Speed enforcement system which triggers higher-accuracy active sensor when lower-accuracy passive sensor detects a speeding vehicle

摘要

Vehicle speed is measured by continuously monitoring traffic with an image capturing unit 102 and controller 240; estimating 254 the speed of a vehicle 205 in the effective field of view; triggering 252 a burst of radiation from an associated remote sensing device 104 when the estimated speed exceeds a threshold 250; and determining an accurate vehicle speed. The image capturing unit may be a video camera and the remote sensing device may be a LIDAR or RADAR gun. A transverse component 260 of the vehicle velocity may be computed by the camera and applied to the remotely sensed reading to correct a cosine error. Determining accurate speeds may be carried out in a sequence ordered according to the estimated speeds of multiple vehicles. Offending vehicles may be identified from captured images using licence plate recognition 280 and violation tickets 118 may be automatically issued.