Innovative WIM Sensor Layout

Commonly Used Layouts

Piezo polymer sensors, such as RoadTrax BL, are commonly added to the layout. They are installed approximately under a 20–40-degree angle to the weighing sensors and are used for measuring axle tracks, detecting the vehicle’s position in lane and for dual tire detection. These outputs are very important for classifying purposes and for measurement validation.

CAMEA's Innovation

CAMEA developed advanced WIM algorithms that allow installing the weighing sensors in place of the position sensors (quartz or strain gauge instead of piezopolymer). Thanks to that, less sensors in total need to be deployed which not only saves costs but facilitates cabling works as well. For instance, a configuration of 4 weighing (2 rows) + 2 piezo polymer sensors can be replaced with only 4 weighing sensors of the same or combined technology, as per the pictures below.

The innovation brings further improvements:

• More reliable dual-tire detection,
• More accurate and reliable position-in-lane detection,
• More accurate and reliable axle-track measurement.

The layout also offers new functionalities:

• Weighing with tilted (position) sensors,
• Tire pressure measurement.

To summarize the presented innovation, a CAMEA’s SW upgrade now enables installing the WIM with the sensor layout that provides system users with better results for lower price and less works.