Issue #67 | July 6, 2006 |
Tire manufacturers have been some of the earliest users of RFID technology, at least what we might call the new wave of RFID. Both Goodyear and Michelin, as two examples, have RFID projects that predate the paradigm changing Wal-Mart and Dept. of Defense announcements by years.
In fact one of the common examples I heard used most frequently a couple of years back as an example of RFID?s value beyond supply chain compliance was for tire recalls. The story went something like this: "Instead of having to recall tires nationally or 'from the East Coast,' tire companies will be able to recall a bad lot from the twelve stores they were distributed to." You didn't have to be a tire expert to imagine how much money could be saved in such an example.
Yet RFID is not just used for identification and tracking of tires in the supply chain. When the tag is embedded in the tire, a whole new set of benefits can be derived. Tire manufacturers are getting pressures from retailers, the DoD, aerospace and other industrial corporations. It should be no surprise in that the automotive industry, too, is rapidly adopting RFID technology. Some analysts' projections anticipate auto-related RFID investments approaching as much as $2 billion by 2011. We at Switchboard predict that long before that automobile manufacturers will have RFID mandates of their own, much like the aeronautics manufacturers do. If so, that $2 billion figure will have been surpassed in less than five years. Tires are what all this is riding on.
Benefits beyond the vehicle supply chains are so numerous you may find them, well, tiring. Manufacturers see potential improvements in their control processes, replenishment, asset utilization, quality control, fleet servicing and down time, and safety and related personnel and insurance savings. Dealerships and service centers can achieve better inventory control, traceability for re-calls and warranty service.
RFID can even make it safer for drivers. Before I jump into that, let me give you some background.
The Automotive Industry Action Group (AIAG) defined a standard for the printing and placement of tire and wheel identification bar code labels and read/write RFID Tags. The B-11 standard, originally published in 1994, is designed to 'help automate the collection of tire and wheel information and the mounting and assembly process of tires and wheels with vehicles in the OEM environment.' The B-11 standard specifies read/write, passive RFID tags and earlier this year, it evolved to incorporate ISO 18000-6c/EPC Gen 2. By using the Gen 2 standard and the additional memory those tags provide, RFID can identify the tires Electronic Product Code, Department of Transportation tire identification number, and the tire cure date (date of manufacture).
If you have ever tried to tag tires using RFID labels, you?ll find they don't work so well. During transportation and handling, the labels are easily damaged due to the tires? banging together and rolling around. If that isn?t bad enough, tires actually exude oils, making it more difficult for the label to remain adhered to the tire over time. Simply put, labels can fall off without the right adhesive. For bar codes and human readable information, cloth labels tend to work best; but I have only seen RFID cloth label tags used on clothing, never yet on tires.
Michelin has developed a patent-pending RFID tire transponder, pictured below, which consists of a UHF RFID integrated circuit and two spring-wire antennas. Not only does the tag identify the tire, it actually monitors the tire temperature and pressure, using the kinetic energy from the tire to power itself as it rotates.
Tests show that the best location for the tag is embedded into the sidewall of the tire. If you think transportation and handling is tough on a tire, consider how much punishment a tire gets during its life and what that would do to an RFID tag. The designers have gone to great lengths to protect the tag from its operating environment as well as the manufacturing process involved with curing the tag into rubber. The transponder can be read or programmed at temperatures between -40C and 85C and under maximum tire inflation pressures of up to 60 pounds per square inch (psi) for passenger cars and light trucks. It can survive and retain any programmed data at up to 175 deg C for 20 minutes and molding pressure > 50 bar.
My team is using these embedded Michelin tags in a project for a trucking company based in Mexico. They face a significant pilferage problem. They put new tires on trucks and, when the truck returns from a trip, one or more of the new tires have been replaced with old worn-out tires. Apparently, there is a significant Mexican black market for new tires.
It is extremely hard to inspect every tire of every truck when you have a fleet of over a thousand trucks and more than one hundred truck shipments per day each. Each truck has 18 wheels, resulting in over 50,000 tire inspections per month!
Previously, the company hot-branded a unique identifier to quickly identify their tires. However, the brands were quickly counterfeited, so they decided to try Michelin tires with embedded tags. An RFID-enabled portal was installed at the gate to the yard, with readers on both sides of the driveway. A metal-mount RFID tag is affixed to the trailer, which specifies how many tires should be read, and ensures tires are there and in their correct configuration.
The outbound system records all the information when the truck leaves. The inbound system has feedback: a red light illuminates if inspection is required; a green light is everything checks out; and a yellow light flashes while the system is processing. The system even automatically opens the gate to let the truck in. If the wrong tires are found on the vehicle, the company can take actions, such as charging the driver.
The customer also uses GPS to know the location of the trailers, but found GPS did nothing to address the tire problem. Another additional benefit the RFID based system provides is it very well suited for trucks used on short trips of one hour or less. The time is automatically captured when a driver leaves one location and arrives at another, which allows the average speed of the truck during the trip to be determined. The customer is looking at adding additional portals at some of the stops.
To me, the most amazing benefit of the tire tags is a system Michelin developed that actually uses an RFID reader in the car that monitors the tire's pressure from the tag. It also uses the manufacturing information stored on the tag to notify the driver via a display in the vehicle when service or replacement is required. This revolutionary solution will truly make it safer for drivers everywhere.
