Device for finding out the proportion of non-typical mobile units

摘要

The invention consists of associating at least two systems (11) (12) transmitting and receiving sound or ultrasound electromagnetic waves placed at different heights and incrementing counters when the moving units (1) (2) pass by. The device according to the invention is particularly intended for the road traffic field, especially in order to evaluate the percentage of goods vehicles with respect to a total number of vehicles. <IMAGE>