Automotive

Bridgestone’s new car tire technology detects road conditions

Bridgestone’s new car tire tec...
Bridgestone's CAIS technology uses the car's tires to inform the driver of road surface conditions in real time
Bridgestone's CAIS technology uses the car's tires to inform the driver of road surface conditions in real time
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Bridgestone's CAIS technology uses the car's tires to inform the driver of road surface conditions in real time
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Bridgestone's CAIS technology uses the car's tires to inform the driver of road surface conditions in real time
The Bridgestone CAIS system uses an acceleration sensor powered by a micro generator and transmits wirelessly information to the main module inside the car
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The Bridgestone CAIS system uses an acceleration sensor powered by a micro generator and transmits wirelessly information to the main module inside the car
The Bridgestone CAIS technology development roadmap
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The Bridgestone CAIS technology development roadmap
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The Contact Area Information Sensing (CAIS) system includes a sensor on the tire's internal wall that monitors its interaction with the road surface and informs the driver accordingly. In development since 2011, the CAIS is finally ready for commercial applications.

Bridgestone unveiled this technology at the 2011 Frankfurt Auto Show, with a first version that used a strain sensor to calculate the load and side forces acting on the tire. The CAIS 2 version followed with a new acceleration sensor that could identify the road surface conditions, and in 2014 the CAIS 3 was introduced, having evolved into a system that could also monitor the tire's wear.

The latest release from Bridgestone's Japanese headquarters announces the commercialization of the CAIS 2 setup.

Aimed at car and truck tires, this system relies on an acceleration sensor placed on the inside wall of the tire, powered by a proprietary electromagnetic generator. Its task is to monitor the high frequency vibrations of the tire and transmit them wirelessly to the CAIS central module that's housed inside the car.

There the data are compiled and translated to the actual road surface conditions, distinguished in seven different states: dry, semi-dry, wet, slush, fresh snow, compacted snow, ice. This information is then conveyed to the driver via a digital screen, providing a vital understanding of the road conditions in real time.

For Bridgestone this is just the first step, as future plans include sharing this information to vehicles following behind. This of course is not entirely up to the Japanese company, requiring a broader communication infrastructure that includes both the road and the vehicles on it. Such Intelligent Transportation Systems have been in development for several years in Japan, Europe and USA, and Bridgestone appears to have a head start over its competition.

With plans for commercial application of the CAIS 3 system in the near future, coupled with the widely used air pressure sensors, Bridgestone could soon have tires on offer that communicate to the driver comprehensive information on every aspect of the tire's interaction with the road: air pressure, tread wear and road conditions.

Source: Bridgestone (in Japanese)

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3 comments
Mel Tisdale
This technology needs to talk to the car's onboard control system. It should not be up to the driver to take any action with regard to the road surface; the responsibility should lie with the systems controling the car. The graveyards are already occupied by more than enough clowns who thought that they knew better than all the warning signs flashing at them.
As for warning following drivers, surely it would be better if the information were to be transmitted to - and stored in - road signs or other roadside 'furniture' and re transmitted accordingly. In that circumstance cars approaching dangerous conditions would be warned much earlier. (Some way of showing the age of the information would be advisable.)
Bob Flint
Although I agree with you Mel,the information overload on those clowns, it would be better input directly to the traction control system of the car itself.
As the icy conditions can change within the small patch of rubber from sunny wet to shady patches of ice in less space than the rotational diameter of the tire, is there enough time for data transmission when traveling at 88 feet per second (60mph)By my calculations you would need better than 14 milliseconds to just receive the single rotation of a 15" tire. That would be about 6.28 feet of rotational distance and the rubber patch is about.5 feet. So when the grip no grip occurs within less than 6 feet it's already too late your sliding.
TomSmithdeal
It's about time that car's had sensors to tell me that the road is wet when it is raining. All these years, I have been driving around when it rains wondering if the road is wet but not being absolutely sure. What a relief that I won't have to wonder much longer.