On federal highways, in front of each stationary photo-fixation complex, information plates are installed under speed limit signs. They notify drivers that they will be filmed. Can cameras see beyond this sign?
Current legislation requires road services to inform drivers about ongoing speed control. For this, information plates 8.23 ”Photo and video recording” and speed limit signs are used on federal highways. Almost all drivers, seeing such information structures, begin to brake, expecting to slow down to the permitted values. Does the camera have time to measure the speed to the sign?
How do cameras work?
On federal highways, you can see situations where the flow slows down when approaching photofixing cameras. The reckless people change their pace, calm down and move at the same speed as wagons and other slow-moving vehicles. But when passing the camera, they again return to the usual rhythm of movement and significantly exceed the speed.
As a rule, information plates with signs are placed at a distance of 150-200 m from the complex for fixing violations. A large boom with “boxes” located on it is discernible from afar, and when you drive closer, you can see the infrared illumination of camera lenses from about 50 m away.
As for the speed control devices, they have different ranges.
Most of the speed meters on Russian roads operate on the Doppler principle. They have a radar-type transmitter and receiver. First, the complex fires a probing pulse into the stream of cars, and then receives a reflected signal, which determines the speed. The impulse can go a thousand meters or more, but there is a problem with identifying cars in the stream. It is difficult to prove exactly which side the signal was reflected from. Therefore, together with the emitters, a camera is used, which is fixed on the target and accompanies it. An optical device can do this at a distance of 100-300 m, depending on the type of lens. It is difficult for the cameras to look further because of the slight elevation angle above the road.
What is the range?
Small stationary instruments “Chris” and “Arena” record the speed of vehicles at a distance of no more than 100 meters.
Portable “Cordon” and “Krechet” “shoot” at 150 meters. Within the line of sight, the device can establish the exact coordinates of a moving vehicle while simultaneously determining the speed in four lanes at once.
On multi-lane highways in Moscow and the Moscow Region, more advanced Strelka systems are used, which track the speed of dozens of cars and identify offenders with great accuracy. However, they can accurately determine the type of body and identify the object by dimensions and trajectory only at a distance of 250-300 m. At this border, the device captures the “target” and leads it to the place of photographic recording. The camera shoots the car at a distance of 50 m. Due to the limited range of infrared illumination, which is necessary to illuminate the license plate at dusk and at night.
Traffic police crews are sometimes armed with special speed meters that work on the basis of laser emitters. Instead of radio waves, they emit successive laser pulses, which are also reflected off objects and returned to the optical receiver. They accurately determine the speed for 500 m, but fixing the object and linking it to the speed is much closer. For example, the LISD-2F device detects intruders at a distance of about 250 m.
In general, the complexes for photographing violations have range restrictions.
Therefore, the placement of warning information structures on the roads at a distance of 150-300 m helps drivers to have time to adjust the speed. And if we take into account that cameras are installed on the most emergency sections of roads, then warning signs act prophylactically. Seeing such a sign at least 100 m away, motorists abandon unreasonable maneuvers and behave more responsibly.
Now the introduction of new Avtodoria complexes has begun, measuring the so-called average speed of a car. It consists of two chambers spaced from each other at a distance of several hundred meters to many kilometers. Both devices record the travel time and, based on the results, calculate the average speed in the controlled area. It makes no sense to slow down in front of such cameras. It is necessary to drive through the entire control area according to the rules.
