Research on the influence mechanism of assembly stress on reliability of space deployable mechanism

Abstract

The on-orbit performance of spaceborne SAR satellite mainly depends on the unwrapping precision of antenna panel, which is determined by its supporting pole system. The assembly stress of the pole system affects the antenna deployable precision in the assembly process of SAR antenna deployable mechanism. Aiming at this problem, this work presents a efficient method that the three-dimensional model of the deployment mechanism of SAR antenna is established, and the method of finite element simulation analysis is adopted. Prestress is applied to the pole system to simulate its assembly stress, and then we study the deformation law of the antenna panel under different assembly stress combinations of the mast system, and the mapping relationship is determined between the mast system and the flatness of the antenna panel. The most sensitive pole affected by the antenna panel deformation is obtained. The results show that the flatness of the antenna panel is related to the dimensional tolerance and position of the pole system, especially Large dimensional tolerance results in large deformation of antenna panel. In addition, the deformation area of antenna panel is determined by the assembly stress of different pole combinations. According to this research, it is concluded that the poles which should be controlled are obtained in the assembly process of the antenna deployable mechanism, which lays a theoretical foundation for the high precision assembly of the truss space deployable mechanism.