Analysis And Optimization Of The Feed Cable Supporting Structure And Active Cable-mesh Main Reflector For Super Antenna

With the development of super antenna and space antenna, cable structure attracts extensive interest and is widely employed, of which one representative example is the new design project of large radio telescope. The cable supporting system in which 6 cables move the cabin and the active cable-mesh reflector, a portion of which can be deformed to a dynamic paraboloid, are two highlights of the project. The mechanics problems of the two subsystems are investigated.As for the cable supporting system, static model of the cable supporting system is obtained based on the analytical catenary of a cable, on which the stiffness matrix and the torsion stiffness are deduced.The rigid-flexible coupled dynamic model of Stewart platform suspended by the cable supporting system is established to investigate the response of feed cabin to the disturbance of Stewart platform. The responses of feed cabin suspended by the 6-cable and 8-cable system are discussed.As far as the active cable-mesh reflector is concerned, the length of cable segment needs to be determined firstly, and then an equilibrium state locating on base spherical surface under certain condition will be specified as the initial reference configuration. Finally, the illuminated area by feed of the reflector can be deformed to a paraboloid in time.The precision of the surface-fitting cable-mesh reflector relates to the curve of cable segment, and the length of cable segment is first solved. An approach suitable to solve the initial equilibrium configuration of cable-mesh reflector is presented, in which a node position optimization or a cable segment length optimization can be employed to get an ideal drag force pattern.The bias distribution vector is introduced to describe the divergence of all nodes on the cable-mesh, which forms the displacement field in the adjustment. And two methods, namely normal displacement method and least square method are provided to determine the displacement field, on which the drag force increment in adjustment can be solve by a pseudo-inverse.Node position and the stress distribution of the surface-fitting cable-mesh reflector are strong coupled, both of which affect the surface precision. To achieve the given precision, node position and the stress distribution of cable-mesh are adjusted simultaneously in order that the node position can be changed, at the same time the...