Structural Analysis And Optimization Of Cable Mesh Deployable Antenna

Deployable Astromesh antenna, which is one of the ideal structures of large deployable space antenna for satellites, has been obtained more and more attention in the field of aerospace because of the advantage of big diameter, light weight and low areal density and other characteristics. This dissertation mainly carries out the study of several key technological problems during the analysis and design of deployable Astromesh antenna, including proper design of the surface geometry of mesh reflectors, calculation of reflector surface error, multi-condition structural optimal design and software accomplishment.1. The core of cable-net structural design of deployable Astromesh antenna is mesh generation. On the basis of the definition of the reference sphere, numbers of mesh nodes and rules of units connection are given, followed by the coordinates of mesh nodes. Points on the sphere are also projected onto the reference ellipsoid to ensure that the shape of flat end plane of reflecting surface and working paraboloid will be consistent. Finally, the calculation of coordinates of mesh nodes on the working paraboloid are done by projecting the nodes on the reference ellipsoid onto paraboloid, durng which rules of units connection remain constant. In general, the shape of down-net is a paraboloid and the coordinates of down-net in horizontal projection plane agree with that of up-net.2. For deployable Astromesh antenna, the article proposes a new method to calculate the surface error based on best fitting by introducing area coordinates. Then we can establish a new form-finding model after applying the new surface error calculating methods to the form-finding model of deployable mesh antenna. Finally, simulation results demonstrates the efficiency and consistency of the proposed approach.3. This paper discusses the structural optimization problems of deployable mesh antenna considering multi-conditions. First, the article establishes the structural optimization model of composite cable-beam system,which takes the sizes of members and length of cable units as design variables, minimizing the weight of antenna as objectives, the surface error, material strength and cable tension in equilibrium state as constraints. Then author use sequential linear programming to solve the linear programming problem derived from the initial model. Finally, the examples show the optimization model is feasible.