Traffic control monitoring unit - photocells generate pulse rates for determination of speed, number and length of vehicles

摘要

The monitoring unit may either be located over a road on a fixed gantry or else on the underside fuselage of a traffic control aircraft. A lens located at the apex of a pyramid section housing has a ground glass screen on the top surface. The detector consists of a disc with two rows of photocells parallel to each other. The disc has an annular ring gear that may be rotated by turning an adjusting knob. The disc is mounted in a central plate that may be moved in one direction in a compound slide that is located in guides. For traffic monitoring the photocells are aligned perpendicular to the traffic flow. Pulse rates permit traffic parameters to be measured.