Innovative Structure Design Of Large Space Deployable Membrane Antenna

Space-based warning radar is an important equipment to protect national security with the advantages of all-weather and high position.The radar is far away from the target,so it needs a huge aperture to play its performance of detection.The membrane structure has become the first choice for the space-based warning radar because of its light weight and small volume.The deployable membrane antenna has not been applied to engineering applications,and there are still many technical problems need to be solved.This paper will study the following aspects of the structure design of large space deployable membrane antenna:1.Put forward a innovative design scheme of the deployable mechanism.The simple model of basic unit was manufactured and the motion process of mechanism is verified by experiments.The deployable mechanism and its basic unit is analyzed in detail,and the packing efficiency,surface density and storage height of the deployable mechanism were compared to other similar structures,and the indicators are in the forefront of similar deployable mechanisms.2.The mechanical properties of the deployable mechanism was studied.The finite element model of folding state and unfolding state of deployable mechanism with 20 m aperture was established,and the modal analysis is carried out.The dynamic modeling of the mechanism with 20 m aperture was established by the multi-body dynamics analysis software——ADAMS.The kinematics and dynamics simulation of the mechanism were analyzed,and the mechanical properties of the mechanism in the process of deployment were studied.3.Based on the innovative deployable mechanism,the finite element model of membrane antenna with 20 m aperture was established,and a new method of the nonlinear modeling for the cable-membrane structure was put forward.This method considered the slipping between cables and membrane in the boundary of membrane antenna,and the spring element was used to replace the traditional shared node modeling method,and the slipping between cables and membrane was simulated by deformation of the spring element.In addition,a detailed analysis of the surface precision of the membrane antenna under the conditions such as microgravity of geosynchronous orbit,radiation in space and creases in the membrane surface and so on.4.The boundary shape of the membrane was optimized by minimizing the surface precision of membrane.The boundary of the membrane is regard as a spline curve,and the design variables are displacements of the control points of the curve for this optimization problem,and the boundary shape corresponding to the optimum surface precision of membrane is determined by optimization.