Lufft's IRS31 Intelligent Road Surface Sensor is a passive sensor embedded in the monitored road surface, flush with the surface, to provide measurements of actual road conditions.
The IRS31 is a primary component of aRoad Weather Information Stations (RWIS). Two IRS21 sensors are typically installed at each measurement site.
The IRS31 measures the following parameters:
The sensors use radar techniques to measure water film.