While low-frequency radio frequency identification (RFID) has been used in the industrial world for more than a decade, particularly in the automotive industry, the recent decision by Wal-Mart and the U.S. Dept of Defense to move to ultra-high frequency RFID as a logistics and inventory management tool is driving widespread interest in the technology among both suppliers and potential customers.
RFID technology, with its superior reading and storage capabilities, has the potential to reshape business strategy by enabling companies to manage and track assets more efficiently through the supply chain, from the production process within a plant to the logistics process between locations. Unlike the ubiquitous bar codes they are intended to supplant, RFID transponders, known as tags, can be modified and are easily read in all kinds of environmental conditions. RFID tags are basically an electrical circuit that can be read or written by radio waves.
Until now, the high cost of RFID technology compared to bar codes had confined its use primarily to security applications and high-unit-value product manufacturing such as the automotive industry, where it was used to track vehicles moving through the assembly process and to provide intelligent interaction between different production stages. The decision by the world''s largest retailer to adopt RFID is expected to do for the technology what use in consumer and commercial applications did for Ethernet -- bring down the cost and drive supplier investment in technology improvements.
Industry experts believe that low-cost RFID technology will be a tremendous catalyst in the development of a true "Supranet," an "intelligent" environment where computer software and physical objects interact regularly, where manufacturing components "know" how to combine in assemblies and where offices "adjust" to whoever steps inside.
Unadopted Standards Hamper Supplier Investments
The biggest challenge to supplier investment in new RFID products is the uncertainty over standards. Wal-Mart''s decision to adopt ultra-high frequency (UHF) appears to run counter to the effort to create a global technology standard. While the 900 megahertz (MHz) frequency the company has selected for its RFID systems will enable it to achieve the long sensing distances required for its warehouse operations, this frequency band is reserved for cellular networks in Europe. The viability of UHF-based RFID products is consequently expected to be limited outside the United States.
In an effort to develop RFID standards for a wide range of applications, the ISO/IEC standards group has formed committees and has divided the RFID spectrum into five parts. The most significant international trend is the move from low frequency -- 125 kilohertz to 135 KHz -- to 13.56 MHz (Part 3). The UHF frequency band (Part 6) chosen by Wal-Mart and other U.S. companies actually runs from 860 MHz to 930 MHz.
The decision by Wal-Mart and the Dept of Defense to use the 900 MHz frequency is creating a serious challenge in terms of product investment decisions for all U.S. suppliers, including Schneider Electric. While no final decisions have been made by the ISO/IEC committees, Parts 1, 2 and 3 that includes the 13.56 MHz frequency is closest to being adopted as a global standard.
Given the short implementation schedules required by Wal-Mart, it''s expected that between two and three billion RFID tags will be consumed in the U.S. over the next three years. Millions of dollars will also have to be spent for stations, readers, and all the other hardware that will be required. It is an enormous market in terms of dollar value.
Since a number of major retailers have already announced that they will comply with whatever international standards are eventually adopted, companies and vendors can expect to be making significant additional investments in RFID technologies for many years to come.
Wal-Mart is moving quickly to implement its UHF decision. Suppliers are being required to declare whether or not their products will comply with the 900 MHz frequency. Their products must have read-write capability at a 10 ft sensing distance for both handheld readers and fixed antenna/stations to meet retailer requirements.
The primary challenge in developing products to meet these requirements is that metal objects easily reflect the 900-megahertz frequency. For this reason, providing read and write capabilities on both pallet level and case level will require installation of multiple antennas. A loading dock door, for example, will require a minimum of three antennas -- one for each side and one for the top. That''s because with one antenna, there''s only a 70-80% accuracy rate at 900 MHz. Even with three antennas, the accuracy rate is estimated at only 95%. Contrast this to bar codes, which have an accuracy rate of close to 100% but must have line of sight to be read.
Given that many of the proposed standards are still in committee and have not been adopted, as well as the obvious drawbacks to the 900 MHz standard as the technology currently exists, suppliers are faced with a very risky and potentially very expensive gamble if they pick a technology that doesn''t meet the eventual standard. This uncertainty may in fact cause delays in new product investments.
Why Should a Plant Engineer Care About RFID?
Some of the major retailers are suggesting that vendors adopt ultra-high frequency RFID in their own plants to provide traceability in the event of consumer product liability problems. This will require a major financial investment for product manufacturers that will affect plant engineers, and potentially their budgets. It has also raised concerns about privacy, such as how much information companies are going to be willing to share with customers.
On a broader level, RFID has major implications for both consumers and companies, since conceivably someone could use the technology for research and marketing purposes by scanning homes or businesses to find out who was using what products. For the time being, most retailers intend only to use RFID technology at the warehouse level for stocking and quality control purposes. Once the technology has been widely adopted, however, there is potential for RFID to become a major social issue.
A third challenge, and one that may be most problematic for companies, is how to handle the enormous amount of information that is going to be collected. Managing that data -- the software to handle it and how to store it -- will be a much bigger challenge for companies than what RFID hardware to use. It will be essential for companies to decide exactly what information they need, as well as what information they want to share externally.
Potential Applications For RFID Technology Are Limitless
A supplier like Schneider Electric, which has been making and selling RFID products for more than a decade -- everything from stations, antenna and amplifiers to tags -- is a source of expertise for plant engineers interested in applying RFID technology and who need to make RFID systems work with different industrial communications systems such as Ethernet, Modbus, FIP, Unitelway and many others.
There is tremendous potential for RFID technology, for example, in the pharmaceutical industry, which is desperate for a way to track information down to the pill level for many purposes, from quality control to FDA compliance to reducing manufacturing costs. Since RFID tags can be as small as a dime and a millimeter thick, it''s easy to attach them to a pill bottle.
Even without moving to UHF technology, existing RFID products that use lower frequencies can be used today in every industrial plant to improve routine or preventive equipment maintenance. On motors and other equipment that requires regular maintenance, for example, a machine''s entire maintenance history can be stored on an RFID tag to create a permanent service record. Plant engineers would never again have to worry about losing paper records or even electronic records if a computer crashes. The record would stay with the component forever and could be updated whenever service occurs.
The programmable logic controller which controls manufacturing processes and equipment is also a natural vehicle for feeding information into business systems. PLCs allow manufacturers to look at information from a system level, which will naturally make them the first level of filter for all the information that will be produced by billions of RFID tags.
Companies have just begun to think about ways to use RFID technology to improve business processes and product quality and to reduce manufacturing and operating costs. Although most RFID tags are now made out of some kind of plastic or engineered polymer, they''re essentially an electrical circuit that can be imprinted on almost any material.
Where necessary, RFID tags can be made virtually indestructible. For more temporary recordkeeping, on the other hand, conductive inks will allow you to print out an RFID circuit on paper or some other inexpensive substance. This will greatly lower the cost of technology adoption. And with nanotechnology coming in, manufacturers will even be able to weave RFID tags into textiles. The future applications for RFID technology appear limitless.