Bridgestone announces new tyre technology for determining road surface conditions based on the concept of "CAIS"

Sep, 14 2011

Bridgestone announces new tyre technology

Bridgestone Corporation announced today that it has developed new technology that can provide real time road surface condition information to the driver by way of the tyres.

The new technology is based on a concept called Contact Area Information Sensing (CAIS*1).

CAIS is a general term for future technology which collects and evaluates road surface condition information. Capable of sensing instantaneous vibration input data and digitalising it by in-vehicle analysis equipment, the new technology classifies the current state of the road surface into seven conditions*2 and transmits this information directly to the driver through an in-car display*3.

By providing immediate road surface information, the new technology will allow the driver to be better prepared for rapid changes in dangerous driving conditions, such as ice, snow and rain, and also provides the opportunity to alert other motorist travelling with them on the same road*4. This new technology is one more way Bridgestone is promoting safety and peace of mind for drivers.

The following is an overview of the technology:

Overview of Technology for determining road surface conditions

An accelerator sensor located inside the tread of a tire detects vibrations in the tyre’s tread and wirelessly sends that information to the vehicle’s analytical equipment. Moreover, CAIS is powered by Bridgestone’s proprietary power generation equipment.
The analytical equipment analyses the vibrations in real time, and determines which of seven road surface conditions (dry, semi-dry, wet, slush, fresh snow, compact snow, ice) exist.
The results of the determination of road surface conditions are displayed on a monitor inside the vehicle.

*1. Contact Area Information Sensing. “CAIS” is a registered trademark of Bridgestone Corporation.
*2. Dry, semi-dry, wet, slush, fresh snow, compacted snow, ice
*3. The high precision of this road surface determination technology in various environments has been verified through extended testing over two winters on public roads in Japan (Hokkaido) where dangerous conditions like snow and ice are likely to appear. Detailed results of the tests were announced at the 2010 Annual Congress (Spring) of the Society of Automotive Engineers of Japan and at the World Automotive Congress of the International Federation of Automotive Engineering Societies.
*4. A driver of a car equipped with CAIS can share information on potentially dangerous road surface changes with other motorists who may be travelling with them on the same road.