Abstract: TheINS/VNSintegratednavigationisanimportantautonomousnavigationmethodforlunarrovers.TraditionalINS/VNSintegrated navigationmethodswhichutilizetherelativemotiondifferencesbetweentheinertialandthevisionasmeasurements,usually makeanapproximationbetweentheinertialattitudeerrorsandthemisalignmentangletosimplifytherelativerotation measurementmodel.However,theapproximationerrorcanexceedthemisalignmentanglewhentheheadislarge,which cannotbeignored. Tosolvethisproblem,anewmeasurementerroranalysismethodwaspresentedwhichcanavoidthe approximationintraditionalmethod,andbuildthecorrespondingimprovedmeasurementmodel. Theknowninertialattitudewhichcontainserrorutilizedtogetmoreaccurateerrorexpressionofrelativeinertialrotationquaternion,andreducetheforecasterrorofrelative rotationdifferencebetweentheinertialandthevision.BothoftheMoonbasedsimulationandtheEarth-basedexperiment demonstratethatthepresentedmethodiseffectiveandcanachievehigheraccuraciesofpositionsandattitudesthanthe traditionalone,inwhichthepositionaccuracyhasimproved68%from0.456%to0.143%intheEarth-basedexperiment.

Key words: Inertial/Visionintegratednavigation, Measurementmodel, Lunarrover, Quaternion, Erroranalysis