Robust controller design for discrete uncertain multiple time-delay systems

We derive a variety of succinct criteria of robust stability for discrete uncertain systems which contain multiple delays and a class of series nonlinearities. Each result is expressed by a brief inequality and corresponds to compromise between simplicity and sharpness. The properties of norm are employed to investigate robustness conditions that guarantee asymptotic stability rather than ultimate boundedness of trajectories. It is shown that the uncertainties, nonlinearities, and delays are the factors of instability of the overall system, between which some compromise is necessary.