Nonintrusive system for road traffic detection and characterization

Knowing the number, type, and velocity of the vehicles that drive along a road is extremely important to manage efficiently the traffic flow and also to estimate the environmental impact that the road may have in the surroundings. In this work the development and preliminary tests for a nonintrusive instrument and method for traffic characterization have been carried out. The system is part of a methodology to estimate the contaminants emitted to air due to urban and suburban road traffic. Based on a set of ultrasonic sensors, the system has shown reliability and accuracy in the determination of the number, type, and velocity of vehicles in a suburban road with several lanes and two ways. The success of this system lies on the method and data processing which overcomes the intrinsic noise problems of ultrasonic sensors. The developed system is easy to install and does not interfere with the road traffic. It is also of low cost, has no moving parts, and requires small power supply. The proposed system is an ideal tool to perform traffic studies where portability and low costs are required, for example, in environmental impact assessments studies.