A local sensor based leader-follower flocking system

This paper presents a leader-follower flocking system based on local sensor information. In this system, the leader robot knows global trajectory, tries to track the global trajectory, and has the ability to avoid collisions. The follower robots do not know global trajectory. They only use local sensors to acquire relative information between neighbors. In this paper they use a laser scanner to obtain relative distances and relative angles between neighbors. By using local information, the follower robots maintain the distances between their neighbors and avoid collisions with their neighbors. We prove that such a leader-follower flocking system is stable based on LaSalles invariance principle. To evaluate the performance of the flocking system, we simulate the flocking system tracking a desired trajectory. The flocking algorithm is tested with three Pioneer robots and SICK laser scanners. Both of simulation and real robot experiments successfully show the proposed local sensor based algorithm works in the leader-follower flocking system.