A Novel Decentralized Leader–Follower Control Scheme for Centroid and Formation Tracking

This article deals with the centroid and formation control problem of multiagent robotic systems. The proposed solution is based on a leader–follower scheme, where only a subset of agents, i.e., the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">leaders</i>, knows the desired trajectories for the centroid and the formation of the system, while the other agents, i.e., the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">followers</i>, are required to estimate them through a dynamic consensus scheme. The leaders perform trajectory scaling in order to cope with the velocity limits of the single robots. Once the trajectories for the centroid and the formation are estimated, each agent can compute its own reference trajectory and a local control loop is designed to track it. An approach to mapping the velocity constraints of each agent to the velocity limits at the task level is developed. Then, a trajectory-scaling algorithm is adopted to ensure velocity constraint fulfillment. The stability and performance properties are rigorously analyzed under two different assumptions about the planned trajectories. Finally, both simulation and experiments are run on the Robotarium platform to show the effectiveness of the approach and the effect of parameter tuning on the achieved performance.