Stabilizing flocking via leader election in robot networks

Abstract

Flocking is the ability of a group of robots to follow a leader or head whenever it moves in a plane (two dimensional Cartesian space). In this paper we propose and prove correct an architecture for a selforganizing and stabilizing flocking system. Contrary to the existing work on this topic our flocking architecture does not rely on the existence of a specific leader a priori known to every robot in the network. In our approach robots are uniform, start in an arbitrary configuration and the head of the group is elected via algorithmic tools. Our contribution is threefold. First, we propose novel probabilistic solutions for leader election in asynchronous settings under bounded schedulers. Additionally, we prove the impossibility of deterministic leader election when robots have no common coordinates and start in an arbitrary configuration. Secondly, we propose a collision free deterministic algorithm for circle formation designed for asynchronous networks. Thirdly, we propose a deterministic flocking algorithm totally independent of the existence of an a priori known leader. The proposed algorithm also works in asynchronous networks. © Springer-Verlag Berlin Heidelberg 2007.