High-precision modeling and collision simulation of small rotor UAV

The high-precision modeling and collision simulation of UAVs should be conducted to achieve the dynamic response of UAV and assess UAV safety. In this paper, a high-precision finite element model of small rotor logistics UAVs on the market was built in LS-DYNA. The process to model the connection structure between a range of parts of a UAV was elucidated in detail. The bolt, damping spring and rivet & thread were respectively simulated with “NRB + beam”, “NRB + discrete” and “spot weld”. By a series of static and dynamic material tests, the constitutive parameters of main materials of UAV structure were determined. Besides, a reasonable explicit time step was set by regulating the mass scaling of local elements. To verify whether the finite element model of UAV is accurate, UAV underwent a developed full-scale crash test. As revealed from the experimentally achieved results, the trend of impact load over time in collision simulation significantly complied with the experimentally achieved results, and the discrepancy between the maximum impact load peak and the experimentally achieved results only took up 6.54%. Moreover, the vital damaged parts, damaging process and failure mode of the UAV structure in the crash test were accurately characterized in the collision simulation. Thus, the UAV modeling and collision simulation was verified to exhibit feasibility. Lastly, with the verified UAV high-precision model, the impacting process, possible damaged parts and failure modes of UAV at the variety of angles and speeds were assessed. Accordingly, the proposed high-precision modeling and collision simulation of small rotor UAV is capable of saving the physical and time resources of UAV structural strength experiments, as well as effectively assessing the structural safety and improving the design of small rotor UAVs.