Nonlinear finite element modeling and simulation for landing leg of lunar lander

In order to accurately predict the load attenuation and energy absorption capabilities of landing leg during the landing event for supporting the design and optimization of landing gear mechanism, a new approach of using nonlinear finite element method in landing impact dynamic analysis was proposed. A detailed finite element model of landing leg was constructed and ABAQUS/Explicit was selected as the solver. Mass scaling technique was used to increase computational efficiency. Landing dynamic simulation of two landing scenarios were carried out, and the validity of analysis results were verified by comparison with test data. Results indicate that nonlinear finite element model with varied nonlinear factors can predict the landing performance of landing leg precisely. The flexibility of landing leg has a great effect on the friction between the inner and outer cylinders of leg struts, and the friction force can be decreased by increasing the leg stiffness.