Sampled-Data Optimal Design and Robust Stabilization

This paper considers sampled-data control of time-delay systems. First we show that under a certain nonpathological sampling condition, a sampled-data system is internally stable in continuous time if and only if the corresponding discretized system is stable in discrete time. Based on this, we then study two sampled-data design problems for (unstable) time-delay systems: ℋ2-optimal disturbance attenuation and robust stabilization. In both cases, the sampled-data problem can be recast via operator methods as exactly a discrete-time problem and hence be solved using known techniques.