Distributed Actuation Optimization of In-Orbit Membrane Structures Based on Clustering
Wenxiang Zhou, Kai Luo, Qiang Tian, Haiyan Hu
Abstract: With recent advances in the technology of deployable space structures, the membrane reflectors (with large size but light weight) for satellite antennas are highly demanded. To maintain high surface precision of a membrane reflector, it needs to be actively controlled in orbit via a distributed actuation system. This paper presents the group-control optimization of distributed actuation with a limited number of input channels based on the full-orbital-period thermal-analysis and clustering algorithm. The study begins with the analysis of the thermal radiations on an inflated membrane reflector in a geosynchronous orbit, and it gives the database of temperature distribution. Then, the mechanics model of the membrane reflector under thermal loads and distributed electric actuation is established based on the modal expansion of the Fourier–Bessel series to simulate its thermal deformations. Afterward, the group-control optimization based on the clustering algorithm and thermal-analysis data is performed to successively involve the various constraint conditions. With the proposed method, a unified control mode of the distributed actuation is derived to remove the necessity of online computation for almost all the extreme cases of thermal deformations of the reflector in orbit. Finally, the method is validated via the comparison of numerical and experimental results.
