Numerical investigation on energy absorption characteristics of impact-resistant lightweight structure of bio-mimetic micro aerial vehicle

With the increasing development of micro aerial vehicle, the impact resistance of the structure has gradually become a research hotspot. The beetle's exoskeleton not only provides important protection for its body and flexible wings but also ensures its good flight performance. Therefore, the beetle's exoskeleton has become an important research content in the field of bio-mimetic micro aerial vehicles. In this study, taking the internal structure of the beetle's exoskeleton as the research object, a kind of bio-mimetic lightweight thin-walled impact-resistant structure that can be used in the micro aerial vehicle is proposed. The energy absorption characteristics of the bio-mimetic structure under axial impact loading are calculated and analyzed by the numerical simulation method, and the important parameters such as impact angle, protective layer thickness, and wall thickness are optimized and discussed. The main results include that the filling method of the hollow column has a certain correlation with the energy absorption characteristics of the structure under different impact angles, and among the different cross-sectional shapes, the hollow column with a circular cross-sectional configuration has the best energy absorption ability. In addition, as the internal space of the structure increase exponentially, the decrease of specific energy absorption value of the bio-mimetic structure is relatively small. Finally, the wall thickness with good energy absorption characteristics is about 1.5 mm, while the preferred span length of the structure is between 90 and 120 mm.