DOD uses RFID for logistics tracking

Radio frequency identification is already established in the realm of defense logistics, helping to keep tabs on the mountains of materiel moved through the military services’ supply chain. But RFID applications are also moving beyond those needed for supply chain visibility.

Radio frequency identification is already established in the realm of defense logistics, helping to keep tabs on the mountains of materiel moved through the military services’ supply chain. But RFID applications are also moving beyond those needed for supply chain visibility.

“It’s increasingly now also about property accountability within four walls,” said Maryam Esfarjani, a senior associate at consultant Booz Allen Hamilton and the lead for its RFID information technology business. “It’s being used to track secure servers on a rack, for example, so that people know — if they are not where they are supposed to be — that they’ve just been moved and not stolen.”

Some military installations are picking up on the concept. Walter Reed Army Medical Center is planning to use a real-time location system that employs active RFID tags to track some 4,000 pieces of equipment in the hospital. The Defense Medical Logistics Standard Support system is planning for greater use of RFID throughout the military health system in fiscal 2008.

The technology is also beginning to be used to more closely track items used for repairs at large depots. A pilot that began in 2005 at the Tobyhanna Army Depot in Pennsylvania, which repairs and overhauls surveillance and radar systems, proved the worth of active RFID technology by cutting the number of days needed for system repairs and eliminating the need to reorder parts that can’t be located.

The Navy is also using RFID as a part of its Advanced Traceability and Control program to track the movement of various materials and failed parts sent from overseas to its Naval Aviation Depots and civilian repair yards.

Those innovative uses for RFID, Esfarjani said, are being driven from the grass roots at these facilities, which are under pressure to do more with the resources they have. She said she knew of at least two fairly large Army organizations that are using or planning to use RFID this way, though she wouldn’t name them.

Following mandates issued several years ago by the Defense Department, RFID technology has become one of the major elements of the military’s Automatic Identification Technology logistics tracking program. The goal of AIT, which also includes technologies such as bar codes, satellite tracking systems, smart cards and optical memory cards, is to provide military commanders with the ability to continually track where assets are in the logistics pipeline, giving them close control over the deployment of personnel and materiel.

Active RFID tags broadcast their data in response to a signal from a reader. Because they are powered by a battery, their information can be read from as far away as 300 feet. And they can carry more data than passive tags. But they are more expensive and generally reserved for tracking larger assets such as vehicles, containers or pallets. Passive RFID tags, on the other hand, are basically printed circuits on a sticker. They have no battery, generating their signal from the power of the reader scanning them. Passive RFID tags carry only basic identifying data and can be read only from a few feet away, but they are relatively inexpensive.

Active RFID is now a relatively mature technology, said David Dias, chief of the Asset Visibility Division at the Transportation Command, which has been given the lead to expand the implementation of AIT and RFID throughout DOD. Passive RFID, on the other hand, is a work in progress.

“By its nature, passive RFID is not as mature as the other technology,” he said, “but we believe it’s the next revolutionary step for AIT.”

It has the potential, for example, to provide a live delivery record that would automatically feed information into a payment system, dramatically speeding payments for supplies and cutting out the need for people to physically enter that payment and contract information. However, it could take until 2015 to fully evaluate passive RFID, Dias said.

Meanwhile, the technology is changing.

Active RFID tags, for example, are getting smaller and cheaper and being integrated with different communication mediums, such as the Global Positioning System, General Packet Radio Service and satellites to give their capabilities a broader reach.

“When you combine RFID with satellite, vehicles in motion can transmit the real-time location and condition of their cargo,” said David Stephens, chief executive officer at Savi Technology, the primary supplier of active RFID technology to DOD. “You can keep track of all kinds of cargo that way to provide a common operating picture of logistics on the battlefield.”

Without satellite communications, cargo bearing active RFID tags would have to pass by land-based readers before they could be tracked. However, that gives only a historical sense of where any cargo has been, because the location is based on the last tag reading. RFID with satellites provides an as-is understanding of location. Satellites also promise a way to track supplies in remote areas that have no fixed infrastructure for reading tags, the kinds of environments warfighters usually find themselves in when they request supplies.

It could be some time before RFID technology is widely used in the military, but DOD has been testing it. The Defense Logistics Agency began proof-of-concept work several years ago on a system called Third Generation Radio Frequency Identification with Satellite Communications, combining RFID with GPS and Iridium satellite communications.

Meanwhile, the private sector is increasingly getting in on the act. Orbit One, for example, an established provider of satellite–based solutions for emergency and disaster work, recently introduced its Global-RFID technology platform, an active RFID tag that includes a field-replaceable lithium battery, an internal motion sensor and an integrated GPS chipset that communicates with low-Earth orbit satellites.

RFID does have a problem working properly in environments that are full of metal or are saturated with liquids. Many of the wireless frequencies used with both active and passive RFID bounce around between metal objects. Some frequencies are also absorbed by liquids.

There are work-arounds using different ways to mount the RFID tags on objects and using lower frequencies, but they also have trade-offs in terms of read ranges and the speed at which tags can be read.

That was the problem Oak Ridge National Laboratory (ORNL) faced in trying to design a solution to track the guns used by the Energy Department’s security force. DOE requires all issued firearms to be counted at the beginning of each shift and inventoried weekly. This took a significant amount of time and manpower to complete manually.

Last year, ORNL began testing the prototype of a Weapons Inventory Tracker System that uses RFID tags integrated into the grip of a weapon. The most innovative aspect, however, is that they use a different kind of wireless technology that is unaffected by metals, liquids and electromagnetic noise.

Known as RuBee, it uses magnetic waves rather than radio waves to send its signal to a reader and can be used in active or passive tags.

It’s a slow technology, and only a handful of RuBee tags can be read in a second, but for the kind of deliberate inventorying application being developed by ORNL, it’s ideal.

RuBee tags typically have a battery life of 10 to 15 years and can be read from as far away as 100 feet.

“We are also one of the [few] technologies on the planet that has dynamic range management, which means there are no attack or eavesdropping threats against it,” said John Stevens, chairman at Visible Assets, the developer of RuBee. “That means we won’t be banned from high-security areas, and in fact, we are in some of the most secure places already.”

Visible Assets is working with Sig Sauer, one of the world’s largest weapons manufacturers, on the ORNL system, and Stevens said his company has gotten interest from DOD following demonstrations of the technology at recent trade shows. The RuBee protocol is set to become an Institute of Electrical and Electronics Engineers standard soon, probably this year.

RFID is also turning up in places that few people probably thought it would, such as the barrel of a gun.

In September, the Army’s Benét Laboratories awarded Augusta Systems a $1.18 million task order to develop and implement an RFID-based system to track how many rounds are fired from tank guns or mortar equipment. Warfighters now have to do that, by hand to tell when the guns need to be serviced.

The automated system Augusta is developing uses a piezoelectric sensor that measures the force each time a round is fired from the barrel.

The RFID tag in the system stores the number of times the gun fires, and that information is automatically read from the tag each time the tank or mortar returns to the weapons depot.

The system is expected to be ready for production before the end of 2008. The company said it is already talking with a number of defense agencies and prime contractors to assess their needs for distribution of the system.

“This really is on the leading edge of such RFID developments,” said Patrick Esposito, president and chief operating officer at Augusta. “But I think what’s being produced here is a part of the tangible benefit of the weapons supply chain, and it’s of direct advantage to the warfighter.”

About the Author

Brian Robinson is a special contributor to Defense Systems.

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