抄録
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. They selected the state feedback controller to realize the most robust one by minimizing a certain index with respect to the model uncertainties. It is, however, not sure to the system containing time-varying uncertainties.
In this paper, we extend 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 show the sufficient condition for exponential stability of the time-varying system.
It is also investigated that the minimum value of the index depends only on the assigned eigenvalues of the closed loop system. Moreover a new algorithm using penalty method, which restricts the domain for seeking the minimum value of the index, is presented. An example of designing lateral autopilot system of a missile is shown as application.
