四旋翼无人机轨迹跟踪与避障控制研究 .pdf

四旋翼无人机轨迹跟踪与避障控制研究

Abstract

Duetoexcellentflexibilityandmaneuverability,thestudyof

quadrotorhasbecomemoreandmorepopularamong

researchers.Withthejointeffortsofmanyengineersand

scholars,thequadrotorUAVhasbeenwidelyusedinmanyfields

suchasmilitaryreconnaissance,policepatrol,agricultural

inspection,entertainmentaerialphotography,andlogistics

transportation.Astheapplicationisgettingwiderandwider,the

controldemandforquadrotor’srapidity,safetyandaccuracyis

stricterandstricter.However,themodelofquadrotoris

underactuated,strongcoupledandnonlinear,whichmakesthe

designofcontrollercomplicating.Forquadrotor,themostcritical

issuesarethecontrloftrajectorytrackingandobstacleavoidance.

Tosolvetheseproblems,thefollowingaspectswillberesearched

inthispaper:

Basedontheanalysisofthequadrotor’sworkingprinciple,

themathematicalmodelofquadrotorwasestablished.Inorder

toestablishtheconnectionbetweentheattitudeloopandthe

positionloop,themathematiclamodelisprocessedbyintroduce

virtualcontrollers,andtheproblemofunderactuationinthe

quadrotorissolved,whichlaysthefoundationforthefollowing

chapters.

Inthetrajectorytrackingofquadrotor,consideringthe

differentdemandsforthequadortor’sattitudeandposition,a

finite-timeterminalslidingmodecontrollerisdesignedforthe

innerloopandaPIDcontrollerisdesignedfortheouterloop.

Besides,Consideringthatthelinearvelocityofquadrotoris

unmeasurableinpractical,afinite-timeobserverisdesignedto

estimatethevelocity.Furthermore,inordertomakethe

transitionprocesssmoother,adifferentialtrackerwasdesigned.

Tofurtherimprovethequadrotor’ssystemperformance,onone

hand,thetraditionalexponentialreac