汽車專業(yè)英語課件：Development of Vehicle Technology -

汽車專業(yè)英語DevelopmentofVehicleTechnologyAmongtherecentvehicleintroductions,fourstandoutasmarkingamajorinnovativeinputtovehicledevelopment.TheMercedesA-classisasignificantadvanceinsmallcarpackagingaswellasbreakingnewgroundinsecondarysafety.Ford’sFocusbringsthecompany’s21stcenturyhard-edgestylingtoitsmostmainstreammodelandalsomarksacompletedmarketrepositioningofaclassofvehiclestartingastheMark1Escorttoavehiclerefinedenoughtocompeteintheneo-luxurysector.TheLandRoverFreelanderbringsthepriceofcomfortable4-wheeldrivevehiclesdowntorealisticlevelsandisabreakthroughinbodyoptionversatility.ProjectThrustSSCpresentstheultimateincompetitionvehiclesandgivesatasteofthetechnologiesrequiredatthelimitsofvehicle-to-groundadhesion.在最近的車輛介紹中，四個(gè)突出點(diǎn)作為標(biāo)志著車輛發(fā)展的主要?jiǎng)?chuàng)新性輸入。在小型汽車包裝以及在二級(jí)安全新突破方面，梅賽德斯A-class是一個(gè)重大的進(jìn)步。福特福特斯將公司的21世紀(jì)鋒刃派風(fēng)格作為其主流模式，同時(shí)標(biāo)志著以Mark1Escort車型為一個(gè)新的市場(chǎng)定位，其精工制作在新的奢侈品行業(yè)具有了足夠的競(jìng)爭(zhēng)力。路虎神行者（TheLandRoverFreelander）使舒適的四輪驅(qū)動(dòng)車的價(jià)位下降到可以被接受的現(xiàn)實(shí)水平，并且是一個(gè)在車身選擇多樣性上的突破。ProjectThrustSSC（SSC項(xiàng)目推動(dòng)）提供了競(jìng)爭(zhēng)車輛的極致，并且實(shí)現(xiàn)了在限制車輛地面的附著力方面的技術(shù)嘗試。8.1MercedesA-classTheworld’spioneeringmanufacturer,andpossiblystillthemostprestigious,hadamomentousyearin1998,andseemedtoemergeastheseniorpartnerinDaimler-Chrysler.Itsearlierattemptstobreakintocompactcarmakinghavealsonowbornefruitintherelaunchedmoose-proofA-classwhichhasbecomepossiblytheclass-leaderincitycars.TherevisedsuspensionsystemissaidtomaketheA-classthesafestcarinitsclass.Themodifiedrearsuspensionnowhasthespecialtierod,incorporatedandallmodelsbenefitfromESP,thecompany’sElectronicStabilityProgramme,Chassiswasalsoslightlylowered,anti-rolltorqueincreasedreartrackextendedslightly,dampers/typesreplaced,suspensionstiffenedandgreaterundersteerbuiltintothehandlingdynamics.ThesandwichfloorconceptallowstheengineanddriveassemblyoftheA-class(asinFig.8-1)tobeshuntedbackunderneaththebodyintheeventofafrontalimpactratherthanpenetratingthepassengercompartment.ThisingeniouslayoutmeansthatthenewMercedesmodelsvirtuallyachievesthehighsafetystandardoftheE-class,evenintheeventofasideimpactthe‘sandwich’conceptofthedoublelayerfloor,providesclearadvantages,becausetheoccupantssitabout20centimetreshigherthaninothercars,withtheresultthattheimpactoccursbelowtheoccupantscell.Fig.8-1MercedesA-classTheA-classcompliesnotonlywiththefutureEUfrontalimpactcrashteststandardbutalsowithstrictsafetyregulationsonsideimpactsintheUSAandtheEuropeanUnion.Intermsofsafety,acarmeasuringonlyabout1000kghasanumberofbasicdisadvantagestoovercome--especiallyifitisbuiltonconventionallines.Thelowvehiclesmass,shortfront-endstructureandlimitedspaceavailableforcrumplezonesarefundamentalhandicapsthatuntilnowhaveleftlittleroominthisvehicleclassforfurtherprogressinvehiclesafety.ThissituationhasbeenrevolutionizedwiththeA-class.Themainaiminthesafetydevelopmentofthecarwastomakemaximumuseoftheshortfrontcrumplezoneinahead-oncollisionandtoclearallcomponentsthatobstructedthecrumplingprocessoutoftheway.Becauseoftherigidstructureofengineandgearbox,theyplaypracticallynopartinthedeformation,andinconventionalcompactcarstheycanbepushedbackinasingleblockthatcanintrudeintotheinteriorandinjuretheoccupants.A-class不僅符合未來歐盟正面沖擊碰撞試驗(yàn)標(biāo)準(zhǔn)，同時(shí)也符合有嚴(yán)格的側(cè)面碰撞安全條例的美國(guó)和歐盟標(biāo)準(zhǔn)。在安全方面，一輛只有約1000公斤重的汽車—尤其是如果它在傳統(tǒng)的生產(chǎn)線上生產(chǎn)出來的，將有一些根本的缺點(diǎn)需要被克服。汽車質(zhì)量小，前后端結(jié)構(gòu)短和有限的碰撞緩沖區(qū)是根本的障礙，直到現(xiàn)在這類汽車在車輛安全取得進(jìn)一步進(jìn)展的可能空間都很小。這種情況在A-class車型上已經(jīng)徹底改變了。Heretheinnovativearrangementofengineandgearboxreducetheriskoftheirformingasingleblockandthereforemakesanessentialcontributiontooccupantsafety.IntheA-class,theengineandgearboxarepositionedatananglepartlyinfrontoftheoccupantcellandpartlyunderneathit,sothatintheeventoffrontalimpacttheycanslidedownwardsratherthanstraightback.Thisispossibleduelargelytothreeunusualfeature:theuniqueinclinedconstructionoftheengineandgearbox,theshapeandinstallationofwhicharespecificallydesignedtoaccordwiththecrashprincipleoftheA-class;thedevelopmentofaframe-typeintegralsupporttoaccommodatetheengineandgearbox,whichinacrashcandisengageattwoofitseightfixingpointstherebyallowingtheengineandgearboxtoslidedownwards;thirdlythedesignofthestablefrontfloorpanel(pedalfloor)asasurfacealongwhichtheengineandgearboxcanslideintheeventofacrash.發(fā)動(dòng)機(jī)和變速箱的創(chuàng)新性布置降低了它們形成單輪滑車的風(fēng)險(xiǎn)，因此對(duì)于車輛安全性做出了不可或缺的貢獻(xiàn)。在A-class車型上，發(fā)動(dòng)機(jī)和變速箱的布置有一定角度的傾斜，使它們一部分在駕駛員室的前面，另一部分在駕駛員室的下面，因此，在出現(xiàn)前端碰撞時(shí)，它們的布置會(huì)產(chǎn)生下滑而不是原來的直接向后。這可能主要是由于三個(gè)不同尋常的特點(diǎn)：獨(dú)特的發(fā)動(dòng)機(jī)和變速箱傾斜結(jié)構(gòu)，其形狀和安裝是專門設(shè)計(jì)以符合A-class車型的碰撞原理；發(fā)動(dòng)機(jī)和變速箱的框架式整體支撐的發(fā)展，在碰撞時(shí)可以是它的八個(gè)固定點(diǎn)中的兩個(gè)脫離結(jié)合，使得發(fā)動(dòng)機(jī)變速箱部分可以產(chǎn)生側(cè)滑；第三個(gè)原因是，穩(wěn)定的前踏板地板的設(shè)計(jì)，當(dāng)碰撞時(shí)，可以作為發(fā)動(dòng)機(jī)和變速箱的滑移表面。ThismaximumpossibledeformationlengthavailableatthefrontendoftheMercedesA-classisduesolelytothefactthattherigidengineandgearboxaredisplacedunderthepassengercellinaserioushead-oncollision.Withoutthiscapacityforevasionandtheabilityoftheengineandgearboxto‘duck’outofthedeformationarea,thefrontendoftheA-classwouldhavetobeabout25cmlongerinordertogivetheoccupantsthesamedegreeofprotection.Thefactthattheshortcrumplezonealsodoesnotsubjecttheoccupantstoseverestressesasaresultofthehigherdecelerationvaluesisduetotheretainingsystemsspeciallymatchedtothefrontendstructure.Otheradvantagesofthenewbodyconcept(asinFig.8-2)arethestraightsidemembers.Theyabsorbhighdeformationforcesrightfromstartofbodydeformationandtherebypermitmuchmorefavorabledecelerationcharacteristicsthanincarsofconventionaldesign.Asaresult,theoccupantsshareinthedecelerationofthevehicleearlierandoveralongerperiod,whichreducesthestressestowhichpassengersaresubjected.Thetriggeringthresholdofseatbelttensionlessandairbagsonthedriverandfrontpassengersidecanalsobemorepreciselydefinedthankstothelongitudinalrigidityofthebodystructure.Thefrontendstructurehasdeformationzonesonthreelevels.TheimpactenergyinthefrontareaoftheA-classiswidelydistributedoverthreeplanes:theframe-typeintegralsupport,whichservestoaccommodatethefrontaxle,engineandgearbox;thestraightsidemembersleadingtothealuminumandsteelfrontmodule;theseconduppersidememberplaneonalevelwiththeheadlamps.Sincemostfrontalimpactsareoffsetcrasheswithunilateralstressingofthefrontendstructure,therearestrongtransverseconnectionsbetweentheimpactzonesdesignedtoensurethatthedeformationareasontheoppositeside,remotefromtheimpact,arealsoinvolved.Thisproducesahomogeneousfrontendstructurewhichwillproveeffectiveinalltypesoffrontalcollision.Thefrontwheelsalsohavearoletoplayinenergyabsorption.TheyformanadditionalloadpathandinanimpactarebracedatthestablenodalpointsofA-pillarandsill.Thiseffectisparticularlyimportantinthefrequentfrontendcrasheswithoverlapononeside-theso-calledoffsetcollisions.M-Bengineershavematchedthestrengthoftheoccupantcelltothehighfrontenddeformationforce.Theraisedflatfloor,whichisweldedfrombelowtoagrid-likesupportstructure,givestheoccupantcellahighdegreeofstabilitysothatitisessentiallynotdeformedeitherinafrontalimpactorinanoffsetcrashwith40or50percentoverlap.Airbagsandbelttensionersandapolystyreneinsertinthefootwell,whichformpartofthestandardequipmentonallMercedescars,completethelistofmeasurestoprotecttheoccupants.Fromtheoutsetthe‘BigversusSmall’aspectwasaprimeconsiderationinthesafetydevelopmentoftheA-class.Inahead-oncollisioninvolvingtwocarsofdifferingmassasuitabledistributionofthedeformationloadbetweenthetwovehiclesmustbeachievedsothatthereisnodangerparticulartotheoccupantsofthesmallercar.ForsometimenowMercedes-Benzhasbeendevelopingitscarsaccordingtothisprincipleandclaimstobethefirsttotestcarsthroughcrashtestsagainstadeformablebarrier.Thistestmethod,whichwillnotbespecifiedforallnewcarsintheEuropeanUnionuntilOctober1998,permitsanespeciallyrealisticsimulationoftypicalaccidentsinvolvingoncomingtraffic,andspecifiesahead-oncollisionat56km/hand40percentoverlapagainstadeformablebarrier.TheA-classpassesthistestevenatanimpactspeedof65km/h,correspondingtoasignificantlyhighstressloading.Compatibilitymeansthatinacollisioninvolvingtwovehiclestheyshouldactivateoneanother’scrumplezonesandbecapableoftransmittingthedeformationloaduniformlytobothbodies.Forthistohappenitisnecessaryforthefrontenddeformationresistanceoflargeandsmallcarstoapproximatetooneanother.Asanexample,intheE-classthefrontendstructureofthisMercedesmodelisconstructedsothatinacrashtheimpactenergyfortheothervehicleisreduce--intelligentsafetyengineeringmeansmutualprotection.Inasmallercar,however,thedesignprincipleisjusttheopposite.BecauseofthelowermassandtheshorterfrontendtheMercedesengineersdesignedtheA-classwithanespeciallyrigidfrontendsothatinanaccidentwithanother,largeroncomingvehicleitcanactivatetheothervehicle’sdeformationzones.Inadditiontomatchingthelevelsofforce,theuniformdistributionofimpactforcesovertheentireheightandwidthofthefrontendplaysaparticularlyimportantrole.OntheA-class,thispurposeisservedbythesecondimpactplanewithitsstabletransverseconnectionstothelowersupportstructure.Eveninafrontalcollisionwithalargecar,theoccupantsofthesmalleronearenotatamajordisadvantageinthiscase.兼容性意味著在兩車相撞過程中，兩輛車應(yīng)該能激活彼此的碰撞緩沖區(qū)，并且能夠均勻地傳輸負(fù)載變形。為此，大型和小型汽車的前端變形阻力應(yīng)該彼此接近。例如，E-class車型中，梅賽德斯這款車的前端結(jié)構(gòu)的模型建立，便于在碰撞中，另一輛車的沖擊能量減小—智能安全工程意味著相互保護(hù)。對(duì)一個(gè)小型汽車而言，設(shè)計(jì)原則是恰恰相反的。由于較低的質(zhì)量和更短的前端，奔馳的工程師們?cè)O(shè)計(jì)A-class車型時(shí)設(shè)計(jì)了一個(gè)特別的剛性前端，所以在與另一輛車的相撞事故中，迎面行駛車輛的體型越大，就越可以較好的激活另一輛車的變形區(qū)。除了水平力的匹配，在車前端的整個(gè)高度和寬度范圍，沖擊力的均勻分布的影響起到一個(gè)特別重要的作用。Thestrengthsofthesandwichconceptofthecararenotconfinedtofront-endcrashes.Theyalsoapplytosideandrearimpactcollisions:inthepreciselevelwherethebodyoftheA-classisatitsstrongest,attheleveloftheload-bearingstructureforthefloor.Theoccupantsareseatedabovethisimpactlevelandarethereforeoptimallyprotect.Theloadbearingstructureofstraightcrossmembersandsidemembersisbetterabletocontainandreducetheimpactenergythaninacarofconventionalbodydesigninwhichtheimpactmostlyoccursabovethefloorstructure.TheshortcrumplezonesatthefrontoftheA-classmakeitnecessarytoactivatethebelttensionedimmediatelyafterthecrash.Asaresult,theoccupantsnotonlytakepartearlierandlongerinthedecelerationofthevehicle,buttheyalsohavealongerdistancefortheircrash-inducedforwardmovement.Theearlierthesafetybeltbuildsupitsrestrainingforce,thelongerthedistanceavailabletothebeltandbelttensionerinwhichtoarresttheforwardmovementoftheoccupants.Inthisway,theforcesunleashedontheoccupantsarelow,despitethemassivedecelerationoftheoccupantcell.Thisalsoservestocompensateforthedesigndisadvantagesofshortdeformationzonesinsmallandcompactcars.TheinnovativerestraintsystemintheA-classincludesfull-sizeairbagsfordriverandfrontpassenger.Theairbagsfittedasstandardhaveavolumeof64and130liters.Theyareoperatedbyanewpropellanttechnologywhichofferscertainadvantageswhenrecycling:thegasgeneratorforthedriver’sairbagisfilledwithanacid-freesolidpropellant,andthepassengerairbagcontainsanenvironmentallysafeliquidgasmixtureofheliumandargon.Thecarhasinertia-reelseatbeltswithbelttensionersonthefrontseats:newlydevelopedcompactbelttensionerscompensateforseatbeltslackandensurethatinacrashtheoccupantsareevenbettertiedtothepassengercellbysnuglyfittingbelts.Thebeltstrapistensionedbysmallsteelballsintheseatbeltretractorswhich,whenthebelttensionalisactivated,aresetinmotionandrotatecountertothebeltstrapshaft.Inthiswaytheyfirststopthebeltstrapandthencoilitbackupathighspeed.Thisdrivesystemhastwooutstandingadvantages:hightensioningcapacityandcompactconstructionoftheseatbeltretractor.Theinertialreelseatbeltsforthefrontseatoccupantsareheight-adjustableinthreestages.Theseatbeltretractorsofthefrontseatbeltsincorporatetorsionbarswhichinacrashareslowlydeformedfromacertainforceupwards,therebyreducingthelockingactionoftheinertialreelseatbelts.Thisreducestheriskofinjurytotheoccupantswhomoreover,thankstotheforcelimiter,cansinkverygentlyintotheairbags.Beltforcelimitersandairbagsarethusdesignedtofunctionaspartofapreciselycoordinatedsystem.ThesideairbagsinthefrontdoorsformpartofthestandardspecificationsoftheA-class.Anewlydevelopedgasgeneratorwithliquidgasfillingisalsousedforthese.M-Balsofitsbelttensionersasstandardontheouterseatsoftherearseatunit.Theseensurethatinacrashrearseatpassengersalsobenefitingoodtimefromthedecelerationofthebodystructure.Theheightadjustmentoftheinterialreelseatsbeltsfunctionsautomaticallyontherearseats.AsontheC-andE-classcars,childseatswhichfoldoutoftherearseatsatthetouchofabuttonareavailableasanoption.慣性卷筒安全帶的前座乘客在三種狀態(tài)下高度可調(diào)。前排座位的安全帶的拉鉤與扭力桿合成一體，使得在碰撞過程中特定的向上的力引起的變形較小，從而減少了慣性卷筒安全帶的鎖定過程。由于對(duì)于作用力的限制，這將減少乘員的風(fēng)險(xiǎn)，乘員可以沉到安全氣囊中。帶力限制器和安全氣囊是設(shè)計(jì)并作為一個(gè)精確地協(xié)調(diào)系統(tǒng)工作的。前門的側(cè)安全氣囊形成了A-class的部分標(biāo)準(zhǔn)規(guī)格規(guī)范。一個(gè)新開發(fā)的氣體發(fā)生器與液態(tài)氣體灌裝也用于這一目的。M-Balso安裝了皮帶張緊裝置作為后座裝置的外圍座椅的標(biāo)準(zhǔn)件。這保證了在碰撞后座乘客也受益于良好的車身結(jié)構(gòu)的減速作用。慣性卷筒安全帶的高度調(diào)整可以在后排座椅上實(shí)現(xiàn)自動(dòng)調(diào)節(jié)。在C-class和E-class車上，兒童安全帶折疊在后排座椅上并且可以通過按鈕進(jìn)行控制，可以被選擇性的安裝。Forthefirst-launchedvehicle,thefrontaxlehasamodifiedMcPhersonsuspensionsystem(asinFig.8-3)withcoilsprings,twin-tubeshockabsorbersandtorsionbarstabilizer.Thesuspensioncomponentsaremountedtogetherwiththerack-and-pinionsteeringgear,engineandgearboxonaframe-typeintegralsupportthatisboltedtothebodyateightpoints.UnliketheoriginalMcPhersonsuspension,theantirollbaroftheA-classdoesnottakepartinwheellocationbutislinkedtothesuspensionstrutviaplasticsuspension:theresultsincludebetterelastokinematicsandincreasedrollingcomfort.Ridecomfortisalsoenhancedbythelow-frictionsuspensionstrutsanddamperguideunits,theTefloncoatingofthefrontbearingofthetorsionbarandthevariousnoise-dampingmeasures.Allwheellocation,suspensionanddampingcomponentshavebeenweight-optimized,suchthatengineershavebeenweight-optimized,suchthatengineershaveachievedanexceptionallygoodbalancebetweenload-bearingabilityandintrinsicweight:theeffectsofthisbalanceonlybecomeevidentinthesumofthecar’smanydetailedsolutions.Anotherconceptualadvantagethatisfeltinthehandingofthecaristhepositionofthesteeringgearinfrontofthecentreofthewheel:thislayoutisonlypossiblebecauseofthesandwichdouble-layerfloorconcept,withtheengineandgearboxlocatedpartlyunderneaththefloorpanel.Steeringresponseisimprovedbythisgeometry.AcompactservopumpforthesteeringoftheA-class,forthefirsttimeinaMercedesisnotmechanicallydrivenbutispoweredbyanelectricmotorwithelectroniccontrol.Pumpcapacitycanbeadjustedpreciselytosuitdemandandtheinstantaneoustrafficsituation.Forexample,whendrivingonthestraight,theelectricmotorrunsatreducedspeedandconsumeslessenergy.Thethree-spokesteeringwheelofthecarisanewdevelopmentandisdesignedinparticulartosatisfytheneedsoflightweightconstruction.The370millimeterdiametersteeringwheelisanaluminumpressure-casting,witharimofpolyurethanefoamcoatedinplasticorleather,dependingontheequipmentlevelandcustomeroption.Thesteeringwheelmaterialcrumplesinacontrolledwayintheeventofhigh-forcecollisionimpact.Thecompanyoptedfortrailingarmsuspensionwithcoilsprings,torsionbarstabilizerandsingle-tubegas-pressureshockabsorbers.Themainadvantageisthattrailingarmsuspensioncanbedesignedwithallitscomponentsunderneaththeloadfloor,sothatitdoesnotencroachontheinteriorspace.Theshockabsorbersandspringsarelocatedinanotherwiseunusedspaceinfrontofthewheelcenter.Withthisgeometry,thesuspensioncomponentssupportthestraightsidemembersinacrash,therebyalsoimprovingoccupantsafety.Thedynamicqualitiesoftherearsuspensionareparticularlyduetospecialtie-boltsthatcontroltheelasticdeformationofthesidemembersandcombinewiththemtoformarectangularlinkagestructure.Changesintheangleofthesidememberandwheelabouttheverticalaxisarecompensatedwithupto75percentefficiency.Thesuspensioncomponents,sidemembers,coilspringsandshockabsorbersaremountedonasuspensionsubframeinasinglecompactblockthatisfixedtothebodyworkonfoursound-proofedrubberbearings,partlywithhydraulicdamping.Therearsuspensionunitismountedwiththeaidoffourverticalassemblybolts.Noneofthesuspensioncomponentsprojectsupwardsabovethelevelofthefloor.Thetechnologyandlayoutofthebrakes,Fig8-4correspondtotheparticularfeaturesoftheA-classdrivesystemandvehicleconcept.Engineersoptedforfloating-caliperdiscbrakesatthefrontanddrumbrakesattherear,becausethiscombinationprovidesoptimalbrakingsafety,stabilityandenduranceforafront-wheeldrivecar,sayM-B.Abrakeboosterandtheanti-lockbrakingsystemprovideaddedsafety.Thedrumbrakesontherearwheelsarecharacterizedbyalightweightconstruction:thesupportingbodyforthewheelbrakecylinderandbrakeshoes,theanchorplateandbrakecylinderaremadeofaluminum.Inordertosatisfythehighsafetyrequirements,thehubsaremadeofsteelandthebrakecylindersofgreycastiron.Anautomaticadjustingsystemcompensatesforbrakepadanddrumwear.TheparkingbrakeintheA-classisoperatedmanually,usingaleverbetweenthefrontseats.Thecontrolcablesaremaintenance-free,sincetheyhaveautomaticlengthadjustment.ESPkeepstheA-classdirectionallystableandreducestheriskofskiddingwhencorneringbyselectivelyapplyingthefrontandrearbrakes.Whiledriving,theESPcomputercomparestheactualbehaviorofthevehiclewiththecalculatedsetpoints.Ifthecarisdeviatingfromthesafe‘idealline’,thesystemrespondsathighspeedwithaspeciallydevelopedlogic,bringingthecarbacktotherighttrackintwoways,firstlybythepreciselydosedbrakingofoneormorewheelsand/orbycontrollingenginetorque.Bythesemethods,ESPcorrectsbothdrivingerrorsandskiddingmovementscausedbyslipperyorwetsurfaces,loosechippingsorotherdifficultroadconditionsthatnormallygivethedriververylittlechancetokeepthecarinlinebysteeringandbrakingaction.TheA-classisthefirstandonlycarinthesubcompactandcompactcarclasstohavesuchaninnovativedrivingsafetysystem.TheElectronicStabilityProgramalsoincludesthecompany’selectronicBrakeAssistSystem.8.2AdvancedFeaturesinFutureVehiclesThisisnotinthemanufacturer’sbestinterests.Somevehiclemanufacturersarevaliantlyattemptingtoimprovecustomersatisfactionatthedealerlevelandthistypeofeffortisbecomingmoreimportanttobrandloyaltyandperceptionsofdealerhonestyasaserviceprovider.Thetaskwillbecomeevermoreimportantinacomplexfuturesociety.EventhoughacentralregisterofallvehiclesmayprovideneededhistoricaldataforvariouspurposesandpermitquickInternetandfaxcontactwiththevehicleowner,thedealer’spersonalcontactwiththecustomerwillremainakeyingredientforoptimumriskreduction.Therearemanylocalissuesthatcouldaffectthedesignoffuturevehicles.Forexample,wheretherearemanyattachedorintegralgarages,shouldthehomebemodifiedorshouldthevehiclesbedesignedtominimizefuelvapor(evaporative)emissionsandexhaustemissions?Theconcerniswiththehealtheffectsofvolatileorganiccompoundsingeneral,benzeneinparticular,andcarbonmonoxide.ArecentstudyofMannindicatedthathomeswithattachedorintegralgarageshadbenzenelevelsthatgrosslyexceededtheapplicablestandards.Inonecase,thebenzeneinaroomabovethegaragewas2.5timestheambientstandard.BenzeneisaGroup1carcinogen(InternationalAgencyforResearchonCancer).Arelatedissueistherequestsbylocalgovernmentagenciestodesignautomobileexhaustsystemstobesuicide-resistantortoeliminatecarbonmonoxideemissions.Theambientairpollutionissuesarealsolocalincharacter,butupto70%oftheambient(environmental)benzeneemissionshavebeenattributedtoroadvehicles.Whatmayseemtobeaminorconstellationoflocalissuestodaymaybecomemuchmoreinthefutureandrequiresomeformofremedy.Mann的最近的一項(xiàng)研究表明，有附帶車庫(kù)和整體車庫(kù)的房屋的苯含量嚴(yán)重超出了適用的標(biāo)準(zhǔn)。在一個(gè)案例中，車庫(kù)上部的房屋內(nèi)的苯是環(huán)境標(biāo)準(zhǔn)的2.5倍。苯是一種致癌物質(zhì)(國(guó)際癌癥研究機(jī)構(gòu))。一個(gè)相關(guān)問題是由當(dāng)?shù)卣畽C(jī)構(gòu)要求設(shè)計(jì)汽車排氣系統(tǒng)來消除自殺性和減少一氧化碳的排放。周圍的空氣污染問題也是具地域性的，但高達(dá)70%的環(huán)境苯排放來源于公路車輛。8.2.1StylingandAerodynamicsStylingchangesinfuturevehiclesareinevitabletoestablishbrandidentityanddemographicsalesappeal.Theaerodynamicconcerns,importantforfuelefficiencyratings,includeswirlingandrotatingvortices,periodicandunsteadyflows,andrelativelyincompressibleairflows.Bothstylingandaerodynamicsdirectlyaffectsafety.Sheetmetalstylingandtheattachedstructuresaffectcrashandcontrolledcrush.Aerodynamics,suchassmoothingoftheundersideofvehicles,couldbeintheformofdamage-resistantshields.However,potentialfuturevehiclesafetyproblemsmayarisefromthetendencytomakelast-minutestylingchangesandeliminateshieldingandskidplatesonacostandsimplicitybasis.Lightweightaluminumspaceframesandbodysegmentswithweldedstampedmetal,extrusions,andcastmaterialhavecrushandenergymanagementcharacteristicsdifferentfromconventionalsteelframes,structures,andbodypanels.Topreventproblems,thiswillrequireconventionaltestingandtime-testedexperience,becauseoftheintrinsicvariationsintheconfigurationsofspaceframes.未來的汽車樣式的變化對(duì)于建立品牌標(biāo)識(shí)和人口銷售吸引力是不可避免的?？諝鈩?dòng)力學(xué)問題，重要的燃料效率評(píng)級(jí)，包括旋轉(zhuǎn)渦流、周期性和不穩(wěn)定的氣流和相對(duì)不可壓縮所引起的氣流。汽車樣式和空氣動(dòng)力學(xué)都會(huì)直接影響安全性。板金樣式和附加的結(jié)構(gòu)影響碰撞和受控制的壓碎。空氣動(dòng)力學(xué)，如平滑車輛的底面，可表現(xiàn)為防破壞盾牌。8.2.2Four-wheelSteeringFour-wheelsteeringsystemsinpassengervehiclesandintrucksmayimprovelow-speedmaneuverability,butwillaffectdrivability.Thesesystemsaregenerallyrear-wheelsteeringsystemsintendedtosupplementthefront-wheelsteeringsystem.Atlowspeedstherearwheelsmoveinadirectionoppositetothatofthefrontwheels.Butathigherspeedstherearwheelsturninthesamedirectionasthefrontwheels.Thismayimprovevehiclestabilityathigherspeedsbyreducingvehicleyaw(rotationalmovement)duringlanechangingpassing,orevasiveactions.Itmayimprovetruckstabilitybyreducingcorrectivesteeringinwindgustsandtrailersway.Atlowspeedsforcarsandtrucks,itshortenstheturningradius.Theremaybehumanproblemsifthedrivercanmakeadjustmenttotherear-wheelsteeringatwill,bycontrolsontheinstrumentpanel.Drivabilityisinfluencedbydegreeofsteeringresponse,thedifferencebetweenneutralandactiverear-wheelsteering,thecharacteristicsofaparticularmodelvehiclecombinedwithitsloadandattachedtrailers,theexternalenvironmentalconditions(ice,snow,rain,windgustsandgrade)andthesophisticationofthedriver.8.2.3DisplayIntegrationThereisalreadyacapabilityofcombiningorintegratingmanydisplaysandcontrolsintoasingleliquidcrystaldisplayofalargeorsmallsize.Asingledisplaysavesspaceandthecostsofdiscretecomponents.Butintermsofthehumandriver,toomanyfunctionscouldaddcomplexity,confusion,andtoomanychoices.

Whatisimportantenoughtodisplay:temperaturecontrol,audiocontrol,time,interiorlighting,speed,fuellevel,theodometer,theestimatedtimeofarrival,hotelinformation,navigationaids,orotherfunctionsandinformation.Whatfunctionsshouldbesharedonthedisplay,suchasonasplitscreen,anoverride,orapermanentoverlay?Shouldanimproperphysicaldistancebetweenanoccupantandtheairbagcontrolunitorinstrumentpanelbedisplayeduntilcorrectedorshouldtheairbagdeploymentuntilitselfmakeanadjustment?Ifanimproperheadpositionisdetectedshouldithavedisplaypriority?Therearemanyquestionsandpossibledesignvariationswhichcouldaffectvehiclesafety.重要的應(yīng)該被顯示信息有:溫度控制、音頻控制、時(shí)間、室內(nèi)照明、速度、燃料等級(jí)、里程表，預(yù)計(jì)到達(dá)時(shí)間，酒店信息、導(dǎo)航、或其他功能。應(yīng)該在顯示器上進(jìn)行信息共享的功能，比如在分割屏幕，一個(gè)功能超越或一個(gè)永久覆蓋？不適當(dāng)在乘員和安全氣囊控制單元或儀表板的物理距離應(yīng)該被顯示直到糾正？或安全氣囊被展開直到本身作了調(diào)整？如果檢測(cè)到不適當(dāng)?shù)念^部位置，是否應(yīng)該顯示優(yōu)先級(jí)?有許多的問題和可能的設(shè)計(jì)變化可能影響車輛安全。8.2.4AdaptiveHeadlightsSmartheadlights,intelligentadaptivefrontlightingsystems,orenhancedlightingsystemsprovideobvioussafetybenefits.Theymayswivelbylinkingsteeringdirectionwithheadlightbeamdirection,haveself-levelingheadlightsifnecessary,mayadjustthepatternofheadlightilluminationontheroadwayintermsofbeamdistance,width,scatter,andsymmetry.TheEuropeanasymmetric‘dippedbeam’lightpattern,providingilluminationtowardtheouteredgeoftheroad,maybechangedtoadaptivesymmetricallightingandstillmeettheregulatoryintentbymeanssuchascutoffsthatlimitthebeampattern.Theremaybebendinglights,eitherbyswivelingturningoneormoreheadlightsorbyincreasingthebrightnessofoneoftheheadlights.Theremaybeweatherlightsthatadjusttofog,rain,snow,orwetroads.Theremaybecitylightsthattakeintoconsiderationthepartialilluminationthatalreadyexistsandthelowspeedofthevehiclesinanurbanarea.Theremaybehighwaylightingwithagreaterbeampatterndistanceandacutofftoreduceglareordazzlet