Sensors for free-flow tolling
The free-flow tolling is a new system in which motorists do not need to stop at toll plazas to pay their toll tax. The aim is to replace the traditional systems where motorists have to stop (manual lanes) or slow down (automatic lanes), with portals equipped with technological devices. These devices are able to detect vehicles traveling at a normal speed and charge the corresponding price. The great advantage of this system is to avoid traffic congestion and keep traffic flowing, reducing the travel time loss.
Portals for free-flow tolling are quite complex and are equipped with the following devices:
- Cameras for plate recognition (ANPR)
- Sensors for vehicle detection and classification
- RFID antennas to communicate with on-board units (OBU)
The laser scanner sensors fit perfectly to the free-flow tolling system as they ensure highly accurate vehicle separation, counting and classification. These sensors are also used to trigger cameras, i.e. they activate the plate detection as soon as a vehicle passes under a gantry.