資源描述：
《baja動(dòng)力總成設(shè)計(jì)畢業(yè)課程設(shè)計(jì)外文文獻(xiàn)翻譯、中英文翻譯、外文翻譯》由會(huì)員上傳分享，免費(fèi)在線閱讀，更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫(kù)。
1、DesignofanSAEBajaRacingOff-RoadVehiclePowertrainIwasfortunateenoughtobeabletoleadpowertraindesignontheBajateamfortwoyearsinarow，whichallowedmetonotonlytesttheoriesandmodifythem，butalsotolearnfrommistakes.Abriefreviewofthe2014carpowertraindesignisinorder，asitinformsmanyofthedesigndecisionsmadeforthe2
2、015Bajacar.The2014AkronBajaCar(ZB14)usesaComet780seriesCVTcoupledtoatwostagechainreductiontocoupletheEnginetothe22inchdiametertires.Thelayoutofthischainreductionwasdesignedwithtwothingsinmind.First,therewasadesiretoseetheaccelerationbenefitsofraisingtheEnginehigherinthecar，thusraisingthecenterofmass
3、ofthecarandthesubsequentlongitudinalweighttransferduringacceleration.Thisincreaseinlongitudinalweighttransferwouldtheoreticallyprovidemoretractiveabilityforthereartiresduringanaccelerationrun.Thesecondobjectiveofthechainlayoutwastoreducethewheelbaseasmuchaspossible.Wcfoundthattherewasnottoomuchbenef
4、itgainedbytheincreasedheightofthecenterofgravityduringacceleration.Inaddition，thenegativeeffectthishighercenterofgravityhadonlateralhandlingandrollovercompletelyoutweighsanypositiveaccelerationeffectsgainedbyaraisedengine.Ideally,thebottomoftheengineshouldbeplacedaslowaspossibleforthebesthandlingcar
5、.Theshorterwheelbaseaccomplishedwiththeuniquepackingofthedrivelinedidhelpwithnavigatingtightobstaclesinmaneuverability,asdemonstratedbyour22ndfinishinmaneuverabilityatthe2014competitioninIllinois(Seeresultscompilationinappendixforfullplacementdetails).Thiscarwasalsousedtoverifytheeffectivenessoftheg
6、earreductionratiocalculatedfromtheorythatwillpresentedlaterinthisreport.Fromthistestingitwasfoundthatonlyaslightmodificationtotheoriginallycalculatedgearratiowasnecessarytoreachawellperformingvehicle.ChainDriveversusSpurGearDriveBeforethedesignofthepowertrainforthe2015AkronZipsBajaRacecar(ZB15)could
7、begin,animportantdecisionneededtobemade.ThisdecisionwaswhethertouseanuncoveredchainreductionsimilartoZB14ortouseanenclosed，continuously-lubricatedspurgearbox.Bothselectionshavestrengthsandweaknessesan
