EnglishforUnmannedaerialvehicle無人機專業(yè)英語第三部分第四部分慣性測量單元慣性導(dǎo)航系統(tǒng)的詳細(xì)說明Unit5Inertialnavigationsystem——Inertialnavigationsystemsindetail、InertialmeasurementunitInertial[?'n???(?)l]NavigationSystem

(INS)

慣性導(dǎo)航系統(tǒng)Accelerometers[?k,sel?'r?m?t?]

加速度計Gyroscopes['d?a?r?sk??p]

陀螺儀Magnetometers[,m?gn?'t?m?t?]

傳感器deadreckoning

['rek(?)n??]

航位推算法Orientation[,?:r??n'te??(?)n]

方向Submarines['s?bm?,rin]

潛艇IMU=inertialmeasurement['me??m(?)nt]units

慣性測量單元NewWords&Phrasesorthogonal[?:'θ?g(?)n(?)l]

正交的tactical['t?kt?k(?)l]

戰(zhàn)術(shù)的Strategic[str?'ti:d??k]

戰(zhàn)略的MEMS=microelectromechanical['ma?kr??-?,lektr??m?'k?n?k(?)l]systems

微機電系統(tǒng)Initialization[?,n???la?'ze???n]

初始化jamming

['d??m??]

干擾Deception[d?'sep?(?)n]

欺騙Constraint[k?n'stre?nt]

強制NewWords&PhrasesIntegrate['?nt?gre?t]集成Kinematic[,k?n?'m?t?k]運動學(xué)Yields[ji:ld]生產(chǎn)Drift[dr?ft]漂移Accumulate[?'kju:mj?le?t]積累nautical['n??t?k(?)l]航海的Inaccuracies[?n??kj?r?s?]誤差numerical[nju:'mer?k(?)l]adj.integration[?nt?'gre??(?)n]數(shù)值積分pedometers[p??d?m?t?]計步器NewWords&Phrasespitch[p?t?]

俯仰Yaw[j?:]

偏航roll[r??l]

滾轉(zhuǎn)Cockpit['k?kp?t]

駕駛艙Inertialguidance['ga?d(?)ns]

慣性制導(dǎo)Schuler[?u:l?]tuning['tju?n??]

舒勒調(diào)諧Magnetometer[,m?gn?'t?m?t?]

磁強計UAV=unmannedaerial['e?r??l]vehicles

[?vi??k(?)lz]

無人機Landers['l?nd?]n.著陸器NewWords&PhrasesCommercial[k?'m?:?(?)l]商業(yè)UGV=UnmannedGroundVehicle無人地面車UUV=UnmannedUnderwater[?nd?'w?：t?]Vehicle無人潛水器Inclination[?nkl?'ne??(?)n]傾角Collision[k?'l??(?)n]碰撞Wearable['we?r?bl]可穿戴proliferation[pro,l?f?'re??n]增殖Strap[str?p]DownInertialSystem捷聯(lián)慣性系統(tǒng)Transponder[tr?n'sp?nd?]應(yīng)答機NewWords&PhrasesINScontain

InertialMeasurementUnits

(IMUs)whichhaveangularandlinearaccelerometers(forchangesinposition);someIMUsincludeagyroscopicelement(formaintaininganabsoluteangularreference).AngularaccelerometersmeasurehowtheUAVisrotatinginspace.Generally,thereisatleastonesensorforeachofthethreeaxes:pitch(noseupanddown),yaw(noseleftandright)androll(clockwiseorcounter-clockwisefromthecockpit).角加速度計用于測量無人機在空間中的旋轉(zhuǎn)。一般來說，這三個軸至少有一個傳感器：俯仰(上下)、偏航(左右)和滾轉(zhuǎn)(從駕駛艙看是順時針方向或逆時針方向)。Part3---InertialnavigationsystemsindetailLinearaccelerometersmeasurenon-gravitationalaccelerations

ofthevehicle.Sinceitcanmoveinthreeaxes(up&down,left&right,forward&back),thereisalinearaccelerometerforeachaxis.Acomputercontinuallycalculatesthevehicle'scurrentposition.First,foreachofthesix

degreesoffreedom

(x,y,zandθx,θy

andθz),itintegratesovertimethesensedacceleration,togetherwithanestimateofgravity,tocalculatethecurrentvelocity.Thenitintegratesthevelocitytocalculatethecurrentposition.計算機不斷計算飛機的當(dāng)前位置。首先，對于六個自由度(x，y，z和θx，θy和θz)，隨著時間的推移，它將加速度進(jìn)行積分。加上重力的估計，用來計算當(dāng)前的速度。然后速度再積分來計算當(dāng)前位置。Part3---InertialnavigationsystemsindetailInertialguidanceisdifficulttoworkwithoutcomputers.Thedesiretouseinertialguidanceinthe

Minutemanmissile

and

ProjectApollo

droveearlyattemptstominiaturizecomputers.Inertialguidancesystemsarenowusuallycombinedwith

satellitenavigationsystems

throughadigitalfilteringsystem.Theinertialsystemprovidesshorttermdata,whilethesatellitesystemcorrectsaccumulatederrorsoftheinertialsystem.慣性導(dǎo)航系統(tǒng)通常通過數(shù)字濾波系統(tǒng)與衛(wèi)星導(dǎo)航系統(tǒng)相結(jié)合。慣性系統(tǒng)提供短期數(shù)據(jù)，而衛(wèi)星系統(tǒng)來修正慣性系統(tǒng)的累積誤差。Part3---InertialnavigationsystemsindetailAninertialguidancesystemthatwilloperatenearthesurfaceoftheearthmustincorporate

Schulertuning

sothatitsplatformwillcontinuepointingtowardsthecenteroftheearthasavehiclemovesfromplacetoplace.Part3---InertialnavigationsystemsindetailAn

inertialmeasurementunit

(IMU)isanelectronicdevicethatmeasuresandreportsabody's

specificforce,angularrate,andsometimesthemagneticfieldsurroundingthebody,usingacombinationof

accelerometers

and

gyroscopes,sometimesalso

magnetometers.IMUsaretypicallyusedtomaneuver

aircraft,including

unmannedaerialvehicles

(UAVs),amongmanyothers,and

spacecraft,including

satellites

and

landers.RecentdevelopmentsallowfortheproductionofIMU-enabled

GPS

devices.AnIMUallowsaGPSreceivertoworkwhenGPS-signalsareunavailable,suchasintunnels,insidebuildings,orwhenelectronicinterferenceispresent.

Part4---InertialmeasurementunitOperationalprinciplesAninertialmeasurementunitworksbydetectinglinearaccelerationusingoneormore

accelerometers

androtationalrateusingoneormore

gyroscopes.Somealsoincludea

magnetometer

whichiscommonlyusedasaheadingreference.慣性測量單元通過使用一個或多個加速度計來測量線性加速度，使用一個或多個陀螺儀測量旋轉(zhuǎn)速度，其中還包括一個用做航向基準(zhǔn)的普通磁強計，Part4---InertialmeasurementunitOperationalprinciplesAsshowninFig4-1,typicalconfigurationscontainoneaccelerometer,gyro,andmagnetometerperaxisforeachofthethreevehicleaxes:

pitch,rollandyaw.Part4---InertialmeasurementunitFig.4-1IMUswork,inpart,bydetectingchangesinpitch,roll,andyawUsesIMUsareoftenincorporatedinto

InertialNavigationSystems

whichutilizetherawIMUmeasurementstocalculate

attitude,angularrates,linearvelocityandpositionrelativetoaglobalreferenceframe.TheIMUequippedINSformsthebackboneforthenavigationandcontrolofmanycommercialandmilitaryvehiclessuchasmannedaircraft,missiles,ships,submarines,andsatellites.Part4---InertialmeasurementunitUsesTheyarealsoessentialcomponentsintheguidanceandcontrolofunmannedsystemssuchas

UAVs,

UGVs,and

UUVs.SimplerversionsofINSstermed

AttitudeandHeadingReferenceSystems

utilizeIMUstocalculatevehicleattitudewithheadingrelativetomagneticnorth.ThedatacollectedfromtheIMU'ssensorsallowsacomputertodetermineacraft'sposition,usingamethodknownas

deadreckoning.Part4---InertialmeasurementunitUsesInlandvehicles,anIMUcanbeintegratedintoGPSbased

automotivenavigationsystems

or

vehicletrackingsystems,givingthesystemadeadreckoningcapabilityandtheabilitytogatherasmuchaccuratedataaspossibleaboutthevehicle'scurrentspeed,turnrate,heading,inclinationandacceleration,incombinationwiththevehicle's

wheelspeedsensor

outputand,ifavailable,reversegearsignal,forpurposessuchasbetter

trafficcollision

analysis.Part4---Inertialmeasurementunit在陸地車輛中，IMU可以集成到基于GPS的汽車導(dǎo)航系統(tǒng)或車輛跟蹤系統(tǒng)中，使系統(tǒng)具有航跡推算能力和收集盡可能多的準(zhǔn)確數(shù)據(jù)的能力。包括車輛當(dāng)前的速度、轉(zhuǎn)彎速率、航向、傾角和加速度等數(shù)據(jù)，并結(jié)合車輛的車輪速度傳感器輸出。并在可用的情況下結(jié)合反向齒輪信號，用于更好的交通碰撞分析。Part4---InertialmeasurementunitUsesBesidesnavigationalpurposes,IMUsserveasorientationsensorsinmanyconsumerproducts.AlmostallsmartphonesandtabletscontainIMUsasorientationsensors.FitnesstrackersandotherwearablesmayalsoincludeIMUstomeasuremotion.SomegamingsystemssuchastheremotecontrolsfortheNintendoWiiuseIMUstomeasuremotion.Part4---InertialmeasurementunitUsesLowcostIMUshaveenabledtheproliferationoftheconsumerdroneindustry.Theyarealsofrequentlyusedforsportstechnology(techniquetraining),andanimationapplications.Theyareacompetingtechnologyforusein

motioncapture

technology.AnIMUisattheheartofthebalancingtechnologyusedinthe

SegwayPersonalTransporter.Part4---InertialmeasurementunitInnavigationInanavigationsystem,thedatareportedbytheIMUisfedintoaprocessorwhichcalculatesattitude,velocityandposition.

AtypicalimplementationreferredtoasaStrapDownInertialSystemintegratesangularratefromthegyroscopetocalculateangularposition.在導(dǎo)航系統(tǒng)中，IMU報告的數(shù)據(jù)被輸入處理器，處理器計算姿態(tài)、速度和位置。一種典型的被稱為捷聯(lián)慣性系統(tǒng)，成功實現(xiàn)了從陀螺儀中提取角速度用來計算角位移。Part4---InertialmeasurementunitInnavigationThisisfusedwiththegravityvectormeasuredbytheaccelerometersina

Kalmanfilter

toestimateattitude.Theattitudeestimateisusedtotransformaccelerationmeasurementsintoaninertialreferenceframe(hencetheterminertialnavigation)wheretheyareintegratedoncetogetlinearvelocity,andtwicetogetlinearposition.

這融合了加速度計測量的重力矢量，用卡爾曼濾波來估計姿態(tài)。姿態(tài)估計用于將加速度測量轉(zhuǎn)換為慣性參考坐標(biāo)系（所以叫慣性導(dǎo)航），它們一次積分獲得線速度，兩次積分再得到線位移。Part4---InertialmeasurementunitInnavigationForexample,ifanIMUinstalledinan

aeroplane

movingalongacertaindirectionvectorweretomeasureaplane'saccelerationas5m/sec^2for1sec,thenafterthat1sectheguidancecomputerwoulddeducethattheplanemustbetravelingat5m/secandmustbe2.5mfromitsinitialposition(assumingv0=0andknownstartingpositioncoordinatesx0,y0,z0).Part4---InertialmeasurementunitInnavigationIfcombinedwithamechanicalpapermaporadigitalmaparchive(systemswhoseoutputisgenerallyknownasa

movingmapdisplay

sincetheguidancesystempositionoutputisoftentakenasthereferencepoint,resultinginamovingmap),theguidancesystemcouldusethismethodtoshowapilotwheretheplaneislocatedgeographicallyinacertainmoment,aswitha

GPS

navigationsystem—butwithouttheneedtocommunicatewithorreceivecommunicationfromanyoutsidecomponents,suchassatellitesorlandradiotransponders,thoughexternalsourcesarestillusedinordertocorrectdrifterrors,andsincethepositionupdatefrequencyallowedbyinertialnavigationsystemscanbehigherthevehiclemotiononthemapdisplaycanbeperceivedassmoother.Thismethodofnavigationiscalled

deadreckoning.Part4---InertialmeasurementunitInnavigationOneoftheearliestunitswasdesignedandbuiltby

FordInstrumentCompany

fortheUSAFtohelpaircraftnavigateinflightwithoutanyinputfromoutsidetheaircraft.Calledthe

Ground-PositionIndicator

oncethepilotenteredintheaircraftlongitudeandlatitudeattakeoff,theunitwouldsho