“ Wireless Visual Sensor Networks for Urban Traffic Management ” NIST Technology Innovation Program ( Complex Networks and Complex Systems ) White Paper

The Problem Urban areas face increasingly acute vehicular traffic congestion. Current methods for measuring traffic flow on a real-time basis are antiquated and limited in their capacity to assess traffic dynamics. Buried inductive loop detectors at intersections are extensively used in the USA and Europe to measure traffic speed, occupancy and volume on freeways and arterials. The data obtained is used by traffic management centers to make real-time operational decisions such as timing ramp meters, incident detection, congestion identification, actuated signal timing and control [1], [2]. However, street loop detectors suffer from serious limitations. Firstly, the installation and maintenance cost are very high, requiring saw cuts into the pavement, causing