Decentralized control of leader-follower formations of mobile robots with obstacle avoidance

This paper proposes a decentralized control scheme to guide a leader-follower formation of unicycle-like mobile robots to pass between static obstacles, demanding just one controller per robot. Two approaches are discussed, in terms of obstacle avoidance. One considers the whole formation as a virtual robot, which should avoid obstacles and keep the formation aspect. To do that, the leader robot takes care of goal seeking and obstacle avoidance, while the follower one just keeps the formation as a whole rigid body (rigid formation). In the second approach, the follower robot keeps only its separation from the leader (semi-rigid formation) and avoids obstacles, while the leader one seeks for the goal and avoids obstacles. In each case, the controllers onboard the robots do not share information during navigation (the control strategy is a decentralized one). Experimental results validating the proposal are also presented and discussed.