Form-Finding Method for Large Mesh Reflector Antennas with Flexible Trusses Based on Stiffness Analysis

Abstract

The cable-net structure is an important part of the mesh reflector antenna, and it determines the accuracy of the reflector. Traditional approaches for designing mesh reflector antennas usually treat the supporting truss as rigid. However, with an increase in the antenna aperture, the flexibility of the supporting truss becomes more obvious, and thus, its deformation is not negligible. Although many form-finding approaches that consider the elastic deformation of the supporting truss have been proposed to date, their purpose is to adapt to the deformation rather than to reduce the deformation from the perspective of the cable-net design. Therefore, by analyzing the stiffness characteristics of the supporting truss, this study first proposes a new cable-net form-finding method that ensures that the deformation of the supporting truss is uniform and minimal under the action forces of the cable-net structure. Then, by considering the incremental equilibrium equation of the cable-net structure, the stiffness equation of the mesh reflector antenna is established. Subsequently, a novel form-finding strategy is presented, which is embedded into an iterative approach for exactly designing the mesh reflector antenna that considers the flexibility of the supporting truss. Finally, by making a comparison with the existing approaches, it is shown that the method proposed in this study can find a set of relatively uniform tensions and high surface accuracy under the premise of having only a small deformation of the supporting truss.