Structural design and self-locking performance verification of the snap-fit spatial self-locking energy absorption system under the impact loading

There are increasingly high performance requirements of energy-absorbing systems in aerospace, defense and military, transportation and other fields, especially in the field of emergency protection where the study of self-locking characteristics is of great significance. In this paper, an energy absorption system is designed by snap-fit thin-walled tubes, which can be edited, easy to assemble quickly and spatial omnidirectional self-locking, and the spatial self-locking characteristic of the system was verified by numerical simulation under the uniform/concentrated impact loadings. The results show that the energy-absorbing system can withstand the uniform/concentrated impact loadings in all directions in space. Furthermore, the good comprehensive performance of the loading condition in direction 3 (α = 90 deg, β = 0 deg) was verified by the quantitative analysis of the complex proportional assessment (COPRAS) method and the qualitative analysis of Radar Diagram method.