MATLAB code Research Papers - Academia.edu (original) (raw)

Thetopicsofcontrolengineeringandsignalprocessingcontinuetoflourisanddevelop.Incommonwithgeneralscientifiinvestigation,newideas,concepts,andinterpretationsemergequitespontaneouslyandthesearethendiscussed,used,dis-cardedorsubsumedintotheprevailingsubjectparadigm.Sometimestheseinnova-tiveconceptscoalesceintoanewsub-disciplinewithinthebroadsubjecttapestryofcontrolandsignalprocessing.Thispreliminarybattlebetweenoldandnewusuallytakesplaceatconferences,throughtheInternetandinthejournalsofthediscipline.Afteralittlemorematurityhasbeenacquiredbythenewconceptsthenarchivalpublicationasascientifiorengineeringmonographmayoccur.Anewconceptincontrolandsignalprocessingisknowntohavearrivedwhensufficienmaterialhasevolvedforthetopictobetaughtasaspecializedtutorialworkshoporasacoursetoundergraduate,graduateorindustrialengineers.Ad-vancedTextbooksinControlandSignalProcessingaredesignedasavehicleforthesystematicpresentationofcoursematerialforbothpopularandinnovativetopicsinthediscipline.Itishopedthatprospectiveauthorswillwelcometheopportunitytopublishastructuredandsystematicpresentationofsomeoftheneweremergingcontrolandsignalprocessingtechnologiesinthetextbookseries.Itisalwaysinterestingtolookbackandreviewhowaparticularcontrolsys-temstheorydeveloped.Intimationsofparadigmchangeoftenseemtobeassociatedwithshortsharppapersthatmaketheacademiccommunitythinkagainabouttheprevailingtheoreticalorthodoxy;soitwaswithrobustcontroltheoryinwhichtheconferencepapersofGeorgeZamesandcolleagues(circa1980)andtheshortpaperofDoyleontherobustnessofcontrolsystemsusingtheverypopularlinearquadraticGaussiandesignmethodnowstandaslandmarkcontributionsthatinitiatedanewcontroldesignparadigm.Allthroughthe1980scameasteadystreamofpapersthatbegantochangetheverylanguageofcontrolitselfwithtermslikerobustness,sys-temuncertainty,H∞controldesignandμsynthesisenteringthecontrollexicon.ThisevolutionarydevelopmentwasvividlycapturedbyProfessorChristosG.Cas-sandraswritingintheIEEEControlSystemsMagazine(Vol.32,No.3,pp.10–13,2012)inashortinformalstudyarticleonpaperssubmittedtothepremiercontroltheoryconference,theCDC;hewrote“Theterm“robust”appearsinzerotitlesor abstractsin1971beforeshowingupin13–14%ofpapersin1991and2001”.Infactin1981,theproportionwasjust3.4%,andthiswasaroundthetimethattheacademiccommunitywasbeginningtotakenotethatchangewasathand.Throughoutthe1960sand1970stheformalismofstatespaceandthemethodsofoptimalcontrolwereintheascendantforsystemmodelingandacademiccontrolsystemdesign.Onefeatureofthisframeworkisthatitisabletoprovidesolutionsformultivariablesystemproblems.However,itwasfoundthatdespitecleveruseofadvancedmatrixanalysisandcomputer-aideddesignpackages,classicalcontrolfrequencydomaintechniquesdidnoteasilygeneralizetomultivariablesystems;amissingpartofthecontrolsystemstoolboxwasreallysuccessfulfrequencydo-maindesignmethodsformultivariablesystems.Thus,fromthe1980sonwardthetoolsofrobustcontrolformultivariablesystemsweredevelopedandrefinedandMATLAB®routinesweredevelopedtofacilitatetheimplementationofthenewde-signmethods.Asbefita“unifiedtheory,onenicefeatureofthenewrobustcon-trolmethodsisthatitsubsumestheterminologyofclassicalcontrolintothegeneralframework.Withthisdevelopmentoftherobustcontrolparadigm,thepublicationofthebookRobustControlDesignwithMATLAB®byDa-WeiGu,PetkoH.Petkov,andMihailKonstantinovintheAdvancedTextbooksinControlandSignalProcess-ingseriesin2005wasverytimelyandthebookwasconsideredtobeanexcellentadditiontothisseriesofadvancedcontroltextbooks.Withthebenefiofhindsight,withtheperspectiveofsevenmoreyearsofcon-solidationinrobustcontroltheoryandpractice,andwithanewMATLABRobustControlToolbox3available,Da-WeiGu,PetkoH.Petkov,andMihailKonstantinovhavenowproducedthissecondeditionoftheirbook.Therevisedtexthasgrownfrom13chaptersand389pagesto19chaptersandjustover460pages.ButmostsignificantlthetextbookhasaslightlydifferentandimprovedstructurethatmakestheMATLABmaterialmoreaccessibleandfocused.PartIstilllooksatthedif-ferentandbasicelementsofrobustcontroldesignprocedures.However,thereisausefulnewchapterongeneralresultsthatuseLinearMatrixInequalities(LMIs).ThenewlyintroducedPartIIpresentschaptersfocusingontheuseoftoolsandroutinesfromtheRobustControlToolboxVersion3.Thus,whereasinPartIthetheoryoftherobustcontrolproceduresisoutlined,inthisnewpart,theMATLABimplementationsarepresentedanddemonstrated.Finally,inPartIIIwefinsixin-depthdesignstudies,twoofwhichareentirelynew.Thecasestudiescarriedoverfromthefirseditionofthetextbookarethebenchmarksystemexamples,namely,hard-disc-drivecontrol,thetripleinvertedpendulumsystem,ahigh-puritydistil-lationsystem,andaflxiblemanipulatorsystem,whichisadistributed-parametersystem.Thetwonewcasestudiesareatwinrotoraerodynamicalsystemandaself-balancingtwo-wheeledrobot;bothsystemsthatareoftenfoundastestrigsinthecontrolengineeringteachinglaboratory;afeatureofthesetwonewdesignstudiesisthepresentationofexperimentalresultsfromlaboratorytest-rigstodemonstrateandassesstheperformanceoftherobustcontroldesigns.Wehavenowpassedthroughsome30yearsofconsolidationsincetheacademiccontrolcommunitybegantolookagainatthefoundationsofcontrolsystemde-signandformulatedanddevelopedtherobustcontrolparadigm.Thefactthatthe MATLABRobustControlToolboxhasreached“Version3”demonstrateshowro-bustcontrolandMATLABremainpervasivetoolsfortheacademicandindustrialcontrolengineeringcommunity.ThustheEditorsareverypleasedtowelcomethissecondeditionofRobustControlDesignwithMATLAB®.Itisavaluablecontri-butiontothelistofpublicationsintheAdvancedTextbooksinControlandSignalProcessingseries;theauthors’newstructureandmaterialbringsadditionalpeda-gogicalvaluetotheneweditionasanadvancedtextbookforteachingoncoursesandforself-studybythecontrolengineer.