Information Surfing for Radiation Map Building

We develop a control scheme for a group of mobile sensors to map radiation over a given planar polygonal region. The advantage of this methodology is that it provides quick situational awareness regarding radiation levels, which is being updated and refined in real-time as more measurements become available. The control algorithm is based on the concept of information surfing, where navigation is done by following information gradients, taking into account sensing performance and the dynamics of the observed process. It is tailored to cases of weak radioactivity, where source signals may be buried in background. We steer mobile sensors to locations which are critical points of a function that quantifies the information content of the measured signal, while ∗Corresponding author the time-asymptotic properties of the selected information metric facilitate the stability of the group motion. Information surfing allows for reactive mobile sensor network behavior and adaptation to environmental changes, as well as human retasking. Computer simulations and experiments are conducted to verify the asymptotic behavior of the robot group, and its distributed sensing and mapping capabilities.