Output tracking for linear uncertain time-delay systems

The paper considers the problem of robust output tracking of an uncertain system with multiple delays in both the state and control vectors. The disturbances are assumed constant, unknown but bounded. A robust output tracking scheme is proposed. The scheme guarantees asymptotic tracking of the command reference output, when the mismatched portion of the uncertainties satisfies a certain bound condition. In addition, the paper presents robust output tracking schemes for a class of matched uncertain time-delay systems and matched and mismatched uncertain nondelay systems. A numerical example is given to illustrate the results