Energy Absorption Characteristics of a Bio-Inspired Multicell Thin-Walled Tube Based on a Locust’s Hind Leg

The increasing demand for impact resistance in landing gears of low-altitude aircraft necessitates the development of buffer structures that combine lightweight properties with high energy absorption efficiency. Inspired by the graded multicellular structure of a locust’s hind leg tibia, this paper proposes a bio-inspired multicellular thin-walled tube structure (circular bionic cell thin-walled tube structure, CTTs). The effects of cell number, wall thickness distribution, and curvature parameters on the crashworthiness of the structure are systematically investigated. The deformation modes, specific energy absorption (SEA), peak force, and crush force efficiency (CFE) are analyzed through finite-element simulations and axial impact tests. The results indicate that the structure achieves optimal energy absorption performance with a cell number of 8, an outer wall thickness of 0.5 mm, a cell wall thickness of 1.0 mm, and a curvature ratio R/r of 1.5, yielding a SEA of 34.25 J / g and a significantly improved CFE. The bio-inspired structure exhibits stable progressive folding deformation, offering a novel design strategy for high-performance unmanned aerial vehicle landing gears.