Reactive Behavior in Self-reconfiguring Sensor Networks

We wish to create more versatile information systems by using adaptive distributed sensor networks: hundreds of small sensors, equipped with limited memory and multiple sensing capabilities will autonomously organize and reorganize themselves as ad-hoc networks in response to task requirements and to triggers from the environment. Distributed adaptive sensor networks are reactive computing systems, well-suited for tasks in extreme environments, especially when the environmental model and the task specifications are uncertain and the system has to adapt to it. A collection of active sensor networks can follow the movement of a source to be tracked, for example a moving vehicle, it can guide the movement of an object on the ground, for example a surveillance robot, or it can focus attention over a specific area, for example a fire to localize its source and track its spread. We build on important previous work by [1], [5], [2] and examine in more detail reactive sensors that can adapt to task and to the environment. We develop: (1) a protocol for adaptively selecting the active region in a sensor network for the tracking application and (2) a protocol for distributing the information in the sensor network for guiding the navigation of a user through the network area. We present algorithms for each of these problems, discuss an implementation using the Berkeley Mote sensors [3] and present some preliminary hardware experiments.