简介：Whilemuchattentionhasbeengiventobio-roboticsinrecentyears,notmuchofthishasbeengiventothechallengingsubjectoflocomotioninslipperyconditions.Thisstudybeginstorectifythisbyproposingabiomimeticapproachtogeneratingthefrictionrequiredtogivesufficientpropulsiveforceonaslipperysubstrate.Wetookinspirationfromasuccessfulbiologicalsolution-thatofapplyinghair-likestructurestothepropulsiveappendages,similartothesetaefoundinnereidpolychaeteslivinginmuddyhabitats.Webeganbyexaminingthemorphologyandthemeanlocomotionparametersofoneofthemostcommonnereids:Nereisdiversicolor.Followingthisstudy,wedesignedandfabricatedaroboticsystemwithappendagesimitatingthebiologicalshapefoundintheworm.Aflexiblecontrolsystemwasdevelopedtoallowmostofthelocomotionparametersobservedintherealwormtobeappliedtotherobot.Experimentsonthreedifferentnaturalsubstratesrangingfromfinesandtogravelshowedthat,whereasaplateattachedtotheappendagegeneratedmostthrustonasmallparticlesubstrate,abundleofartificialsetaeattachedtotheappendagegeneratedmostthrustonalargeparticlesubstrate.Onalltypesofsubstratetested,anappendagewithoutanyattachmentdidsignificantlyworsethanonewith.Thissuggeststhathair-likestructurescanbeadvantageous.

简介：Cellularmetabolismisaverycomplexprocess.Thebiochemicalpathwaysarefundamentalstructuresofbiology.Thesepathwayspossessanumberofregenerationstepswhichfacilitateenergyshuttlingonamassivescale.Thisfacilitatesthebio-chemicalpathwaystosustaintheenergycurrencyofthecells.Thisconcepthasbeenmimickedusingelectroniccircuitcom-ponentsandithasbeenusedtoincreasetheefficiencyofbio-energygeneration.Sixofthecarbohydratebiochemicalpathwayshavebeenchoseninwhichglycolysisistheprinciplepathway.Allthesixpathwaysareinterrelatedandcoordinatedinacom-plexmanner.Mimiccircuitshavebeendesignedforallthesixbiochemicalpathways.Thecomponentsofthemetabolicpath-wayssuchasenzymes,cofactorsetc.,aresubstitutedbyappropriateelectroniccircuitcomponents.Enzymesarerelatedtothegainoftransistorsbythebonddissociationenergiesofenzyme-substratemoleculesunderconsideration.Cofactorsandcoen-zymesarerepresentedbyswitchesandcapacitorsrespectively.Resistorsareusedforproperorientationofthecircuits.Theenergyobtainedfromthecurrentmethodsemployedforthedecompositionoforganicmatterisusedtotriggerthemimiccir-cuits.Asimilarenergyshuttleisobservedinthemimiccircuitsandthepercentageriseforeachcycleofcircuitfunctioningisfoundtobe78.90.Thetheoreticalcalculationshavebeenmadeusingasampleofdomesticwasteweighing1.182kg.Thecalculationsarrivedatfinallyspeakoftheefficiencyofthenovelmethodologyemployed.

简介：Thepaperpresentsamulti-scalemodellingapproachforsimulatingmacromoleculesinfluidflows.Macromoleculetransportatlownumberdensitiesisfrequentlyencounteredinbiomedicaldevices,suchasseparators,detectionandanalysissystems.Accuratemodellingofthisprocessischallengingduetothewiderangeofphysicalscalesinvolved.Thecontinuumapproachisnotvalidforlowsoluteconcentrations,butthelargetimescalesofthefluidflowmakepurelymolecularsimulationsprohibitivelyexpensive.Apromisingmulti-scalemodellingstrategyisprovidedbythemeta-modellingapproachconsideredinthispaper.Meta-modelsarebasedonthecoupledsolutionoffluidflowequationsandequationsofmotionforasimplifiedmechanicalmodelofmacromolecules.Theapproachenablessimulationofindividualmacromoleculesatmacroscopictimescales.Meta-modelsoftenrelyonparticle-correctoralgorithms,whichimposelengthconstraintsonthemechanicalmodel.Lackofrobustnessoftheparticle-correctoralgorithmemployedcanleadtoslowconvergenceandnumericalinstability.AnewFAstLinearCOrrector(FALCO)algorithmisintroducedinthispaper,whichsignificantlyimprovescomputationalefficiencyincomparisonwiththewidelyusedSHAKEalgorithm.ValidationofthenewparticlecorrectoragainstasimpleanalyticsolutionisperformedandimprovedconvergenceisdemonstratedforssDNAmotioninalid-drivenmicro-cavity.

简介：

简介：Robotlocomotionisanactiveresearcharea.Inthispaperwefocusonthelocomotionofquadrupedrobots.Aneffectivewalkinggaitofquadrupedrobotsismainlyconcernedwithtwokeyaspects,namelyspeedandstability.Thelargesearchspaceofpotentialparametersettingsforlegjointsmeansthathandtuningisnotfeasibleingeneral.Asaresultwalkingparametersaretypicallydeterminedusingmachinelearningtechniques.Amajorshortcomingofusingmachinelearningtechniquesisthesignificantwearandtearofrobotssincemanyparametercombinationsneedtobeevaluatedbeforeanoptimalsolutionisfound.Thispaperproposesadirectwalkinggaitlearningapproach,whichisspecificallydesignedtoreducewearandtearofrobotmotors,jointsandotherhardware.Inessenceweprovideaneffectivelearningmechanismthatleadstoasolutioninafasterconvergencetimethanpreviousalgorithms.Theresultsdemonstratethatthenewlearningalgorithmobtainsafasterconver-gencetothebestsolutionsinashortrun.Thisapproachissignificantinobtainingfasterwalkinggaitswhichwillbeusefulforawiderangeofapplicationswherespeedandstabilityareimportant.Futureworkwillextendourmethodssothatthefasterconvergencealgorithmcanbeappliedtoatwoleggedhumanoidandleadtolesswearandtearwhilststilldevelopingafastandstablegait.

简介：Anewbionicapproachispresentedtofindtheoptimaltopologiesofastructurewithtension-onlyorcompression-onlymaterialbasedonboneremodellingtheory.Bytraditionalmethods,thecomputationalcostoftopologyoptimizationofthestructureishighduetomaterialnonlinearity.Toimprovetheefficiencyofoptimization,thereference-intervalwithmaterial-replacementmethodispresented.Inthemethod,firstly,theoptimizationprocessofastructureisconsideredasboneremodellingprocessunderthesameloadingconditions.AreferenceintervalofStrainEnergyDensity(SED),correspondingtothedeadzoneorlazyzoneinbonemechanics,isadoptedtocontroltheupdateofthedesignvariables.Secondly,amaterial-replacementschemeisusedtosimplifytheFiniteElementAnalysis(FEA)ofstructureinoptimization.Intheoperationofmaterial-replacement,theoriginaltension-onlyorcompression-onlymaterialindesigndomainisreplacedwithanewisotropicmaterialandtheEffectiveStrainEnergyDensity(ESED)ofeachelementcanbeobtained.Finally,theupdateofdesignvariablesisdeterminedbycomparingthelocalESEDandthecurrentreferenceintervalofSED,e.g.,theincrementofarelativedensityisnonzeroifthelocalESEDisoutofthecurrentreferenceinterval.Numericalresultsvalidatethemethod.

简介：MultipleUninhabitedAerialVehicles(multi-UAVs)coordinatedtrajectoryreplanningisoneofthemostcomplicatedglobaloptimumproblemsinmulti-UAVscoordinatedcontrol.Basedontheconstructionofthebasicmodelofmulti-UAVscoordinatedtrajectoryreplanning,whichincludesproblemdescription,threatmodeling,constraintconditions,coordinatedfunctionandcoordinationmechanism,anovelMax-MinadaptiveAntColonyOptimization(ACO)approachispresentedindetail.Inviewofthecharacteristicsofmulti-UAVscoordinatedtrajectoryreplanningindynamicanduncertainenvironments,theminimumandmaximumpheromonetrailsinACOaresettoenhancethesearchingcapability,andthepointpheromoneisadoptedtoachievethecollisionavoidancebetweenUAVsatthetrajectoryplannerlayer.Consideringthesimultaneousarrivalandtheair-spacecollisionavoidance,anEstimatedTimeofArrival(ETA)isdecidedfirst.ThenthetrajectoryandflightvelocityofeachUAVaredetermined.Simulationexperimentsareperformedunderthecomplicatedcombatingenvironmentcontainingsomestaticthreatsandpopupthreats.Theresultsdemonstratethefeasibilityandtheeffectivenessoftheproposedapproach.