Top 10 Tech Cars 2007

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34 IEEESpectrum|April2007|NA www.spectrum.ieee.orgElectric cars are backAboutAyEArAgo,theunitedStateswascomingoffagaso-linepriceshock,hybridelectricvehicleswerethestateoftheartinproduction-cartechnology,andso-calledplug-inhybridsweresomethingonlyafewgaragehackersandgreenextremistsdidforfun.theworldslargestcarcompany,generalMotorsCorp.,waslockedinaboardroomfightwhileitsNorthAmericanproductswith-eredonthevine.Ah,whatadifferenceayearmakes.today,thestateofthearthaspassedbeyondhybridstotechnolo-giesthatseemeddeadorridiculouslyexoticevenayearago:pureelectric-drivecars,includingfuel-cellvehicles;andplug-inhybrids,whichgivetheoptionofchargingthehybridsbatteriesdirectlyfromawallsocket.Dontlookforsuchcarsinshowroomsanytimesoon,butnoticethatsomeprettyspecificideasabouthowtheywillenterthemarketarestartingtoemerge.Andsomeofthoseideascomefromanunlikelysource:gMitself.butfirst,arealitycheck.Nearly50millioncarsandlighttrucksweresoldbymajormanufacturersworldwidelastyear.Noneofthosevehicleswerepureelectrics,andonly350000lessthan1percentwerehybridsofonesortoranother.by2025,saysPhilipgott,amarketforecasteratindustryanalystglobalInsight,12percentoflightvehiclessoldgloballywillbehybrids.Another12percent,hesays,willbediesels.Fewanalystswillevenhazardaguessaboutwhenthefirstpureelectricswillshowupintheshowroomsofmajormanufacturers.butgMisclearlystrivingtobethecompanythatputsthemthere.theautogiantannouncedseveralconceptsandtestfleetslastyear,allbasedonacommonsetofcomponentsusingelectricmotorstopowerthewheels.EvenasgMstruggledtoregainthehighgroundintech,ittookmorethanitsshareofpublicrelationshits.therewasthenewsthatitwillalmostcertainlyhavetocedetotoyotaitscrownastheworldslargestautomaker,eitherthisyearornext.ItsatitlegMhasheldfor70years.thecompanyshedmorethan30000employeesinNorthAmericalastyear(itpledgedtoreinvestsomeofthesavedcashintechnology).ManyobserversremainskepticalofgMsgoals,pointingtothethreedecadesthecompanyspentaggressivelybattlinganyandallregulationinthefieldsofsafety,emissions,andenergyusage,whilealitanyofgMinnovationslanguishedinlaboratories.therewasthecompanysromancewithhydrogen,forexample,exemplifiedbyHy-wire,gMs2002fuel-cellcar.CarspoweredbyhydrogenfuelcellsremainingMsvision,buttheyvebeenrecastasapieceofalargerstrategyinvolvingelectric-drivevehicles.Severalothermanufacturershaveunveiledfuel-cellconceptcars,includingHondawithitslatestFCX,whichmadeourlistthisyear.Andtheresmorethanonewaytospinwheelswithhydrogen:bMWandMazdaeachreleasedroughly100produc-tionvehicleswiththeabilitytoburnhydrogenintheirinternal-combustionengines.oneofthebiggestobstaclestohydrogen-poweredcarsisthelackofglobalhydrogenproductionanddistributioninfrastructure.buttheautoindustrywasjoltedbyincreasingspeculationlastyearthatasChinabuildsanetworkoffillingstations,itmightpossiblyusethemtodistributehydrogenaswellasgasolinejump-startingtheglobalfuel-cellvehicleindustryinawayimpossibleinmoredevel-opedmarkets.Suchastrategywouldassuagefears,asChinagoesmobile,ofavastgreenhousegasupsurge.theChinesemiddleclassisfindingoutwhatotherslearneddecadesago:carsarebulwarksofpersonalfreedomand,inthelargerpicture,ofeconomicgrowth.Fortunately,carstodayarecleaner,safer,morecapable,andmorereliablethanever.thattrendwillgoon,probablyforever.Meanwhile,ourcollectivevisionofwhatconstitutesacarisevolvingwiththetechnologythatmakesitgoandfeedsourfantasies. nIthaslithium-ionbatteriesandcomeswithachargingcable,justlikeyourcellphone.unlikeyourphone,however,itcangofromzeroto100kilometersperhourinlessthan4seconds,pinningyouagainstthebackofyourseatlikeafighterpilot.AnditlldoitwithalotlessnoiseandforuS$70000lessthanaFerrariF430.CreatedbyteslaMotors,aSiliconValleystart-upinSanCarlos,theteslaroadsterispoweredby6831mass-marketlithium-ionbatteriesandcostsabout$100000.Wantone?Fine,justputdown$75000nowandwaituntilsummer2008totakedelivery.theteslawasengineeredbyEnglandsLotus,renownedforitssmall,lightsportscars.thecarweighsjust1100kilograms(2425pounds),nearlyathirdofthatbatteryweight.Withits185-kilowattmotor,ithasatopspeedof210km/h(130mph).Aswithanypureelectriccar,thekeyparametersarethebatteriesrechargetime,energydensity,andusefullife.thepointofreference 2007 RoadsterA new kind of car from a Silicon Valley start-upPOWER PLANT n185-kWelectricmotorTRANSMISSION n2-speedelectricallyactuatedmanualnrear-wheeldriveCLAIMED RANGEn400kmMOREAmongthecarsbuyersaretheusualeco-celebs.ActorsgeorgeClooneyandDennisHaysberthaveplunkeddowndeposits.By John VoElckERwww.spectrum.ieee.org April2007|IEEESpectrum|NA35A new kind of car from a Silicon Valley start-upistheonlyrecentelectricvehiclefromamajormanufacturer,thelate,lamentedgeneralMotorsEV1.WhentheEV1wasintroducedin1996,itranonlead-acidbatteries,hadamaximumrangeof95km(60miles),andtookupto12hourstorecharge.theteslausesthesamelithium-ionbatteriesfoundinlaptopsanddigitalcameras.theirenergydensitycanbeashighas160watt-hoursperkilogramoratleastfourtimesthatoftypicallead-acidcells.Sotheteslahasa400-kmrangeand,bestofall,itcanrechargeinaslittleas3.5hours.unresolvedatthemomentistheissueofbattery life.Laptopbatteriesusuallydontlast the 10 years required of major auto-motivecomponents.Andteslahasindicateditexpectsitsbatterypackspowertodegradeupto30percent inasfewasfiveyearsor200000km.Morethanadozencompaniesaretryingtodeveloplithium-ionbatteriesinsizesandpackagessuitableforautomotiveuse.Whenoneofthemsucceeds,thetacticoflashingtogethermanysmallcellsbolsteredbyinstrumentationtomonitorandaccommodatethepowerorthermalvariancesamongthemprobablywillend.teslaMotors ishardly theonlynewEVmakerthesedays,thoughits$40millioninventurefundingputsitatthetopofthelist.globally,morethantwodozencompaniesareofferingelectriccarsofalldifferentsorts,fromdrabecono-boxestosupercarsliketheteslaroadster.Meanwhile,asofJanuary,teslahadsoldmorethan250carsatidysumat$100000each.thefirstcarsaresupposedtobedeliv-eredinSeptember,ifcrash-testanalysesandotheru.S.government-certificationrequire-mentsgosmoothly.teslaalsohasplans for a secondcar, asportyfour-seatsedancode-namedWhiteStar.thecompanyhopestolaunchthatcarby2010,atapriceof$50000.todoso,ithassetupanengineeringcenterinrochesterHills,Mich.,andplanstostaffitwithmorethan50engineers.nBy John VoElckERtESLAMotorS36 IEEESpectrum|April2007|NA www.spectrum.ieee.orgPOWER PLANTn100-kWhydrogenfuelcellCLAIMED FUEL EFFICIENCYn435kmfrom171litersofhydrogen,storedat350atmospheresMOREHondaletjournaliststakethecaroutonthebankedtesttrackatitsr&DcenterinJapan,atspeedsupto140km/h(87mph).top 10 tech carsPOWER PLANT nVortecV8(displacementnotreleasedatpresstime)TRANSMISSION ntwo-modehybridsystemntwo40-kWelectricmotorsnthreeplanetarygearsetsnAll-wheeldriveCLAIMED FUEL EFFICIENCYn10.5L/100km(estimated)MORE two-modehybridsystemisplannedforpickuptrucks,too.gMCsyukon is a strapping2500kilogramsunloaded.Inotherwords,itaintnoPrius.And yet, yukons f it ted with gMs newtwo-modehybrid systemuseessentially thesameprincipletoreduceenergyconsumptionastoyotascelebrity-friendlyit-car.Anelectricdrivecanpowerthevehicle,byitselfortogetherwiththecombustionengine.thebatterythatpowersthemotorischargedbytheengineandalsothroughregenerativebraking.beingasbigasitis,though,theyukonout-doesotherhybridsbyhavingtwoelectricdrivemotors,eachcapableof40kilowattssustained.Asinglemotorwithenoughtorquetomovesuchamasscouldntbeaccommodated insidethetruck.SogMsengineers,who ledadesigneffort that later included engineers fromDaimlerChryslerandbMWaswell,usedapairofelectricmotorsasystemgMhadpreviouslyputintoproductionforitshybridtransitbuses.AsinthePrius,theyukonsmotorsareactuallymotor/generatorsthatcanproducetorquewhenfedwithelectricityorviceversa.thesizeofthesystemwasconstrainedbytheneedtofititintothesamespaceasthecompanys6-speedautomatictransmission.Insideanalumi-numcasingarepackednotonlyfourfixedgearsbut(fromfronttorear)aplanetarygearsetandelectricmotor,aclutch,asecondplanetarygearsetandmotor,andthenafinalclutchandgearset.Ineachplanetarygearset,acentralgear(thesun)isspunbytheengineorelectricmotor.thesunissurroundedbyplanetgearsthatareinturnsurroundedbyaringgear,whichdrivesorisdrivenbyanothermotor.byvaryingthespeedatwhichtheplanetgearsspin,youalsochangethepowersplitbetweenthetorqueonthesunandthatontheringgear.beingabletosplitthepowerarbitrarilylikethatletsyouchanneljusttherightamountoftheenginespowertothewheels;therestisdevotedtochargingthebatteries.thetwomodesofgMssystemreferstothedifferentmixesofelectric-motorandcombustion-enginetorque.thefirst,orinput-split,modeisforlow-speedandlight-loadapplicationsfromlaunchthroughsecondgear.Asinexistingsingle-modehybridsystems,aplanetarygearsetsplitsenginepowerbetweenthewheelsandoneofthetwoelectricmotors.Actingasagenerator,thismotorchargesthebattery,whichpowerstheothermotor,whichdrivesthewheelsaswell.Inthismode,theengine-controlsystemalternatesamongelectric-only,engine/electric,andengine-onlydrive,choosingtheoptionthatprovidesthebestperformancewiththelowestfuelconsump-tion.Fromrest,energyfromthe300-voltnickel-metal-hydridebatteriespowersthedrivemotor,whichisquicklysupplementedbytorquefromtheengine.thesecond,orcompound-split,modeisforhighspeedsandheavyloads.Itprovideselectricassistinthethirdandfourthgears.Here,bothelectricmotorscanreceivetorquefromtheengine2008 yukonTwo-Mode hybridA hybrid heavy hauler FcX / conceptwww.spectrum.ieee.org April2007|IEEESpectrum|NA37Ifyouwantone,youllhavetowaituntil2018atleast,Hondasays.butstill,itslatestFCXconceptcartakeshydrogenfuel-cellpowertrains intoanew,sleeker realm. It saradical, stylishdeparture from thepreviousFCXsupright,slab-sidedhatchbackdesign.HondarevealeditsnewFCXthis past summer, around thesame time gM previewed itsChevroletSequelfuel-cellvehi-cle.but the twocarscouldntbemoredifferent.theSequelis a conventionally attractivesport-utilityvehicle,buttheFCXisalow,four-door,five-passengersedan.ItwouldlookrightathomeontheAutobahn,althoughitsmaxi-mumspeedof160kilometersperhour(100milesperhour)wouldntwinitmanyfriendsintheleftlane.Itispoweredbythecompanysthird-generation fuelcell,which is20percentsmallerand30percentlighter,andat100kilo-watts,14kilowattsmorepowerful.thenewV(forvertical)Flowstackstandsupright,andcanbepackagedinwhatusedtobecalledatransmissiontunnelbetweentheseats,low-eringthecenterofgravityanddoingawaywiththecharacteristictall,uprightdesignofmostpreviousfuel-cellvehicles.Moreimportant,thedesignhelpseliminateoneofthebiggestobstaclestomainstreamuseoffuel-cellcars:thecostandcomplexityofthesystemsneededtoletthecellswithstandsub-freezingtemperatureswhentheyrenotrunning.Waterisaby-productofthereactionthatliber-ateselectricalenergyinafuelcell.butanywaterremaininginthecellsstack,wherethereactionoccurs,wouldcausedamageifitfrozethere.InHondasvertical-flowdesign,gravityhelpsdrainthatwaterimprovingperformanceandreducingthepowerneededtopumpthestackdryeverytimethecaristurnedoff.AccordingtoHonda,thesystemworkssowellthatthecarcanstartattemperaturesaslowas20C.Witha smaller and lighter95-kWdrivemotor,thenewFCXscompletepowersystemis180kilogramslighterandalmost40percentsmaller than its predecessors. Hydrogenisstored ina 171-liter tankatapressureof350atmospheres,givingthecararangeof435km(270miles),Hondasays.HondaplanstoputthecarintoverylimitedproductioninJapannextyear.Still,itsastepforward:virtuallyallfuel-cellcarsbuiltsofarhavegoneintocarefullymaintainedandshel-teredfleetsatutilitycompanies,forexample.butHondasaysitisconsideringleasingthecarsforuS$600or$700amonthtointerestedpri-vatecitizens,togetreal-worldfeedbackonhowthenewFCXdrives,rides,andperforms. ncan a fuel-cell car be sexy?Standonastreetcornerinanymiddle-classsuburbinbrazilandwelloverhalfthecarswhizzingbywillbeflex-fuelvehiclescapa-bleofburningvariousmixturesofgasolineandethanol.Amongbrazilsmanyflex-fuelcars,aver-sionoftheFiatSienastandsoutbecauseitrunsonanyblendofethanolandgasoline,andalsoonpurenaturalgasaswell.Itburnsthenaturalgasfirstbecauseitsbrazilscheap-estcarfuel.theSiena stores the liquid fuel in a48-liter tankand thenaturalgas in two6.5-cubic-metercylindersinthetrunk.the1.4-Lenginehastwosetsofinjectors,oneforliquidfuelandasecondfornaturalgas.butthosearetheenginesonlymajorhardwaremodifications.theengine-controlunit(ECu)isthesameastheoneonordinarySienas.Itjustrunsmoresophisticatedsoftware.thecarsexistingsensorsmeasuretheairflow intocylinders, theengine speedandload,andthespecificfuelbeingsenttotheengine.thedataarefedtotheECu,whichusesthemtooptimizefuelinjectionandsparktiming.Mostimportant,theECuusesdata fromthesensor thatmonitorsoxygenintheexhausttovarytheair-fuelmixcontinuouslyuntilthatsensordetectsnooxygenremainingintheexhaust,indicat-ingcompletecombustion. n2007 Siena TetrafuelPOWER PLANT n1.4-L4-cylindern59kW(gasoline,ethanol)n50kW(naturalgas)TRANSMISSIONn5-speedmanualCLAIMED FUEL EFFICIENCY n5.6to7.7L/100km(gasoline)n8.3to11.5L/100km(ethanol)n15to20km/m3(naturalgas)MOREAt6270litersperhectare(670gallonsperacre),brazilsproductionofethanolfromsugarcaneisnearlytwiceasefficientasu.S.productionfromcorn,accordingtotheEarthPolicyInstitute.Research and translation for this segment was provided by Erico Guizzo.Auto omnivoreandpowerfromthebattery.thesecondandthirdplanetarygearsetsnotonlysplittheenginepoweramongthedrivewheelsandtheelectricmotors,theycanmultiplyalltorquetodelivermaximumpowertothewheels.Controllingitallaremicroprocessors.Infact,accordingtochiefengineertimCrewe,70percentof the total effort involved indesigningandtestingthesystemwenttowardcontrollogic.thatlogicanalyzeshundredsofinputsevery10milliseconds,includingvehicleload,engineoperations,batteryparameters,andthetemperaturesinthehigh-voltageelec-triccomponents.Dependingonvehiclespeedandpowerrequirements,onemotor-generatormayassisttheengine,orprovideregenerativebraking,withtheothershutdownforgreaterefficiency.orbothmotorscanprovideboostorbrakingsimultaneously.Andthecombina-tionofplanetarygearsetsandelectricmotorssmoothstheshiftingamongmodes,sothatenginespeedcanstayconstantevenasitvar-iestheelectricpowerdeliveredtothebatteryordrivewheels.Whencoupledwithcylinderdeactivation,thetwo-modehybridsystemisexpectedtoimproveoverallfueleconomyby25percent,to10or11 litersper100kilometers(about22milespergallon).Forcomparison, thestandardgMCyukongets15to16L/100km(roughly15mpg)inthecityand11to12L/100km(20mpg)onthehighway,accordingtotheu.S.EnvironmentalProtectionAgency. ntoP:AMErICANHoNDAMotorCo.;LEFt:gENErALMotorSCorP.;rIgHt:FIAt38 IEEESpectrum|April2007|NA www.spectrum.ieee.orgPOWER PLANT n120-kWelectricmotornturbocharged1-L3-cylinderenginen53-kWgenerator:recharges16-kWhbatterypackTRANSMISSION nNone;electricmotordrivesfrontwheelsMOREoneoftwocarsthisyearnamedforanelectricitypioneer,theotherbeingthetesla. Volt / conceptPOWER PLANT n125-kW1.4-Lturbochargedandsupercharged4-cylinderTRANSMISSIONn6-speedmanualnFront-wheeldriveCLAIMED FUEL EFFICIENCY n7.2L/100kmMOREAfterhistestrun,notoriouslyirritablereviewerJeremyClarksoncalleditoneofthef iveworstcarshehaseverdriven.Powerful small-displacementengineshavealwaysbeenaEuropeanspecialty.buteveninEurope,anenginethatputsoutmorethan75kilowatts(100horsepower)perliterofdis-placementisnotable.Soonethatgets125kW(168hp)and240newtonmetersoftorquefrom1.4litersisquiteanachievement.throwinfuelconsumptionof7.2litersper100kilometers(33milespergallon), andyouve reallygotsomethingtocheerabout.SoletshearitforVolkswagensgolfgtwith thetSItwincharger engine.VWsgoalwastoreducecarbondiox-ideemissionswhilemaintainingpower,torque,anddrivingcharacteristicsinanenginethatcouldbeproducedinhighvolumesforavarietyofvehicles.theresultingenginedeliversthehighestspecificpowerofanymass-produced4-cylinder,andthesametorqueasa2.3-Lenginewhileusing20percentlessfuel.VWsengineersoptedfortheconventionalapproachtomaximizingkilowattsperliter:startwithsmalldisplacement,andcoaxouteverypos-siblekilowatt.todothis,theirunusualtrickwastousebothasuperchargerandaturbocharger.Eachisessentiallyapumpthatpushesmoreairintothecylinder,allowingmorefueltobeused,therebyincreasinganenginespower.butasuperchargerisbasicallyanairpumpdrivenbygearsorabeltfromtheenginescrankshaft,whileaturbochargerisasmallturbinespunbytheforceofescapingexhaustgases.becauseitsdrivenoffthecrankshaft,asuperchargercansupplyadditionalairtothecombustionprocessevenatlowenginespeed.ontheotherhand,aturbohastospooluptoitsoperatingspeed,whichhappensonlywhentheengineisrunningfastenoughtogeneratesignificantexhaustpressuretospin it.thedelaybetweenadriveracceleratingandtheturboboostcomingon iscalledturbo lag.VWssuperchargercompensatesforthatlag.below2400revolutionsperminute, thesuperchargercanincreasethepressureoftheairprovidedtothecombustionprocessbyupto150kilopascals(about1.5atmospheres).underaccelerationfrom2400to3500rpm,thesuper-chargerstaysengagedwhiletheturbospoolsup.oncetheturbonearsitsmaximumboostof250kilopascals(2.5atmospheres),abypassflapswitchestheairsupplyfromthesuperchargertotheturbo.theintegrationofthetwoprovideshightorquefrom1750rpmto4500rpm. n2007 Golf GT TSIRecipe for fun: take a turbo and add a blowerLEFt:VoLkSWAgEN;bELoW:gENErALMotorSCorP.top 10 tech carswww.spectrum.ieee.org April2007|IEEESpectrum|NA39Hybrid-electricvehicleshavebeenavailableforadecadenow.Andwithina fewyears,so-calledplug-inhybridswillofferbeefierbatteriesthatcanberechargedfromawallsocket,aswellasbythevehiclesinternal-combustionengine.butbothvariantsarestilladaptedfromthesamedesignhandeddownduringacenturyofmechanicallydrivencars,inwhichtheenginestorqueistransferredmechanicallytothewheels.Amoreradicaldesignistheserieshybridelectriccardrivenbyoneormoreelectricmotorspoweredbybatteries that canberechargedbythecombustionengine.Intheseriesconfiguration,thecombustionenginecannotdrivethewheelsdirectly;itswitcheson,onlyasneeded,torunabackupgenera-torthatrechargesthebatteriesontripsthatexceedthecarsall-electricrange.theChevroletVolt,whichstoletheshowatDetroit sNorthAmerican InternationalAutoShowinJanuary,isthefirst-everserieshybridconcept vehicle shownbyamajorcarmaker.Its1-liter,3-cylinderturbochargedenginerunsanonboard53-kilowattgeneratorthatrechargesa16-kilowatt-hourlithium-ionbatterymadeupof804-voltcells.thatbatterypowersthecarthrougha120-kWelectricmotordelivering320newtonmetersofpeaktorque,givinganall-electricrange estimated at 65 kilometers (about40miles).theplug-inrechargetimelikelywillbe6.5hoursorless.Andthe45-Lgasolinetankgivesalmost1000kmbetweenrefuelings.onpaper,anyway.Wedonthaveabatterypackyetfortheconcept,acknowledgestonyPosawatz,thevehiclelinedirector,whocon-firmedthatthecarshowninDetroitdoesntyet runso its rangehasbeenestimatedfromlabtests.Amongotherqualificationsforautomotiveuse,lithium-ionbatterypacksmustlast10yearsorlongerthroughmorethan4000fullcharge-dischargecycles.theVoltisthefirstofseveralconceptsthatareexpectedtousewhatgMcallsitsE-flexplatformforelectricallydrivenvehi-cles.Startingaround2010,gMplanstobuildavarietyofsubcompactvehiclesthesizeofanopelAstraonabasicarchitecturethataccommodatesE-flexcomponents.Somewillhavecombustionengines,somearelikelytobeparallelhybridswithplug-incapability,andothersmaybeserialhybridsliketheVolt.gMsannouncementthatitwouldproducecarsusingE-flexchangedtheVoltfromjustanothershinyconcepttoapossibleprecur-sorofatrulyradicalshiftindrivetechnology.DuringtheVoltsunveiling,robertA.Lutz,gMsvicechairmanforproductdevelopment,wasclear:gMintendstosellcarspoweredbyelectricity.but,understandably,thecompanywontcommittoadatefordoingsountilitcangetsufficientlypowerfulanddurablelithium-ionbatteriesforautomotiveuse. nGMs vision of an electric-drive futurePOWER PLANTn2.5-L181-kWturbochargedflat-4(orhorizontallyopposed4-cylinder)TRANSMISSIONn5-speedautomaticnAll-wheeldriveCLAIMED FUEL EFFICIENCY n9to11.8L/100kmMOREtestingthethreedifferentmodesofSubarusSI-Drivemayposeachallengeforgovernmentagencies.SubaruhasalwaysbeenaJekyll-and-Hydecompany.Itssensibleall-wheel-drivestationwagonssit in thesameshowroomsas theirunrulyalter egos, suchas the fast, road-huggingImprezaWrXsedans,developedovermanyyearsofpunishingoff-roadrallies.NowSubaruhas introduced technologytoletdriverschoosesensibleorwicked?bytwistingadialontheconsole.theSubaruIntelligentDrive(SI-Drive)sys-temletsdriversselectoneofthreemodes:Intelligent,Sport,orSportSharp.Itcomesstandardonthree2007modelsoneofthemtheoutback2.5Xtwithautomatictransmissionandmoreareduenextyear.theturbocharged2.5-literdouble-overhead-camengineinthe2.5Xtinwhichthecylindersarehorizontallyopposed,likeaPorsches,tolowerthecenterofgravityproduces181kilowatts(243horsepower)andarousing327newtonmeters(241foot-pounds)oftorque.AsyouchangeSI-Drivemodes,thesystemscontrolsoftwarerevisessettingsfortheenginecontrol,automatic-transmissionshiftpoints,andthrottleresponse.InIntelligentmode,thesystemlimitsenginetorqueto309Nm,therebycuttingmaximumpowerbyroughly20percent.Italsomakesthrottleresponsesmootherandmoregradual,improvingthefuelmileagebyupto10percent,Subarusays.theSportmodesharpensthrottleresponsetofavoraccelerationandpoweroverfueleffi-ciency.thismodeisbestforfreewayandsubur-bandrivingandinhillyterrain,Subarusays.theSportSharpmodeemphasizesinstan-taneouspowerdelivery.Itsusefulforpassing.remappedshiftpointsholdthecarinitslowergearslonger,improvingaccelerationbymorethan50percent comparedwith Intelligentmode,Subarusays,andmimickingthewild-childbehavioroftheWrX.the ideaofasingleenginewithmultiplepersonalitieshadlongbeenthedreamoftoshioMasuda,SubarusprojectgeneralmanagerfortheLegacyoutbackline.Despiteskepticismthatsuchasystemwaspossible,oneofhisengineersbuiltaprototypeofwhatwouldbecometheSI-Driveandinstalleditinatestmule.thatcargraduallywonmanagementovertotheidea.theteamschallengelayinthefactthatofferingthreeperformanceprofilesrequiredthreetimesasmuchsoftwaredevelopmentandtesting. n2007 outback 2.5XTA sensible car acquires multiple personalitiesSubAruoFAMErICA40 IEEESpectrum|April2007|NA www.spectrum.ieee.orgPOWER PLANT n4.2-L309-kWV8TRANSMISSIONn6-speedmanualnAll-wheeldriveCLAIMED FUEL EFFICIENCY n12to17L/100km(14to20mpg),accordingtoCar and DriverMOREHoldingdownboththeaccel-eratorandbrakeactivatestheoptionalautomaticsLaunchControlmode,whichrevstheengineforthebesttractionandquickestacceleration.POWER PLANT nNinedifferentenginesavailable,from120to270kW,includingn4-and6-cylinderin-linedieselsngasolinein-line6orV8TRANSMISSIONSn6-speedmanualorautomaticnrear-orall-wheeldriveCLAIMED FUEL EFFICIENCY n6.1to10.9L/100kmMOREtoreduceengineloads,bMWplanstointroducemoreelectricaccessorydrives.2008 5-SeriesFor40years,engineersfromthebavarianMotorWorkshaveingeniouslyappliedtech-nologytothepursuitofasinglegoal:superbhandlingandperformance.butnowadays,notevenbMWcanignorecallsforcarsthatconsumeless,emit less,andtreadmoregentlyontheplanet.the company has not announced ahybrid,thoughithaspartneredwithgMandDaimlerChrysler intheirtwo-modehybrid project [see 2008gMCyukontwo-Mode Hybr id]. And now, on i tsrevised5-Seriessportssedans,bMWhasintroducedregenerativebrakingthefirsttimesuchasystemhasbeenusedonanonhybridcar.the companysbrakeEnergyregen-erationsystemgrewoutofanintelligentalternatorcontrolproject shownat lastyearsParisAutoShow.thecoreideaistochangethetimesatwhichthealternatorchargesthebattery.In a conventional car, the alternatorgeneratespowercontinuously,regardlessofother loadson theengine.but in thenew5-Seriescars,itisengagedtogener-atepoweronlywhenthecardecelerates.Atothertimes,whenthecariscruisingoraccelerating, itmerely freewheels.Withthealternatorno longersappingpoweraphenomenonknownasalternatordragtheengineneedstoworkslightlylesshardtomovethecar,cuttingfuelconsumption.thealternatoritselfhasnotchanged;bMWhassimplyinsertedanelectronicallycon-trolledclutchthatengagestoletitchargeonlywhenthecardecelerates.thepowertodriveallthecarselectriccomponentsasmuchas3.5kilowattsinthe average midsize car these daysissuppliedbyasomewhatmorepowerfulbattery.bMWwontreleaseexactfigures,but it does say that it uses glass-mattechnology,whichseparatesthebatterysplateswithsaturatedabsorbentglassboronsilicateratherthantheusualgelorliquidelectrolyte.theacidelectrolyteis held in themicrofibers between lay-ersoflead,improvingitsenergystorageduringfrequentcharge/dischargecycles,comparedwith standard lead-acidbat-teries.thoseordinarybatteriesconvertupto20percentofelectricalenergytoheatduringcharging,againstaslittleas4percentforglass-matdesigns.Alternatordragisfoundinalmosteveryvehiclesoldtoday,soitsimpactmayseeminsignificant.but in theEuropeanuniondrivingcycle,whichisusedtomeasurefuelconsumptionforcarssoldwithinthatmarket,bMWsrevisedalternatorsystemreducedenergyconsumptionbyroughly3percent.nRegenerative braking in a nonhybridtoP:AuDI;LEFt:bMWtop 10 tech cars 2008 R8www.spectrum.ieee.org April2007|IEEESpectrum|NA41ther8,Audisfirstexcursionintosupercarter-ritory,isprojectedtocostroughlyuS$130000whenithitsshowroomsthisyear.Ifthecurrentcropofstartersupercarsleavesyouunder-whelmed,yourshipmaybeabouttocomein.ther8 isstuffedwithadvanced tech-nology,includinganaluminumspaceframe,adirect-injectionmidmountedV8,anda465-watt12-speakersoundsystem.Italsohasshockabsorbersfilledwithfluidwhoseviscosityisvariedelectromagnetically,asintheCadillacXLrandSrX.Allthosetechnologieshaveappearedinothercars,butnotalltogetherinonecar.Andthestylish,two-seatr8hassomethingthatsetsitapartinitscat-egory: light-emittingdiodesfor itsdaytimerunninglights.LEDs of fer many advantagesasautomotivelamps,includinglowpowerandlonglife.theautomotive-lightingcompanyHellaquotes just10WforapairofLEDrunninglights,againstasmuchas150Wforstandard,incandescentones.LEDsalsolastupto 50000hourswhich translates to100yearsofheadlightuseforanaveragecar.Andtheyresmallenoughtogivestyl-istsgreatfreedomoverfront-enddesign:designerscanclusterorscattersingleLEDlampsastheirsketchesrequire.theonlyproblemiscost:upto$1000perpairifyouhavetoreplacethem.thatsroughly 10 t imes as much as the high-intensitydischarge lamps,whichcastabluishlight,usedonupscalecarstoday.Soforthemoment,LEDrunninglightsarelim-itedtojustafewhigh-endAudis:ther8andtheA8,S6,andS8.theracyr8,however,goesitssiblingsonebetterbyalsousingLEDstoilluminateits4.2-liter,309-kilowatt,high-revvingV8,whichisvisiblethroughawindowbehindtheseats.ther8slightsareproducedbyosramoptoSemiconductors, inSanJose.Eachrunninglamphas12separateLEDspotlightsarrangedinasinuouscurveunderthepodcontainingthehighbeamandturnsignal.Eachof theLEDsprovides 18 lumensat140milliamperes.Meanwhile,AudiandLexusarecompetingtobethefirsttouseLEDsasheadlightsinapro-ductioncar.Lexusprobablywillwintherace,asitsLS600htheultraluxurioushybrid-electricflagshipoftheLSlineisexpectedtohitshow-roomsanydaynow.theLexusdesignersstayedwithaconventionalheadlightshapewhichholdshigh-intensitydischargelampsinotherLSmodels(itwasshapedtoevokebaccaratcrystal).butAudipromisestoofferfullLEDheadlampsasanoptionforther8bytheendofthisyear. nlED lights hit the roadPOWER PLANT n2.4-L,2.7-L,or3.5-LTRANSMISSIONn4-or6-speedautomaticn Front-wheeldriveCLAIMED FUEL EFFICIENCYn8.7L/100km(combined,2.4-Lengine)MOREMygigletsyouripCDsontoitsharddrive,butitwontletyoutransfertheMP3filestoanyexternaldevice.Ifyouveboughtanewcarrecently,chancesarethatitcanaccommodatemostoftheentertainmentmedia,formats,andcompres-sionalgorithmsyouprobablynowenjoy:AM,FM,andsatelliteradio;CD;DVD;MP3.butthechallengeofaccessingallthoseoptionsmayhaveleftyouresignedlylisteningtothedroneofnewsradio.Chr ys ler fee ls your pa in. A new,uS$1700option on this yearsSebringsedanbundlesplayersforallthosemedia,plusacellphoneandnavigationsystem,intoasingledash-mountedentertainmentsetupcalledMygig.thesystem,developedwithstereomakerHarman/kardon,featuresasingle,consistentuserinterfacetooper-atethemall.IntheMygigequippedSebring,thediscplayercanplaymusicorshowmov-iestobackseatpassengersfroma7-inchdisplayattherearoftheconsolebetweenthefrontseatsorifthecarisparkedona 6.5-inch in-dash display. themusic,video,andnavigationfunctionscanallbecontrolledbyvoicecommands(inEnglish,Spanish,orFrench)or througha touchscreen.thesystemintegratesbluetoothhands-free mobile call ing, and it canrecordvoicememos.theheartoftheMygigsystemisitsruggedizedharddrivethatholdsnaviga-tiondataandupto1600MP3orWindowsMediaAudiofiles,aswellaseightphotosandupto32address-booknames. It isoneof thefirstcar-basedsystemsthatletsyou ripCD tracks intoMP3 formatandstore themontheharddrive.MP3-savvyreadersmaywonderhowthesystem,withoutanInternetconnection,canfetchtheartist,title,andothertrackinforma-tionforaCD.gladyouasked. Includedwithin thesystems 1gbofsoftware isthegracenote lookupengine to locateinformationforroughlyamillionCDsthatgracenotebelievesNorthAmericanusersmayplay.Chryslerhadntdecidedatpresstimewhethertochargeusersforquarterlyupdatesatthedealer. n2007 Sebringnav system + DVD player + iPod + phone + hard drive = integrationJoHNVoELCkErhaswrittenaboutautomotivetechnologyandothertopicsfor20years.Hecoveredsoftwareandmicroprocessordesignfor IEEE Spectrumfrom1985to1990.DAIMLErCHrySLEr