Decentralized robust control of large space structures by local proper controllers using displacement output feedback

This paper considers robust decentralized control of large space structures composed of interconnected subsystems(substructures) by flexible links. A local controller is applied to each subsystem with collocated displacement/angle sensors and force/torque actuators. An N-th order proper controller using only displacement/angle feedback, is introduced at each input channel to control position and attitude of the space structures. It is shown that both the closed-loop subsystems and the overall closed-loop system become robustly stable under the condition in which the controller parameters are chosen to lead phase at appropriate frequencies in each subsystem.