Tire sensors detect vehicle weight

January 30, 2013 // By Christoph Hammerschmidt
Automotive supplier Continental has announced to expand the scope of functions of its tire pressure sensors: Future sensor generations will be able to detect the total weight of the vehicle. With this move, the company intends to make a contribution to safety.

In today's passenger vehicles, drivers never really know if the weight of their payload lies within the safety limits or not. To close this gap, Continental is currently developing a generation of pressure sensors that are smart enough to determine the total weight of the vehicle.

For the automatic load detection system, the engineers take advantage of the physical properties of vehicle tires. The contact patch of the tire increases as a result of the weight bearing down on the tire. With the future generation of sensors, which will be fitted directly underneath the tread of the tire, the tire pressure monitoring system can accurately detect the size of this contact area. With the revolutions of the wheel, the associated pressure sensor registers the rolling characteristics of the tire on the road. Based on the existing tire pressure and precise data about characteristics of the tires fitted, the system is able to inform the driver after just a few hundred meters if a change in tire pressure would be appropriate for the current payload.

This kind of load detection also can be used as the basis for new assistance systems. Systems such as Electronic Stability Control (ESC), Emergency Steer Assist or Autonomous Emergency Braking Assistant can take the actual vehicle weight into account and thus achieve better results. In addition, it enables the design of a "Filling Assistant" which helps the driver to maintain the correct tire pressure even if he operates with non-calibrated filling equipment. According to Continental, an (unnamed) Asian carmaker is already making use of this smarter tire sensors in its Filling Assistant application. During the tire filling process the vehicle issues an acoustic signal as soon as the correct pressure level is reached.