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Vol: 54(68) No: 4 / December 2009 

A Search and Collect Algorithm for a Robot Swarm Under the Constraint of Multi-hop Communication Connectivity
T. Kovács
Department of Informatics, Kecskemét College, Izsaki 10, 6000 Kecskemét, Hungary, e-mail: kovacs.tamas@gamf.kefo.hu
A. Pásztor
Department of Informatics, Kecskemét College, Izsaki 10, 6000 Kecskemét, Hungary, e-mail: pasztor.attila@gamf.kefo,hu
Z. Istenes
Eötvös Loránd University, Faculty of Informatics, Budapest, Hungary, e-mail: istenes@inf.elte.hu


Keywords: robot swarm, ad-hoc network, connectivity

Abstract
The present paper investigates the reliability of the wireless multi-hop communication in an ad-hoc network formed by autonomous robots of a swarm, while the swarm accomplishes a typical searching and collecting task. This work also proposes a relatively simple algorithm for such a task that ensures a good communication connectivity of the swarm. Besides, the applicability and the limits of the proposed scheme are shown by the presented computer simulation. It was found that the expected value of the longest time while the communication network is disconnected increases exponentially with the radius of the searched area but does not depend considerably on the spatial density of the searched items.

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