简介：ThispaperisfocusedonthemodelidentificationofaMicroAirVehicle(MAV)instraightsteadyflightcondition.Theidentificationisbasedoninput-outputdatacollectedfromflighttestsusingbothfrequencyandtimedomaintechniques.Thevehicleisanin-house40cmwingspanairplane.Becauseofthecomplexcoupled,multivariableandnonlineardynamicsoftheaircraft,linearSISOstructuresforboththelateralandlongitudinalmodelsaroundareferencestatewerederived.TheaimoftheidentificationistoprovidemodelsthatcanbeusedinfuturedevelopmentofcontroltechniquesfortheMAV.

简介：Fivekindsof45#steelsampleswithconcavefeaturesonthesurfaceweremanufacturedusingLaserTexturingTechnology(LTT).Optimumdesigntheorywasusedtodesigntheexperiment,andatwo-levelorthogonaltable-L16(215)designwasadopted.Micro-wearandmicro-frictionexperiencedbysampleswithconcavesurfacefeaturesandsampleswithsmoothsurfaceswerecomparedexperimentally.Thewearresistanceofsampleswithconcavesurfacefeatureswasincreasedmost,anddifferentsurfacemorphologieshaddifferenteffectsonfrictionandwearproperties.

简介：Naturalsurfaceswithsuperhydrophobicpropertiesoftenhavemicroorhierarchicalstructures.Inthispaper,thewettingbehavioursofasingledropletonbiomimeticmicrostructuredsurfaceswithdifferentroughnessparametersareinvestigated.Atheoreticalmodelisproposedtostudywettingtransitions.Theresultsoftheoreticalanalysisarecomparedwiththoseofexperimentindicatingthattheproposedmodelcaneffectivelypredictthewettingtransition.Furthermore,anumericalsimulationbasedonthemesoscaleLatticeBoltzmannMethod（LBM）isperformedtostudydynamiccontactangles,contactlines,andlocalvelocityfieldsforthecasethatadropletdisplaysonthemicrostructuredsurface.Asphericalwaterdropletwithrs=15μmfallsdowntoabiomimeticsquare-postpatternedsurfaceundertheforceofgravitywithaninitialvelocityof0.01m·s-1andaninitialverticaldistanceof20μmfromdropletcentretothetopofpots.Inspiteofahigherinitialvelocity,thedropletcanstillstayinaCassiestate;moreover,itreachesanequilibriumstateatt≈17.5ms,whencontactangleis153.16°whichisslightlylowerthanthepredictionofCassie-Baxter’sequationwhichgivesθCB=154.40°.

简介：Themolluskshellmobilizescalciumfromenvironmentforskeletalmineralization.Thisoccursthroughsynthesizingsolidsinsolutioninthepresenceoforganicmoleculesofspecificinteriorregionsoftheconchshell.TheultrastructureandmicrohardnessoftheHemifusustubaconchshelllivingintheHuang/Boseaareaareinvestigatedinthepaper.Itisshownthatthecompositionandmicrostructureofthemolluskshellvaryindifferentpositions.Theprodissoconchshellconsistsonlyofaragonitewiththecrossed-lamellarmicrostructure.WhilethespiralshellandthebodyshelloftheHemifusustubaconchshellarecomposedofonecalcitelayerandseveralaragonitelayers.Thecalcitelayerconsistsofcylindricalgrains,butthearagonitelayersarecrossed-lamellarultrastructureatthreesizescales.Theminimumstructuresize(thethird-orderlamella)isatabout20nm-80nm.Themarginofshellapertureisonlycomposedofcalcitewithcylindricalgrains.ThisnaturaloptimizationoftheshellmicrostructureisintimatelyduetothegrowthoftheOrganicmatrix.Atdifferentpositionsthemicrohardnessofmolluscshellisdifferentduetodifferentcrystalstructuresandcrystalarrangements.Thegrowthprocessofshellsallowsaconstantrenewalofthematerial,thusenablingtheirfunctionaladaptationtoexternalenvironments.

简介：Basedonphotogrammetrytechnology,anovellocalizationmethodofmicro-polishingrobot,whichisrestrictedwithincertainworkingspace,ispresentedinthispaper.Onthebasisofpinholecameramodel,anewmathematicalmodelofvisionlocalizationofautomatedpolishingrobotisestablished.Thevisionlocalizationisbasedonthedistance-constraintsoffeaturepoints.Themethodtosolvethemathematicalmodelisdiscussed.Accordingtothecharacteristicsofgrayimage,anadaptivemethodofautomaticthresholdselectionbasedonconnectedcomponentsispresented.Thecentercoordinateofthefeatureimagepointisresolvedbybilinearinterpolationgraysquareweightedalgorithm.Finally,themathematicalmodeloftestingsystemisverifiedbygloballocalizationtest.Theexperimentalresultsshowthatthevisionlocalizationsysteminworkingspacehashighprecision.

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简介：TheproblemofflappingmotioncontrolofMicroAirVehicles(MAVs)withflappingwingswasstudiedinthispaper.Basedupontheknowledgeofskeletalandmuscularcomponentsofhummingbird,adynamicmodelforflappingwingwasdeveloped.AcontrolschemeinspiredbyhumanmemoryandlearningconceptwasconstructedforwingmotioncontrolofMAVs.Thesalientfeatureoftheproposedcontrolliesinitscapabilitiestoimprovethecontrolperformancebylearningfromexperienceandobservationonitscurrentandpastbehaviors,withouttheneedforsystemdynamicinformation.Furthermore,theoverallcontrolschemehasafairlysimplestructureanddemandslittleonlinecomputations,makingitattractiveforreal-timeimplementationonMAVs.Boththeoreticalanalysisandcomputersimulationconfirmsitseffectiveness.

简介：Overthelastdecade,computationalmethodshavebeenintensivelyappliedtoavarietyofscientificresearchesandengi-neeringdesigns.Althoughthecomputationalfluiddynamics(CFD)methodhasplayedadominantroleinstudyingandsimu-latingtransportphenomenainvolvingfluidflowandheatandmasstransfers,inrecentyears,othernumericalmethodsforthesimulationsatmeso-andmicro-scaleshavealsobeenactivelyappliedtosolvethephysicsofcomplexflowandfluid-interfaceinteractions.Thispaperpresentsareviewofrecentadvancesinmulti-scalecomputationalsimulationofbiomimeticsrelatedfluidflowproblems.Thestate-of-the-artnumericaltechniques,suchaslatticeBoltzmannmethod(LBM),moleculardynamics(MD),andconventionalCFD,appliedtodifferentproblemssuchasfishflow,electro-osmosiseffectofearthwormmotion,andself-cleaninghydrophobicsurface,andthenumericalapproachesareintroduced.Thenewchallengingofmodellingbiomi-meticsproblemsindevelopingthephysicalconditionsofself-cleanhydrophobicsurfacesisdiscussed.

简介：Chip-basedflow-throughPCRimplementsthePCRasacontinuousprocessfornucleicacidanalytics.Thesampleistransportedinawindingchannelthroughtemperaturezonesrequiredfordenaturation,annealingandextension.Mainfieldsofapplicationarethemonitoringofcontinuousprocessesforrapididentificationofcontaminantsandqualitycontrolaswellashighthroughputscreeningofcellsormicroorganisms.Amodulararrangementwithfiveheatingzonesforflow-throughPCRisdiscussedandevaluated.Thespecialheaterarrangementallowstheimplementationofupto40cyclesonthefootprintofamicroscopeslide,whichisplacedontopofa5zonesheatingplate.Liquid/liquidtwophaseflowofPCRreactionmixtureandmineraloilhavebeenappliedtocreateasegmentedflowprocessscheme.Inthatway,thedevelopedsystemmayprovideflow-throughPCRasaunitoperationforthedropletbasedmicrofluidicsplatform.ThesingleuseofdisposabledevicesiscommonlypreferredduetothesensitivityofthePCRprocesstocontaminations.All-glassmicrofluidicchipsanddisposablechipdevices,madefrompolycarbonateasareplicationwithidenticallygeometry,havebeenfabricatedandtested.Forthefirsttime,microchannelgeometrieswithnearlycircularprofiledevelopedbyall-glasstechnologyhavebeentransferredtomassfabricationbyinjectioncompressionmolding.Bothdeviceshavebeensuccessfullyappliedforthedetectionofthetumorsuppressorgenep53.Althoughproductyieldandselectivityoftheamplificationprocessdonotdependonthechipmaterial,awelldefined,reliablesegmentedflowregimecouldonlyberealizedintheall-glasschip.