Sensor Line, the world’s first company providing fibre-optic (FO) load sensors for road, railroad and airport traffic, has introduced a new concept for automatic vehicle detection classification (AVC) and traffic data collection, combining the advantages of axle sensors with those of an inductive loop.
The CLASSAX is able to work with sensors that can be installed flush with the roadway surface, thus being protected against various possibilities of being damaged and avoiding producing noise. The detection zone is very well defined and can be made very short, which enhances reliability with slow traffic and is an essential requirement for true multi-lane capability. Moreover, all detection means required are available with static response, so the system is truly able to cope with traffic speeds down to zero.
Along with the philosophy of detection, CLASSAX also comprises a new method for setting up classification schemes. Traditional AVC systems have a fixed behaviour which is difficult or even impossible to modify because they were designed from scratch for distinction of a pre-defined set of vehicle classes. In addition, definition of the particular classes’ characteristics requires a large collection of vehicle data first, and both these data as well as the registration of the actual vehicle’s according parameters must be very accurate. This adds considerable extra effort to the development so setting up custom AVC systems is very expensive.
With CLASSAX, vehicle class characteristics are determined by a teach-in process utilising real traffic; no initial inquiry of vehicle data is necessary. All parameters are measured the same way as in operation, thus any systematic errors are automatically taken into account and therefore cease to be errors in the original sense of the word. The customer can define any set of vehicle classes desired: if they are only indicated by different vehicle characteristics the system will identify them faithfully. The cost of this teach-in process is negligible compared to what setting up a traditional custom AVC system requires.