Centralized/decentralized control for spacecraft formation flying near Sun-Earth L2 point

A new centralized and decentralized mixture control via virtual structure (VS) approach for the large number of spacecrafts formation flying is presented in this paper. To describe the formation clearly, the entire formation is considered as a main VS including several sub-VSs and every sub-VS includes several single spacecrafts. In this mixture control architecture, the decentralized architecture is utilized among sub-vss, while the centralized architecture is used among spacecrafts in every sub-VS, which is able to compromise the shortages of both major architectures to improve the system performance. After finishing the description of the formation, the control strategy is realized by designing the local control for single spacecraft and formation control for every sub-VS respectively. In the control designing, LQR control and near eigenaxis maneuver are presented to achieve the fuel-cost optimal. Also the formation feedback is imported into the controller to preserve the formation shape during the maneuver. Finally, the simulation is carried out and the results show that the new mixture control has the ability to ensure the stability and robustness for the large number of spacecraft formation flying.