Abstract
The stabilization problem of linear uncertain delay systems by means of linear constant memoryless state feedback control is investigated here. The uncertain parameters and the time delays under consideration may take arbitrarily large values. In this case, the locations of uncertain elements in the system matrices play an important role. It has been shown that it is a necessary and sufficient condition for the stabilization of time-varying or timeinvariant uncertain systems without delays to have a particular geometric configuration called ASC or GASC, respectively. For 3 dimensional systems, it is shown here that if time-varying uncertain delay systems have an ASC, then the systems are stabilizable with regardless to the upper bounds of delays and uncertain parameters. Moreover, it is shown that the time-invariant uncertain delay system having a GASC can be stabilized on the same argument. The results obtained here imply that the stabilizability conditions are not deteriorated by the existence of time delays.
