The KiTraffic Digital Weigh In Motion (WIM) system from Kistler has been awarded OIML certification by the Swiss METAS institute for metrology, confirming it as one of the most accurate weigh in motion solutions available on the market.
Overweight trucks and vans are a heavy burden for the traffic system. They create both significant costs for the public through damaged road surfaces and they are a serious safety threat for other road users. A seamless prosecution, however, requires the assistance of first-class technology. For a long time, the systems available have lacked accuracy, which has hampered their capacity for wider use. With the KiTraffic Digital Weigh In Motion system, Kistler provides a solution that makes prosecution effective. It facilitates both the weighing of vehicles in motion without impairing traffic flow and the direct enforcement of overloaded trucks.
Ready to enforce
Based on existing Weigh In Motion technology from Kistler, the system consists of multiple rows of sensor strips based on unique digitalized Lineas WIM sensors that calculate the wheel, axle and total weight of each vehicle. The sensors are equipped with piezoelectric quartz crystals that are built in the road surface. KiTraffic Digital works as a digital platform with open interfaces that allow for the integration of any existing additional components.
The KiTraffic Digital WIM system is designed to reach unprecedent accuracies and to eliminate potential sources of error. The WIM system delivers reliable results even when vehicles cross the individual sensors in a diagonal direction, for example when overtaking other trucks. Thanks to the new sensor design, the WIM system provides information on different tire types and draws conclusions about their condition. The system automatically records this information, thus providing a reliable data basis for law enforcement and increasing traffic safety.
Proven weigh in motion technology
The Swiss Federal Institute of Metrology, METAS, has now proven the system’s accuracy class for vehicle weight F5 with the OIML R134 certificate. Each class has a maximum permissible error (MPE) when it comes to initial verification for gross vehicle weight (GVW) and axle load. The accuracy class F5 indicates a MPE of +/- 2.5 percent of the GVW during initial verification. The KiTraffic Digital WIM system is the only technology available at this standard. The system was certified for a wide range of axle loads, ranging from 1 to 20 tons. The GVW is unlimited, with certified speed ranges between 10 and 100 km/h for heavy trucks, and up to 130 km/h for light vehicles and vans.
To reach the highest accuracy class, F5, three or four successive sensor rows need to be integrated into the road surface. For the accuracy class F10 it only takes two rows. It is possible to first install two sensor rows for statistical or preselection purposes, and upgrade to direct enforcement with one or two additional sensor rows later.
Though the OIML certificate is not binding for national legislations, it is still widely recognized. The METAS institute operates within the framework of the “mutual recognition of national measurement standards and of calibration and measurement certificates issued by national metrology institutes” (CIPM MRA). The agreement enables the mutual recognition of national standards and corresponding calibration certificates.
