Vision-based follow-the-leader

We consider the problem of having a group of nonholonomic mobile robots equipped with omnidirectional cameras maintain a desired leader-follower formation. Our approach is to translate the formation control problem from the configuration space into a separate visual servoing task for each follower. We derive the questions of motion of the leader in the image plane of the follower and propose two control schemes for the follower. The first one is based on feedback linearization and is either string stable or leader-to-formation stable, depending on the sensing capabilities of the followers. The second one assumes a kinematic model for the evolution of the leader velocities and combines a Luenberger observer with a linear control law that is locally stable. We present simulation results evaluating our vision-based follow-the-leader control strategies.