EFFECTS OF BOUNDARY PERTURBATIONS WITH DIFFERENT DISTRIBUTIONS ON SHAPE ACCURACY OF INFLATABLE ANTENNA REFLECTORS

The performance of inflatable antennas critically depended on the shape accuracy of the membrane reflectors. Based on the non-linear finite element method, this paper explores the effects of boundary perturbations on the shape and stress of inflatable antenna reflectors of different focal-length-to-diameter ratios and diameters, as well as the reasons for these effects. Three kinds of distributions of boundary are focused on, including uniform distribution, local distribution and waveform distribution. The sensitivity analyses are respectively conducted. The effects of three kinds of boundary perturbations are compared in effect region, effect extent, sensitivity value and wrinkling. The study shows that: the effects of uniform and waveform perturbations act on the whole reflector. In the edge effect regions, the translation and curvature change of surface coexist. In the central regions, only the translation occurs. The effect of local distribution is limited to a local area. Among three kinds of perturbations, the uniform perturbation imposes the largest effect on the shape accuracy. However, the local distribution and waveform distribution have higher sensitivity values. All kinds of distributions except outward uniform distribution lead to wrinkling in effect areas. In addition, the influences of focal-length-to- diameter ratios and diameters are discussed. Based on the work presented, suggestions are given on proper strategy in passive and active control of the shape accuracy of inflatable antenna reflectors.