- Michelin this week revealed that it has begun fleet testing
of an RFID transponder embedded in its tires to enable them to be tracked
electronically. After it completes testing, which will likely last 18 months,
Michelin will begin offering automakers the option of purchasing tires
with embedded transponders.
- The US Congress passed the TREAD (Transportation, Recall,
Enhancement, Accountability and Documentation) Act in the wake of the Firestone/Ford
Explorer debacle. The act mandates that car makers closely track tires
from the 2004 model year on, so they can be recalled if there's a problem.
This technology could be available for the 2005 model year.
- Michelin hopes manufacturers will pay a little more for
tires with RFID transponders, because it makes the tires easier to track.
The microchip stores the tire's unique ID, which can be associated with
the vehicle identification number. The chip can also store information
about when and where the tire was made, its maximum inflation pressure,
size and so on. Information can be updated with a handheld reader.
- Other tire makers have demonstrated the ability to read
RFID transponders embedded in tires. But Michelin claims to be the first
to meet the Automotive Industry Action Group's B-11 standard for North
America, which calls for a read distance of 24 inches. Achieving that range
has been a challenge because the rubber makes it harder to read the tag.
- When Michelin took off-the-shelf, passive UHF transponders
and embedded them in tires, the read distance dropped to less than three
inches, according to George O'Brien, Michelin's North American technical
director for electronic products and services. To boost the read range,
the company took microchips from Fairchild Semiconductor and Philips Semiconductor
and designed its own special antenna.
- O'Brien would not reveal details, but he said the antenna
was designed to compensate for the fact that electromagnetic waves travel
differently through rubber than through air. He said the transponder that
his team designed loses only 10 percent of its read range when it is embedded
in a tire.
- The other key issue was to ensure that the rubber bonds
to the antenna. Michelin developed a proprietary coating it puts on the
transponders before putting them into the rubber. "The most important
concern is making sure the tire is not compromised in any way," O'Brien
says. "You have to make sure the rubber bonds carefully to antenna
so the wire that the antenna is made from doesnít break and then
work its way out of the sidewall of the tire."
- The tire is now being tested in several areas of the
country by taxi and rental car fleets. Michelin says the transponders cost
"several dollars" today, but the price will drop if they are
manufactured in mass volumes (Michelin manufactures more than 800,000 tires
a day). It's not clear yet whether automakers will be willing to pay the
- The Fairchild and Philips chips are based on Intermec's
Intellitag. Saleem Miyan, Philips global strategic business manager for
RFID products, says his company made some refinements to the Intellitag
design, which it has licensed from Intermec.The Philips I-Code HSL chip
operates at 868-915 MHz stores about 2 kiliobytes of information. It is
currently available only in sample quantities. it will be mass-produced
starting in the middle of the year.
- Philips and Texas Instruments have also developed pressure
and temperature sensors that use battery-powered RFID tags to communicate
with a reader in the dashboard. That enables the driver to know when the
pressure of one particular tire drops below a certain level (see RFID Chip
To Monitor Tire Pressure). The Michelin transponder is strictly for identification