What is "tirtl"

The Infra-Red Traffic Logger, more commonly known simply by the acronym TIRTL, is a multi-purpose traffic sensor that can be used as a traffic counter, speed sensor, red light camera sensor, heavy vehicle tracker, overheight vehicle sensor, rail crossing sensor and network management system. The initial development of the device started in 1997 in conjunction with the New South Wales Roads and Traffic Authority & started commercial domestic and international sales in 2002. It is currently in use in sixteen countries.

It uses infrared light cones sent from a transmitter to a receiver situated on opposite sides of the road perpendicular to the flow of traffic. It has the ability to classify, record speed, and record volume for motor vehicles. The unit's data logging capabilities are enhanced by several flexible options for output. These options allow for real time applications, such as variable message sign triggering and traffic enforcement, as well as data logging for statistical purposes.