The degree of material deformation under extreme conditions is related to the safety of automobile driving. In this paper, the four-node Hughes-Liu unit (H4 unit), a shell unit commonly used in high-speed collision simulation of automobiles, is constructed, and the stress coordinates of each node are transferred to the overall coordinate system, which facilitates the calculation of the force at each place. Combined with the dynamics of the spring, the Lagrange method nonlinear finite element solution equations are applied to calculate the plastic deformation of the material of the car in the process of high-speed collision. According to the simulation test and finite element solution results, the materials of the three key structural points, namely B-pillar, A-pillar, and front longitudinal beam, show more serious deformation when subjected to high-speed collision, which cannot guarantee the integrity of the door frame and the safety of the occupants, and need to be optimized.
