Multi Robot Coordination in Area Exploration Based on a Fixed Linear Chain Bluetooth Communication

In the first part of the present paper, a multi-robot system can be highly beneficial for exploration, which is a core robotics task. We know that this exploration task is best performed when using a multi-robot system. We present an algorithm for multi-robot exploration of an unidentified environment, placing into account the communication constraints between the robots. A novel communication scheme of an autonomous robot team via Bluetooth radio is investigated. In the presented solution, an autonomous unit is equipped with two independent Bluetooth radios and so a relatively fast communication is possible in the team in a static (i.e. no ad-hoc) networking topology. An autonomous robot is a machine able to extract information from its environment and use knowledge about its world to move safely in a meaningful and purposive manner. The performance of such a network was tested by implementing a linear graph topology by NXT robots. It was established that the reliability and the speed of such a communication scheme are satisfactory and give rise to applications in a robot team manage task. In the second part of the paper an area exploration method is presented based on the static linear communication system above. The method was tested by computer simulations for various obstacle configurations and density. It was establish that the proposed method performs better than the chosen reference methods in the case of zero or low obstacle density and when high (75% or 100%) exploration ratio is necessary. With a simple verification, we have shown that the proposed (fixed chain-like team) exploration method is optimal in the obstacle-free case under the constraint of the connectivity with the base station.