Multi-robot Formations: One Homography to Rule Them All

The problems of convergence to a desired configuration for a set of robots and leader-following in formation are considered in a framework where the robots have nonholonomic constraints, move in a plane and are observed by a calibrated flying camera, which provides the only sensory information used for the control. We propose a homography-based visual control method only requiring a priori single image of the desired configuration to perform the task. The proposed method consists of an image-based control scheme using the homography induced by the multi-robot system. Therefore, an interesting property is that the whole information regarding the multi-robot system is encapsulated in one single homography. The results show that the system is able to track the leader with the robots in formation despite the leader and camera motion are unknown.