Robust Shape Adjustment with Finite Element Model Updating for Mesh Reflectors

Mesh reflectors are widely employed for large space antennas due to their lightweight, compact, and easy package. To guarantee the reflector shape precision with acceptable manufacturing and assembly tolerances, mesh reflectors are designed with special shape adjustment mechanisms, namely, the length of some cables can be carefully adjusted when the reflectors are assembled. Shape adjustment plays a major role in achieving perfect reflector shape precision. In this paper, a robust method is proposed for shape adjustment of mesh reflectors with the consideration of the discrepancy between the mechanical behaviors of numerical models and actual reflectors. In this method, the measured nodal position in each shape adjustment iteration is also employed to update the numerical model so that this discrepancy is gradually decreased. A robust approach is used to determine the cable length change for the model updating and shape adjustment where the adverse effects of the discrepancy can be reduced. Numerical examples and experiments validate the proposed method.