Shape and geometry design for self-locked energy absorption systems

The self-locked energy absorption system has been recently proposed to prevent the lateral splashing of thin-walled tubes under impact loadings without any constraints, which breaks through the limitation of round tube systems. To improve the energy absorption capacity and efficiency of the self-locked system, we explore eight new designs on the shape and geometry of the tubes, and investigate the deformed configurations and energy absorption performance of these models by compression experiments and FEM simulations. It is found that the ellipse- and pentagon- shaped enclosed self-lock models perform better if the tube is made of soft materials like resin, and the ellipse-shaped unenclosed self-lock model performs better if the tube is made of hard materials like steel. Furthermore, compared with the widely-used round tube system and the ordinary self-locked system, the system composed by the new-proposed self-lock tubes inherits the self-locking effect of ordinary self-lock tubes, and significantly improves the energy absorption properties. This work can provide guidelines for the design and application of the self-lock tube system in engineering applications.