A GPS-less on-demand mobile sink-assisted data collection in wireless sensor networks

The autonomous data collector is a role recentlyintroduced to improve the performance of Wireless SensorNetworks. When a prompt response for data processing andoffloading is necessary, i.e. in the case of event-driven networks,a mobile flying sink could be a good option for that role.In this paper, we introduce FreeFall, a distributed algorithmfor the autonomous navigation of a mobile collector through aWSN for on-demand data offloading that does not rely on anabsolute coordinate system. We show that, under fairly commoncircumstances, it is possible to set the trajectory of the mobilesink and fulfill the offloading requests without the needs ofadditional equipment installed on nodes. We show how our systemis preferable over more classical routing solutions especially in thepresence of localized generation of large amounts of information.