New Results on H8 Control of Input Delay Systems

The problem of delay-dependent H_infin control for systems with state and input delays is considered in this paper. By using the idea of delay fractioning, an improved H_infin performance criterion is proposed. Moreover, based on this criterion, a new procedure for designing delay-dependent H_infin state feedback controllers is obtained, which ensures that the closed-loop system is asymptotically stable with an H_infin disturbance attenuation level gamma. These results are shown, via extensive numerical examples, to be much less conservative than most of the existing ones in the literature.