TIRTL counts, classifies, determines the lane and measures the speed of passing vehicles using a unique non-invasive light based technology and is recognised globally for its technical excellence and application to numerous ITS challenges.  TIRTL is used for applications requiring accuracy and diverse vehicle information including vehicle detection / classification, freeway management, over-height vehicle detection, toll system revenue assurance, speed camera compliance and testing, heavy vehicle compliance and many other projects.  Its non-invasive measurement technique reduces installation time and costs, maintenance costs and road repair costs.  Our TIRTL production laboratory is NATA ISO/IEC 17025:2010 certified for speed calibration.


  • Advanced traffic detection including vehicle counting, classification and speed measurement
  • Speed and red-light enforcement (connected to a camera)
  • Freeway Management and Incident detection with TIRTLs installed at regular intervals (500m or 0.5mile) on a major road
  • Toll system revenue assurance to monitor the performance of a toll system
  • Heavy vehicle enforcement
  • Over-height and over-length vehicle detection
  • Bus-way lane enforcement
  • Train monitoring including direction, speed and length
  • Traffic monitoring for real-time applications
  • WIM support providing vehicle count and classification data, communications and data logging

TIRTL benefits: Operations and Maintenance

  • Competitive capital installation cost with low lifetime cost (25 years)
  • Low power consumption with reduced cost of solar power and O&M costs
  • Eliminate damage to road (extend life of road)
  • Reduced maintenance cost (10 min per TIRTL for annual cleaning)
  • Swap-out or re-install a new TIRTL in 20 minutes
  • Reduced lane closures and traffic management (maintenance off the road)
  • Not damaged by resurfacing of road
  • Product life of 25+ Years (MTBF of 10+ years) (no sensor failures)
  • Real time alarm monitoring with 99.95% uptime (20 alarms)
  • Real time traffic data for freeway & incident management
  • Remote upgrades & flexible interface to connect with VMS, camera, WIM…
  • Provides data for a broad variety of ITS applications

TIRTL: Vehicle Speed Detection

TIRTL uses two electronic devices (receiver and transmitter units) mounted on either side of a road.  It uses two infra-red light beams passing above the road surface to detect and record vehicles and their respective attributes.  The two beams are separated by 153.0 mm and span a road at wheel height.
As a vehicle moves along the road its tyres block and unblock each of the beams.  The TIRTL receiver detects and records the times that the first and second parallel beams are blocked and unblocked by the tyres of a vehicle.  Using these times, combined with the distance between the beams, the TIRTL receiver calculates the speed of each vehicle.  TIRTL calculates the speed of a vehicle using the times that the beams are blocked and unblocked thereby recording up to 4 speeds for a 2 axle vehicle.

Speed and Timing