Experimental Comparison of Fiducial Markers for Pose Estimation

Accurate localization is crucial for the autonomous navigation and control of Unmanned Aircraft Systems (UAS). In most applications, localization is provided from a Global Navigation Satellite System like GPS and Galileo or more recently from Visual Odometry, Visual-Inertial Odometry, and Simultaneous Localization and Mapping methods. In many cases though, especially when precise maneuvers are required, fiducial markers are used. Fiducial markers are able to provide accurate localization data and have been used in many applications where reliable pose measurements are needed for specific objects or locations. This paper presents an experimental comparison of four different open-source fiducial markers that are widely used in UAS applications (ARTag, AprilTag, ArUco, and STag). The fiducial markers are evaluated based on their localization capabilities as well as their computational efficiency. To facilitate the comparison, a ROS package for the STag marker is developed and publicly released.