简介：Anoptimalactiveslidingmodecontrollerwithspecifieddecayratedesignisproposedtocontrolthewave-inducedoffshorejacket-typeplatformwithactivemassdamper(AMD).IrregularwaveloadingisapproximatedbyfinitesumsofFourierseries,anditsdynamiccharacteristicsaregovernedbyanexosystemderivedfromthelinearizedMorisonequation.Theoffshoreplatformsystemisfirstdecomposedintotwovirtualsubsystemsbasedonalineartransformation.ByconsideringthevelocityofAMDasavirtualcontrolforceforthefirstsubsystem,theoptimalvirtualcontrollerisderived.Furthermore,anoptimalslidingmodesurfacewithspecifieddecayrateisproposed.Then,theactiveslidingmodecontrollerisdesignedtoensurethatthestatetrajectoriesreachtheslidingsurfaceinfinitetimeandremainonitthereafter.Numericalsimulationisemployedtoverifytheeffectivenessoftheproposedapproach.