Tie-System Calibration for the Experimental Setup of Large Deployable Reflectors

Abstract

The trade-off between the design phase and the experimental setup is crucial in satisfying the accuracy requirements of large deployable reflectors. Manufacturing errors and tolerances change the root mean square (RMS) of the reflecting surface and require careful calibration of the tie-rod system to be able to fit into the initial design specifications. To give a possible solution to this problem, two calibration methods—for rigid and flexible ring truss supports, respectively—are described in this study. Starting from the acquired experimental data on the net nodal co-ordinates, the initial problem of satisfying the static equilibrium with the measured configuration is described. Then, two constrained optimization problems (for rigid or flexible ring truss supports) are defined to meet the desired RMS accuracy of the reflecting surface by modifying the tie lengths. Finally, a case study to demonstrate the validity of the proposed methods is presented.