Sensor Deployment and Coverage Maintenance by a Team of Robots

Abstract

Wireless sensor and robot networks (WSRNs) are an integration of wireless sensor network (WSNs) and multi-robot systems. They comprise of networked sensor and mobile robots that communicate via wireless links to perform distributed sensing and actuation tasks in a region of interest (ROI). In addition to gathering and reporting data from the environment, sensors may also report failures of neighboring sensors or lack of coverage in certain neighborhood to nearby mobile robot. Once an event has been detected, robots coordinate with each other to make a decision on the most appropriate way to perform the action. Coverage can be established and improved in different ways in wireless sensor and robot networks. Initial random sensor placement, if applied, may be improved via robot-assisted sensor relocation or additional placement. One or more robots may carry sensors and move within the ROI; while traveling, they drop sensors at proper positions to construct desired coverage. Robots may relocate and place spare sensors according to certain energy optimality criteria. This thesis proposes a solution, which we call Election-Based Deployment (EBD), for simultaneous sensor deployment and coverage maintenance in multi-robot scenario in failure-prone environment. To our knowledge, it is the first carrier-based localized algorithm that is able to achieve 100% coverage of the ROI with multiple robots in failure-prone environment since it combines both sensor deployment and coverage maintenance process. We can observe from the simulation results that EBD outperforms the existing algorithms and balances the workload of robots while reducing the communication overhead to a great extent.