Fault-tolerant decentralized control for large space structures

This paper considers position and attitude control of large space structures composed of a number of subsystems which are interconnected by springs and dampers. A decentralized control law of dynamic displacement feedback compatible with subsystems is applied under the assumption that sensors and actuators are collocated. The overall closed-loop system is robustly stable against perturbations in mass, damping, and stiffness if rigid modes of each subsystem are controllable and observable. The objective of this paper is to derive conditions under which stability of the overall system is preserved even when some local controllers fail. The conditions are expressed in terms of the stiffness (or damping) matrices and interconnection location matrices of the subsystems whose local controllers fail.