Research On The Structure Of Space Deployable Antenna Based On Shape Memory Polymer Composites

This thesis discuss on the structure of the space deployable antenna, based on the shape memory polymer composites. In this thesis, a new type of epoxy shape memory polymer, which is proposed to be used for space structures, is discussed. The carbon-fiber-reinforced epoxy shape memory polymer composite (SMPC) was prepared. The author characterized its fundamental thermomechanical properties, and highlighted the performance in extreme space thermal environments. Furthermore, on this basis, using the SMPC, a space deployable antenna was designed, fabricated, a deployment process was demonstrated and its reflector precision was measured. Finally, to overcome the shortcoming of the structure, the author designed one kind of inflatable antenna structure, based on SMPC, and simulated its finite element.First of all, the author prepared a carbon fiber reinforced epoxy SMPC using an epoxy SMP synthesized in the author?s team. The SMPC showed excellent thermomechanical properties, large recoverable strain (50%) at glass transition temperature. The properties in extremely thermal environments in space (-100°C to +100°C temperature environment) was evaluated. For the shape-recovery performances, it showed good shape recovery ratio.Then, a deployable antenna fabricated by fiber reinforced SMPC was designed, fabricated, the deployment process was demonstrated and its reflector precision was measured. Optimization design of a SMPC antenna structure was conducted, including thickness curvature angle of SMPC thin shell and heating methods. Then a deployable antenna was fabricated, and electroactive actuation was realized (voltage 20V, power 54W, deployment duration 120s, and deployment angle 160°). The moment of each thin shell decreased linearly. The deploy velocity first rise and then decreased,and acceleration is nonlinearly. Under the indoor conditions, the SMPC antenna?s precision was measured as 6.796mm.Finally, through analysis of good and bad points of SMPC solid surface antenna and SMPC thin shell deployable antenna, the author propose a design of the SMPC inflatable antenna, which collection both merit in a body, and simulate its finite element.