深海履帶式集礦機(jī)行走平臺(tái)建模與仿真

深海履帶式集礦機(jī)行走平臺(tái)建模與仿真

atvmechi麻黃,siq標(biāo)準(zhǔn)在deeper同名系統(tǒng)中，a類(lèi)工具使用填海線、預(yù)緊器、旋轉(zhuǎn)器、電子袋和浮游生物1。它是一個(gè)設(shè)計(jì)的深眼疾病，需要良好的曼陀林，可以采取嚴(yán)格的措施，以獲得較高的回報(bào)，但它是不確定的。它是一個(gè)緩慢的，可以采取高效率，作為母針操作和高海拔。本產(chǎn)品采用窄帶吞咽繭內(nèi)顆粒，simulation研究采用窄帶吞咽繭內(nèi)顆粒。ATVisthetoolkitoftheADAMS(AutomaticDynamicAnalysisofMechanicalSystem)thatcanbuildmulti-bodymodelsofmechanicalsystemsandsimulatethefull-motionbehaviorofthemodels.ATVisespeciallydevelopedformodelinganddynamicsimulationoftrackedvehiclemechanicalsystemwithveryhighefficientandshortdevelop&researchperiodatlowcost.1正確的track和trackeForconstructingthemulti-bodymodelofthetrackedvehicle,thetrackedvehicleisdividedintothreemainpartsmulti-bodyhull,lefttrackandrighttrack.Accordingtomultibodytheory,thedynamicmodelsoftrackedvehicleisconstructedbyATVasfollowing。Toachievegoodsimulationperformanceofthemodelthreefactorsofthemodelaremainlydiscussedhere.1.1求解xh-coolomb-3,3,4,4,4,4.3,4.3,..3.3日性別法定strs,..3.3.3日起算數(shù),......................................................3Walkingontheseabedsoftsoil,thetractionoftrackedvehicleisderivedalmostcompletelyfromshearstressofthesoil,insteadoffrictionofthat.AccordingtothetheoryofMOHR-COULOMB(L.L.KaraflathandE.A.Nowatzk,1978),themaximumshearstressTisWherecisthecohesionofsediment,óistheloadstress,φistheinnerfrictionangle.Thus,themaximumtractionsuppliedbysedimentcanbeexpressedasWhereAistheshearareaandWistheweightofthevehicle.1.2非負(fù)擔(dān)重選擇rertratchrex-射線racksitratchsContactforcebetweentracksandsoilisdefinedasimpactforce,andtheimpactforceformulationisWhereq-q0isthepenetrationthattrackedgrouserpenetratesintosoil.Theexponentnshouldbe1.5basedontheHertztheory.Consideringacylinderthatispressedagainstaplate,thepenetratedvolumeisquadraticwiththepenetrationdepth.Testsperformedshowthatanexponentof2-3givesthebestsimulationconvergenceandspeed.1.3ateb等3.3.3index,eth,eth,eth,eth,eth,eth,eth,eth,eth,eth,eth,eth,eth,etiva研磨.us.etin,etiva研磨.us.兩.......................................................AninputfiledescribedthegeometryoftheroadshapeinADAMSisrdf-file.Triangularsegmentsdescribetheroadprofile.TheslopeterrainshapefromsideviewmaylooklikethewidereallineinFigure6.Asetofthreevolumecoordinatevaluesofallthenodesdescribedtheshapeoftheterrainstoredintherdf-fileisshownasfollowing.Firstvolumeisnodenumber,andtherestarecoordinatevalues.Interpolatinginatriangularmeshisaslowprocessinacomputer.Duetothis,ATVwillconverttherdf-fileduringpreprocessingtoarectangularmeshedfile.Allrectanglesareofthesamesize,whichmeansthatforinterpolation,weneedonlytoknowthesizeofeachrectangletoknowinwhichrectangleweshouldinterpolate.Therectangularinterpolationisthenveryfast,asthesecondderivativesoftheroadateachmesharecalculatedduringpreprocessingaswell.Therectangularmeshcanbeseeninthelowerpictureinfigure3.2vehiph隨用量vehiphBasedonthesimulationmodels,thedynamicsimulationresultsundertheconditionsoffourkindsofterrainsareobtainedasfollowing:Animationdisplaysofthetrackedvehiclesimulationundertheconditionofflat,15?slope,2mwidetrenchand0.5mhighobstacle,theresponsecurvesofthedisplacement,velocityandaccelerationofthehullinthedirectionofX(horizontaldirection)andZ(verticaldirection).Theinitialvelocityofthevehicleis0,andthesprocket’sanglevelocity2.58rad/sisgiven.(i.e.,vehicle’svelocityis0.9m/s).Theanalysistosimulationofcrawlingonflatandclimbing15οslopearemainlydiscussedhere.2.1trackingenficiciensre光Accordingtothesimulationcurvesofdisplacementvs.timeindirectionofXcrawlingonflatterrainshowninFigure4theheightofthehull’scenterofmass(CM)descendssuddenlyfrom0.631mto0.616matt=0.3s,thereisabout25cmsinkageoftheCMduringthefirst0.3second.Itismainlybecausethatthestart-upoftrackedvehiclehastodestroytheroadsurfaceforobtainingenoughshearstress.Afterstarting-up,thepositionofthevehicle’sCMtunesback0.635mandbecomesbasicallystableat0.634m.Thoughtheamplitude0.02mofthedisplacementappears,itistoolittletoinfluencethemotioningperformanceoftrackedvehiclewalkingonflat.Fromthesimulationcurveofthevelocityvs.timeindirectionofXontheflatterrainshowninfigure5,itcanbeseenthatthetrackedvehiclereachesitspeekvelocity1.0m/swithin0.4ssuddenly.Afterthat,thevelocityofthetrackedvehiclestartstodropslightlytoastablevaluearound0.9m/s.Thewavewithsmallfluctuatingamplitudeof0.05m/sappearsbutitdoesnotinfluencetheoperationperformance.Thesimulationresultsaresimilartothetestingdatainexperiment(2002,LiLi).Itcanbeseenthatthetrackedvehiclewalksontheflatterraininstablemanner.2.2u3000speat-velope與slope恢復(fù)Asshowninfigure6,thethinreallinepresentsthedisplacementofthevehicle’sCMindirectionofZ,itshorizontalaxisistime(second),verticalheight(meter),whilethewidereallineindicatestheroadsurfaceofslopterrain,bothofitsaxis’sunitaremeter,andthebrokenlineindicatesthetraceofthevehicle’sCM.Accordingtothebrokenlineandthewidereallineinthefigure,itcanbeseenthatclimbingslopeofthetrackedvehicleisverysmooth.Accordingtothefigure7,theclimbingslopeoftrackedvehiclehasthesamestart-upcharacteristicascrawlingonflatshowninfigure3from0to4second,forthevehiclestartingontheflatandcrawlingtheslopeuntilt=4s.Whenthetrackedvehiclebeginstoclimetheslopeatt=4s,thelargerfluctuatingamplitudeof0.25m/sisproducedwhichiseighttimesof0.03m/stestedonflatterrain.Itmainlybecausethatthefrontpartsofthetrackshavetouchedontheslope,whilethebehindpartsofthosearestillonflat,sotheconflictingnormalforcesofdifferentpartsoftrackscausethelargefluctuatingamplitude.Thefrequencyofthevibration6Hzistested,andthevelocityvaluedescendsslowly.Afterclimbingupslopecompletely,thevelocityindirectionofXbecomestablearound0.7m/swithsmallfluctuatingamplitude.WhythevelocityindirectionofXisdropdownwhentrackedvehicleclimbstheslope?Thereareatleastthreereasonstoaccountforthisphenomenon.First,thevelocityofthehullindirectionoftheXequalsV0cos15oafteritclimbinguptheslope,whereV0istheforwardvelocityofthevehicle,soitsvelocityindirectionofXcometobe0.865m/sSecond,theshearstresssupportedbyslopeterrainreduceswhenthevehicleclimbingslope,sothemaximumtraction,accordingtotheformula(2)mentionedabove,reducesaccordingly.Finally,thevehicle’sslippingphenomenonduringclimbingonslopeterrainismoreseriousthanwhathappenedonflat,itcanalsocausereducingofthevelocityindirectionofX.Thoughthevehiclefluctuateswithlargeamplitudeduringclimbingslope,thelargevibrationcan