Abstract: In the process of truss deployment of space diffraction telescope, the moment of unfolding and locking of each truss element will cause the elastic vibration of the member and have a great impact on the star and the main mirror. On the basis of considering the elastic deformation of the truss components, a flexible multibody system dynamics model with variable topology was established for the truss expansion and locking process according to the changes of the system topology and constraints, and the dynamic numerical analysis was carried out. When the truss element was locked, the action of the locking mechanism was simulated by applying strengthening torque and damping at the joint. The numerical simulation results show that at the moment of locking, the truss vibrates greatly in the longitudinal direction, and the impact force on the star and the main mirror shows a peak value, and each peak value is different and changes periodically. This phenomenon is caused by the elastic deformation of the flexible parts of the truss. The research results provide a technical reference for the structural design and dynamic control of the space diffraction telescope.

Key words:  , truss, deploy, variable topology, flexible, multibody system dynamics