Analysis on soft-landing dynamics and influence factors of lunar lander

The soft landing impact performance of lunar lander has a bearing on the success of moon mission. In order to accurately predict the dynamics response of a lunar lander during the landing process, the flexible model of the lunar lander is built by using nonlinear finite element method. This method comprehensively considers various nonlinear factors. For the sake of improving computational efficiency and guaranteeing simulation accuracy, a simplified model for cushion legs is presented, and an implicit algorithm is adopted to solve system kinematics equations. The effectiveness of the proposed simplified model and the simulation method are validated by comparison with test data. On this basis, the influence of center bodies with different damping and stiffness on the impact response of a payload is investigated, and then the theoretical explanation for the influence caused by stiffness is given. Results indicate that the acceleration response of the payload can be easily reduced by damping, and there is a negative correlation between the stiffness of the center body and the acceleration response peak value of the payload. This research provides theory basis and technical support for dynamics analysis and design of lunar lander.