Abstract: The nonlinear dynamic responses with strong rigid-flexible coupling have horrible influence on structures and equipments. The rigid-flexible coupled nonlinear dynamic model of space membrane antenna was established, where the effect of second-order nonlinearity and rigid-flexible coupling on the stiffness, damping as well as loading was described. The influence of rigid body motion, such as initial velocity and acceleration, on elastic response was analyzed by numerical calculation. Besides, the natural frequency and damping were considered as well. It comes out that the frequency and the maximum deformation of the membrane response are both positively correlated with the rigid acceleration and velocity, but negatively correlated with damping; as natural frequency increases, the response frequency rises up while the deformation decreases. The rigid-flexible nonlinear model deduced in this paper will serve as the theoretical basis of dynamic analysis and surface control of flexible structures. In the meanwhile, the rigid-flexible coupling response characteristics can provide a significant reference for the maneuvering design and disturbance avoidance of membrane structure.

Key words: space membrane structure, nonlinear dynamics, rigid-flexible coupling, numerical calculation, frequency response analysis