Average speed camera systems are designed to enforce speed limits over a specific stretch of road, typically known as a "speed enforcement zone." While there are no visible start or ending lines for these cameras, they use advanced technology to accurately measure the average speed of vehicles traveling within the designated zone.
Here's how average speed cameras work:
Camera Placement: Average speed cameras are installed at specific points along the road, usually mounted on gantries or poles. The cameras are positioned to cover the entire enforcement zone.
ANPR Technology: Average speed cameras are equipped with Automatic Number Plate Recognition (ANPR) technology. This technology reads and records the license plate of each vehicle passing through the camera's field of view.
Timestamp Recording: As a vehicle passes the first camera, its license plate is recorded along with a timestamp. As the vehicle moves through the enforcement zone, it passes multiple cameras, each of which records additional timestamps.
Speed Calculation: By comparing the timestamps and the distance between the cameras, the average speed of the vehicle is calculated. The time it took the vehicle to travel from the first camera to the last camera is divided by the distance, giving the average speed over that stretch of road.
Violation Detection: If the calculated average speed exceeds the speed limit for the zone, a violation is registered, and appropriate enforcement action, such as issuing a speeding ticket, may be taken.
The lack of visible start and ending lines is intentional, as it helps avoid abrupt speed changes near the camera locations, promoting a smoother flow of traffic and encouraging drivers to maintain a consistent speed throughout the enforcement zone.
Some key advantages of average speed cameras include:
- Encouraging more consistent speeds throughout the enforcement zone, reducing the likelihood of sudden braking or acceleration.
- Discouraging "speeding and braking" behavior, which can lead to traffic congestion and potential accidents.
- Effective enforcement over long distances, as they monitor average speed rather than just a single point in time.
- Reducing the need for visible police presence and manual enforcement.
Overall, the technology behind average speed cameras has been refined over the years, making them a reliable and effective tool for enforcing speed limits over designated road sections without the need for traditional start and ending lines.