Experimental and numerical study of energy absorption in bio-inspired scutoid cellular structures

This study investigates the compressive behavior and energy absorption of bio-inspired scutoid cellular structures made from polylactic acid to enhance mechanical energy absorbers used in impact protection. Seven four-cell scutoid specimens with varied transition point positions and wall thicknesses were fabricated using additive manufacturing and tested under quasi-static compression. Numerical simulations were conducted using finite element analysis in Abaqus to complement the experiments. Results show that scutoid structures outperform equivalent honeycomb designs in energy absorption efficiency, with the highest performance achieved when the transition point is located near the mid-height of the cells. Increasing wall thickness improves all key energy absorption indicators. Design of experiments reveals inner wall thickness as the most significant factor affecting energy absorption. The findings demonstrate that optimizing transition point location and wall thickness significantly enhances the crashworthiness of scutoid structures, making them promising candidates for lightweight energy absorbers.