This paper describes the development of a ground test system for determining the thermal deformation of large antenna panels to be used in space. The system is designed to measure the deformation occurring as a result of temperature differences between the front and rear surfaces of the panel. In the experimental set-up, a symmetric honeycomb panel was used. The front surface of the panel was heated by infra-red radiation, and the deformation was determined using a fringe scanning moire system which measured the shape of the rear surface. It was found that the temperature differnce realeized by the system was of the same order as was estimated on the orbit. The variations in the temperature difference were less than 15% of the average value. The effects of temperature distribution on the deformation were evaluated to be negligible by a Finite Element Method (FEM) calculation.
