Energy Efficient Scheduling Algorithms for Sweep Coverage in Mobile Sensor Networks

Nowadays, with the development of micro-electro-mechanical technologies, sweep coverage with mobile sensors is more and more popular in wireless sensor networks, which is also applied widely in other scenarios, such as message ferrying and data routing in ad-hoc networks. In order to reduce the sweep cycle and the number of mobile sensors, we propose the Distance-Sensitive-Route-Scheduling (DSRS) problem, which is to consider the effect of sensing range. We prove that DSRS is NP-hard, and consider three different scenarios: the single sensing-point case, the general case, and the extended case. In the single sensing-point case, we propose an approximation algorithm ROSE to schedule the routes of the mobile sensors efficiently. For the general case and the extended case, we present two other approximation algorithms G-ROSE and E-ROSE based on ROSE. We further characterize the non-locality property and design a distributed algorithm D-ROSE, coordinating sensors to meet the sweep requirements with best effort. Our algorithms are scalable to different sweep coverage problems, and according to the simulation results, they greatly outperform other existing algorithms up to 45 percent especially with a large sensing range.