摘要
Tochangeflightdirection,flyinganimalsmodulateaerodynamicforceeitherrelativetotheirbodiestogeneratetorqueaboutthecenterofmass,orrelativetotheflightpathtoproducecentripetalforcethatcurvesthetrajectory.Inemployingthelatter,thedirectionofaerodynamicforceremainsfixedinthebodyframeandrotationsofthebodyredirecttheforce.Whilebothaforementionedtechniquesareessentialforflight,itiscriticaltoinvestigatehowananimalbalancesthetwotoachieveaeriallocomotion.Here,wemeasuredwingandbodykinematicsofcicada(Tibicenlinnei)infreeflight,includingflightperiodsofbothlittleandsubstantialbodyreorientations.Itisfoundthatcicadasemployacommonforcevectoringtechniquetoexecutealltheseflights.Weshowthatthedirectionofthehalf-strokeaveragedaerodynamicforcerelativetothebodyisindependentofthebodyorientation,varyinginarangeofmerely20deg.Despitedirectionallimitationoftheaerodynamicforce,pitchandrolltorquearegeneratedbyalteringwingangleofattackanditsmeanpositionrelativetothecenterofmass.Thisresultsinbodyrotationswhichredirectthewingforceintheglobalframeandconsequentlychangetheflighttrajectory.
出版日期
2016年02月12日(中国期刊网平台首次上网日期,不代表论文的发表时间)