Observer-based robust stabilization for uncertain systems with unknown time-varying delay

Thispaperfocusesontheproblemofrobuststabiiizationforaclassoflinearsystemswithuncertainparametersandtimevaryingdelaysinstates.Theparameteruncertaintyiscontinuous,timevarying,andnorm-bounded.Thestatedelayisunknownandtimevarying.Thestatesofthesystemarenotallmeasurableandanobserverisconstructedtoestimatethestates.Ifalinearmatrixinequality(LMI)issolvable,thegainsofthecontrollerandobservercanbeobtainedfromthesolutionoftheLMI.Theobserverandcontrolleraredependentonthesizeoftimedelayandonthesizeofdelayderivative.Finally,anexampleisgiventoillustratetheeffectivenessoftheproposedcontrolmethod.