Gathering on Rings for Myopic Asynchronous Robots With Lights
We investigate gathering algorithms for asynchronous autonomous mobile robots moving in uniform ring-shaped networks. Different from most work using the Look-Compute-Move (LCM) model, we assume that robots have limited visibility and lights. That is, robots can observe nodes only within a certain fixed distance, and emit a color from a set of constant number of colors. We consider gathering algorithms depending on two parameters related to the initial configuration: M_{init}, which denotes the number of nodes between two border nodes, and O_{init}, which denotes the number of nodes hosting robots between two border nodes. In both cases, a border node is a node hosting one or more robots that cannot see other robots on at least one side. Our main contribution is to prove that, if M_{init} or O_{init} is odd, gathering is always feasible with three or four colors. The proposed algorithms do not require additional assumptions, such as knowledge of the number of robots, multiplicity detection capabilities, or the assumption of towerless initial configurations. These results demonstrate the power of lights to achieve gathering of robots with limited visibility.
LCM robot system
ASYNC schedulers
myopic
luminous
ring networks
Theory of computation~Distributed algorithms
27:1-27:17
Regular Paper
Supported in part by JST SICORP Grant Number JPMJSC1806, Japan.
A full version of the paper is available at [S. Kamei et al., 2019], http://arxiv.org/abs/1911.04757.
Sayaka
Kamei
Sayaka Kamei
Graduate School of Engineering, Hiroshima University, Japan
Supported in part by JSPS KAKENHI No. 19K11828.
Anissa
Lamani
Anissa Lamani
Ecole internationale des sciences du traitement de l'information, Cergy, France
Fukuhito
Ooshita
Fukuhito Ooshita
Graduate School of Science and Technology, Nara Institute of Science and Technology, Japan
Supported in part by JSPS KAKENHI No. 18K11167.
Sébastien
Tixeuil
Sébastien Tixeuil
Sorbonne University, Paris, France
Supported in part by Hiroshima University and by project ESTATE (Ref. ANR-16-CE25-0009-03).
Koichi
Wada
Koichi Wada
Faculty of Science and Engineering, Hosei University, Japan
Supported in part by JSPS KAKENHI No. 17K00019.
10.4230/LIPIcs.OPODIS.2019.27
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Sayaka Kamei, Anissa Lamani, Fukuhito Ooshita, Sébastien Tixeuil, and Koichi Wada
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