Dynamic analysis of spatial trussed lunar lander

A spatial trussed lunar lander with four collapsible landing gears is used as a model. MSC Patran/Nastran software is adopted to analyze the mechanical characteristic of the lunar lander body, thus the affecting factors of the structure modes are got, and the first ten constrained modes of the prototype structure are put forward. At last, the re- sporlse curves of the lunar lander body with different critical damping ratio under the exciting load of low-frequency sine vibration and random vibration from the rocket are got, It is found that low-frequency sine vibration makes the lunar lander body resonate when its frequency is about 76.7 Hz, and random vibration whose frequency is about 200 Hz has more influence upon the lunar lander body. The critical damping ratio has remarkable influence on the peak value of the response curves of the lunar lander body with the two kinds of the excitation.