Abstract
A dynamic system model often contains some structured uncertainties which can be expressed by parameter perturbations. Keel et al. developed an algorithm for obtaining a robust state feedback controller, which is available to time-invariant system.
In previous paper, we extended this method to the system with time-varying uncertainties which are expressed by the linear combination of time-varing parameters and the time-invariant matrices characterizing the structures of uncertainties. As a result, we showed the sufficient condition for exponential stability of the time-varying system.
On designing a feedback controller, we can not always detect all of the state-variables in the system. Moreover, in order to attain a controller in low cost, the number of state-variables used in it is needed to be reduced.
This paper presents a new method which robustly stabilizes the system with time-varying uncertainties by use of a constrained state feedback matrix in which some elements are restricted to be zero, and provides the sufficient condition for the obtained feedback system to be exponentially stable.
