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15MobileRobotsatWork15.1IntroductionRobotsofalltypesconstituteoneofthekeystohumansocialandeconomicdevelopment.Thefirstrobotsweredeviceswithoneormorearmsmakinghuman-likemotions.Inourdays,theshapeofrobotscoversaverylargerepertoryofformsincludingwheeledplatforms,mobilemanipulators,leggedbodies,animal-likerobots,andsoon.Alltheserobotscontributeinoneortheotherwaytohuman,industrial,agricultural,technical,andsociallifeimprovements.Thebenefitsofusingautonomousandintelligentmobilerobots(wheeledorlegged)inmedical,assistive,andserviceapplicationsarenumerous,andtheirpositiveimpactinmodernsocietyiscontinuouslyincreasing.Thepurposeofthepresentchapterispurelyencyclopedicandaimstoprovidethereaderasmallsetofmobilerobotsofvarioustypesthatareactuallyusedinmodernindustryandsociety[125].Specifically,thefollowingrobotcategoriesarediscussedwithrelevantphotosincluded:●mobilerobotsandmanipulatorsinthefactoryandindustry,●mobilerobotsinthesociety(rescue,guidance,hospital),●mobilerobotsforhomeservices(cleaning,otherservices),●assistivemobilerobots(autonomouswheelchairs,servicemobilemanipulatorsfortheimpaired),●mobiletelerobotsandwebrobots,●othermobilerobotapplications.Theaboveapplicationsillustratetheimportanceandvalueofmobilerobotsforachievingabetterqualityofhumanlifeinawidevarietyofdirections.15.2MobileRobotsintheFactoryandIndustryMobilerobotsusedonthefactoryshopflooraretypicallycalledautomatedorautonomousguidedvehicles(AGVs)andmovefollowingmarkersorwiresonthefloororemploysensorysystems(lasers,vision).AGVsareusedinfactoryformaterialhandling,producttransferfromoneplacetoanother,forinspectionandqualitycontrol,etc.TheyworkaroundtheclockcontributingtobettercontinuousIntroductiontoMobileRobotControl.DOI:(Northbrook,IL),actuallybeingatowtruckfollowingawireinthefloorinsteadofarail.Today,AGVsareprimarilylasernavigated,andcanbeprogrammedtocommunicatewithotherrobotstoassuresmoothproductmovementandstorageintheindustrialpremises.AllmodernflexiblemanufacturingsystemsuseAGVsforachievingtheirgoalsandassurefastandhigh-qualityproduction24haday.ThenavigationofAGVscanbeperformedinthefollowingways(Wikipediaarticle:Automated-Guided-Vehicles#Wired).●Wirednavigation—Awiredsensorplacedonthebottomoftheplatform(facingtheground)detectstheradiofrequencywhichistransmittedfromawireplacedinaslotabout1in.belowtheground.TheAGVisthenmovedfollowingthewire.●Guidetape-basednavigation—Thisnavigationtypeissuitableforautomatedguidedcarts(i.e.,light-dutyAGVs).Atapeisusedtoguidethevehicle,whichisequippedwithasuitableguidesensorenablingittofollowthepathofthetape.●Laser-basednavigation—Thisisawirelessnavigationprocesswhichisperformedbymountingretroreflectivetapeonwalls,poles,andmachines.TheAGVhasarotatingturretcarryingalasertransmitterandreceiver.Thelaserissentoffandthenreceivedagainallowingthecomputationofthevehicle’sorientation(andinsomecasesthedistance)automatically.TheAGVisequippedwithareflectormapstoredinmemory,andcancorrectitspositionbyafeedbackcontroltechnique(usingtheerrorbetweenthedesiredandreceivedmeasurement).●Gyroscope-basednavigation—Thisisaninertialguidancesystem.Transportersareembeddedintheflooroftheworkenvironment.TheAGVemploysthesetransporterstodetectthecorrectnessofitsroute,andagyroscopemeasuresthechangeinthedirectionofthevehicle.Thischange(error)isusedtocorrectthevehicle’smotionandreturnitonthepath.●Naturalfeatures-basednavigation—ThisallowstheAGVnavigationwithnoworkspaceretrofitting.Typically,oneormorerangefindersensors(laser,gyroscope,etc)areused,andtheextendedKalmanfilterorparticle/MonteCarlofiltersareusedforlocalizationandmapping.ThemostcommonsteeringtypeinfactoryAGVsisthedifferentialdrive.WhenthereareseveralAGVsworkingontheshopfloor,somekindoftrafficcontrolisrequired(forwardsensingcontrol,zonecontrol,etc.).TheapplicationsoffactoryandindustrialAGVsincludethefollowing:●Trailerloading—Pickupofpalletsfromconveyors,orstaginglanesanddeliverintoatraileraccordingtoaloadingpattern.●Rawmaterialhandling—Transportationofrawmaterials(metal,plastic,rubber,paper,etc.)receivedinthewarehouse,anddeliverytotheproperproductionline.●Finishedproducthandling—Transportationoffinishedgoodsfromtheproductionlinetostorageorshippingtocustomers.TheaboveapplicationsofAGVsareneededinmostmodernindustries—automotiveindustry,foodandbeverageindustry,paper-and-printindustry,chemical/pharmaceuticalindustry,manufacturingindustry,etc.Figures15.115.5showsomeAGVsusedinfactoriesandindustries,includingautonomousmobilemanipulators.636IntroductiontoMobileRobotControlFigure15.1TwoHitachiautonomouslyguidedvehiclesforthefactory.Source::TwomoreindustrialAGVs.(A)AdepthandlingAGV,(B)DTAVehiclesAGVpallettruck.Source: