An Overlay-Based Approach for Replacing Failed Sensors by Mobile Robots

Wireless sensor networks (WSN) are desirable to offer continuous services even in the case of sensor failures. Deploying redundant sensors or mobile sensors to guarantee service continuity may not be cost-effective. In contrast, this paper resorts to mobile robots that replace failed sensors in an on-demand manner. A rendezvous overlay is proposed on the top of wireless sensor networks in order to efficiently collect and disseminate sensor failure reports. Also optimal overlay size for sensor networks is presented. Simulation results show that our overlay-based approach outperforms two existing algorithms (i.e. dynamic distributed algorithm and centralized algorithm) with regard to the message overhead.