscale characteristics observed in avian feathers and bones. However, the extraction of uniform thickness shell in a topology optimization process as well as fabricated by carbon fiber reinforced plastic is still challenge. This paper proposed a integration framework on the design and manufacturing of the topology optimized structure with rigid shell and foam filled. A modified non-monotonic function is carried out to interpolate the border coat and the infill foam, directly extract an unique coat from the single material topology optimization process. The sensitivities analyze the non-monotonic interpolation, objective and constraint considered in the optimization procedure. With this interpolation and control subsequent, we come up with a dual-molding method to fabricate the optimized structure with topology layout, rigid shell and foam infill. We compare the stiffness performance of the composite with the single material topology optimization result to discover the improvement of proposed method. The result apply to the laser altimeter sensor bracket of unmanned helicopter with high load bearing stiffness and limited design area. These bio-inspired composite with foam infill and rigid shell will improve synthetic layout that maximized the structural performance for potential use in the future transportation system.