Traffic density detection arrangement - has mirror between transmitter and receiver altering incidence of EM wave on CCD

摘要

The arrangement is designed to be placed on a section of one of the roads to be monitored and is equipped with an evaluating unit (A), provided for determining the traffic density, and with a plate (2), embedded in the road surface and level with it and turning in a vertical plane when a vehicle passes over it. There is a space (5) under the plate, accommodating a transmitter (S) and a receiver (9), with an optical component, a mirror (4) between them and mounted underneath the plate. The mirror moves with the plate, altering the incidence point of an electromagnetic wave on the receiver, a charge-coupled device. The plate is fitted with return springs (3,3') at each end, and any change in the output of the device is evaluated. USE/ADVANTAGE - Improved quantity of information obtd., numbers of vehicles, their speed and type. For local highway authorities.