Leader-follower formation control for a group of ROS-enabled mobile robots

In this brief, the leader-follower formation control of multiple nonholonomic ROS-enabled mobile robots is addressed. First, the formation problem is converted to a trajectory tracking problem and a reference trajectory is generated for each follower. then, a tracking controller from the literature is employed to drive the robots towards their corresponding desired trajectories and thus the formation is achieved. Note that the desired orientation for each follower is selected such that the nonholonomic constraint of the robot is respected and thus, the reference trajectory for each follower will be feasible. In order to assess this control strategy, a ROS-framework is developed to conduct real experiments using four ROS-enabled mobile robots TURTLEBOTs. The main practical drawback of the leader-follower approach is the leader fault. Therefore, we investigate ROS ability to keep the formation in case of a leader failure by modifying the formation and dynamically switching the leader during the experiment.