A monocular vision-based system for 6D relative robot localization

The objective of this paper is the full 6D relative localization of mobile devices, and direct robot-robot localization in particular. We present a novel relative localization system that consists of two complementary modules: a monocular vision module and a target module with four active or passive markers. The core localization algorithm running on the modules determines the marker positions in the camera image and derives the relative robot pose in 3D space. The system is supported by a prediction mechanism based on regression. The modules are tested successfully in experiments with a quadrotor helicopter as well as on a team of two e-puck robots performing a coverage task. The relative localization system provides accuracies of a few centimeters in position and up to a few degrees in orientation. Furthermore, the system is lightweight, with low complexity and system requirements, which enables its application to a wide range of mobile robot platforms.