Thispaperdescribesacomputationalstudyofthehydrodynamicsofaray-inspiredunderwatervehicleconductedconcurrentlywithexperimentalmeasurements.High-resolutionstereo-videosofthevehicle’sfinmotionsduringsteadyswimmingareobtainedandusedasafoundationfordevelopingahighfidelitygeometricalmodeloftheoscillatoryfin.ACartesiangridbasedimmersedboundarysolverisusedtoexaminetheflowfieldsproducedduetothesecomplexartificialpectoralfinkinematics.SimulationsarecarriedoutatasmallerReynoldsnumberinordertoexaminethehydrodynamicperformanceandunderstandtheresultantwaketopology.Resultsshowthatthevehicle’sfinsexperiencelargespanwiseinflexionofthedistalpartaswellasmoderatechordwisepitchingduringtheoscillatorymotion.Mostthrustforceisgeneratedbythedistalpartofthefin,anditishighlycorrelatedwiththespanwiseinflexion.Twosetsofinter-connectedvortexringsareobservedinthewakerightbehindeachfin.Thosevortexringsinducestrongbackwardflowjetswhicharemainlyresponsibleforthefinthrustgeneration.