Abstract

Using fiducial markers ensures reliable detection andidentification of planar features in images. Fiducials areused in a wide range of applications, especially when a re-liable visual reference is needed, e.g., to track the camerain cluttered or textureless environments. A marker designedfor such applications must be robust to partial occlusions, varying distances and angles of view, and fast camera mo-tions. In this paper, we present a robust, highly accuratefiducial system, whose markers consist of concentric rings,along with its theoretical foundations. Relying on projectiveproperties, it allows to robustly localize the imaged markerand to accurately detect the position of the image of the (common) circle center. We demonstrate that our system can detect and accurately localize these circular fiducials under very challenging conditions and the experimental results reveal that it outperforms other recent fiducial systems.