Dynamic characteristics of launch vehicle and spacecraft connected by clamp band

Spacecraft is usually fastened to the launch vehicle by clamp band in the aerospace industry. The application of clamp band joint brings local stiffness variation to the launch vehicle and spacecraft (LV/SC) system and affects the dynamic characteristics of the system. In this paper, the dynamic responses of the LV/SC system to the vibration and impact excitations were studied, where the effect of the clamp band joint was taken into account. Firstly, the mathematical model of the axial stiffness of the clamp band joint was derived. In the model, contact and slippage between the components were accommodated. Then the stiffness model was employed to construct the coupling dynamic model for the LV/SC system using the finite element software ANSYS. Finally, modal analysis and response analysis were carried out on the coupling dynamic model to investigate the dynamic characteristics of the LV/SC system; the simulation results were compared with those based on the dynamic model where the launch vehicle and the spacecraft were considered to be fixed together to explore the effect of the clamp band joint on the LV/SC system.