On capability of sampled-data feedback for a class of semi-parametric uncertain systems

In this paper, we consider a class of first order semi-parametric sampled-data control systems where there is an unknown parameter in the input channel, in addition to the nonparametric uncertainties of the system, aiming at understanding the capability and limitations of the sampled-data feedback. We will demonstrate that the sufficient condition to globally stabilize the system by the sampled-data feedback is Lh <; log 4, where h is the sampling rate and L is the linear growth rate describing the size of the uncertainty of the nonparametric part. This value is the same as that first obtained in [8] for a class of purely nonpara-metric systems, and the result implies that the capability of sampled-data feedback may not be influenced by the parameterized uncertainty in the systems just as what has been shown in the recent result [11].