Measurement And Adjustment Of Large Mesh Deployable Antenna

This thesis conducts a study on cable-net deployable antenna model, on which reflector accuracy measurement is tested by digital photogrammetry. On the basis of antenna model measurement data, the antenna finite element model updating method has been made intensive research. The main content of this thesis is as follows:1.Introduce the digital photogrammetry system in the application of deployable antenna measurement and its working principle. Combine with the Tianyuan digital photogrammetric system, discuss the influence of angle measurement, distance and measurement point distribution on the measuring accuracy and determine the measurement accuracy of this photogrammetric system. Methods that can improve measuring accuracy of the system are analyzed systematically. A reflector precision experiment on the 2m diameter cable-net deployable antenna is made and details the measurement process. Fitting formulas for the best fitting parabolic are deduced by least square method. Calculate the reflector accuracy of this deployable antenna model.2.The problem of cable-net deployable antenna structure finite element model updating is discussed deeply. By analyzing antenna structure stiffness matrix, we know the cable net antenna FEM model needs to be modified in the reason that the initial setting out length of each cable unit assembly in cable net structure for manufacturing antenna generates errors lead to the design of finite element models can not reflect the true physical mechanical properties of antenna model. So the main essence of the model updating is solving initial length variable quantity of the cable element.3.The 2m diameter cable-net deployable antenna finite element model updating is competed by measuring part of the physical information and solving antenna cable element initial length. After summarizing the rules in the model updating process, the modified empirical formula is deduced between the cable element length variable quantity and antenna design parameters. This empirical formula could provide guidance for designing future lager diameter cable-net deployable antenna.