Wing-surface reconstruction of a Lanner-falcon in free flapping flight with multiple cameras

Abstract

This paper presents a way to reconstruct the upper and lower surface of a curved and textured Lanner-falcon wing in flapping flight. A stereo camera system was used to take images of a free-flying bird in a wind-tunnel. The usage of two cameras allows for the finding of correspondences of sought-after surface points in both cameras. Further more, three dimensional coordinates can be triangulated. To get camera points, which belong together, a disparity map is calculated with the help of a Semi-Global Block Matching algorithm. A reduction of the complexity is achieved by rectifying the camera-images on the basis of the epipolar geometry. The analysis shows that the surface structure of a Lanner-falcon and the motion during a specified time-series can be reconstructed with sufficient accuracy.