An optimization approach to control reconfiguration

An optimization algorithm for the problem of control reconfiguration in res ponse to operating condition changes or abrupt system component failures is presented here. The algorithm utilizes a version of the Broyden-Fletcher-G oldfarb-Shanno (BFGS) optimization method of conjugate directions. The algo rithm provides an output feedback controller that not only stabilizes the n ew /impaired system, when possible, but also preserves much of the dynamics of the original/unfailed system. The design is such that the closed-loop s ystem is robust with respect to inevitable uncertainties/modelling errors o n the state-space matrices of the impaired system. The algorithm is applied to an aircraft longitudinal control system, for which two severe cases of failure are considered, first the loss of an actuator and then the loss of a sensor in addition to the actuator loss.