Uncertainty and accuracy of vision-based tracking concerning stereophotogrammetry and noise-floor tests

Abstract

This work proposes a systematic assessment of stereophotogrammetry and noise-floor tests to characterize and quantify the uncertainty and accuracy of a vision-based tracking system. Two stereophotogrammetry sets withdifferentconfigurations,i.e.,someimagesaredesignedandtheirsensitivityisquantifiedbasedonseveral assessments.Thefirstassessmentevaluatestheimagecoordinates,stereoangleandreconstructionerrors resultingfromthestereophotogrammetryprocedure,andthesecondassessmentexpressestheuncertainty fromthevarianceandbiaserrorsmeasuredfromthenoise-floortest.Thesetwoassessmentsquantifythe uncertainty,whiletheaccuracyofthevision-basedtrackingsystemisassessedfromthreequasi-static testsonasmall-scaledspecimen.Thedifferenceineachstereophotogrammetrysetandconfiguration,as indicatedbythestereophotogrammetryandnoise-floorassessment,leadstoasignificantresulthatthefirst stereophotogrammetrysetmeasurestheRMSEof3.6mmwhilethesecondsetidentifiesonly1.6mmof RMSE.Theresultsofthisworkrecommendacarefulandsystematicassessmentofstereophotogrammetry andnoise-floortestresultstoquantifytheuncertaintybeforetherealtesttoachieveahighdisplacement accuracyofthevision-basedtrackingsystem