February 8, 2005
News View Article
Swanson Center Leads RFID Tag DevelopmentPublished in the Jan/Feb 2005 issue of TEQ Magazine, a publication of the Pittsburgh Technology Council. --By Tim Palucka
Imagine pushing a shopping cart full of groceries through a checkout line without unloading the cart, having all your purchases recorded and billed to your credit card, collecting a receipt, and proceeding to your car without slowing down for a second, let alone standing in line for a half hour. Such a scenario could be a reality soon thanks to radio frequency identification (RFID) tags being developed by several Pittsburgh companies in collaboration with the Swanson Center for Product Innovation at the University of Pittsburgh. Dr. Marlin Mickle, Professor of Electrical Engineering at Pitt and Executive Director of the Swanson Center, says that RFID tags will largely replace bar codes whose item-by- item scanning requirement slows the checkout process to a crawl during busy shopping times. Instead of light rays scanning the pattern of a barcode, radio antennas will send out signals to a tag attached to each item, and will receive a return transmission containing the identification number of each item in the cart. In effect, all the products in your cart will be simultaneously "shouting out" their identity via radio waves to the antennas. A computer translates these codes into products and the prices, charges the items to the credit card you have on record, and sends you on your way. No checkout lines. The potential market for RFID tags is enormous. "Our best guess is that 500 billion tags per year will be required," Mickle says, noting that "there is not enough silicon capacity in the world today to produce that many tags." The current cost of approximately 20 cents per tag makes them practical only on high priced products; the industry estimates that costs will have to be reduced to less than 5 cents per tag to make their widespread use more feasible. There are basically two types of RFID devices: "passive" tags that absorb radio energy from the airwaves for power and "active" tags that require a battery. Both types contain a silicon microchip and an antenna. One passive tag made by Matrics looks like a pair of crossed T-squares printed on a piece 4-inch by 4-inch piece of adhesive paper. The arms of the T-squares are radio antennas, absorbing energy from the radio waves that pervade the air around us. The collected energy powers a tiny silicon microchip located at the intersection of the T-squares, which is programmed with the product code. Such a tag could be applied to the inside of a cereal box for retail product tracking. But retail is just one of the potential applications of RFID technology. Others include cybersecurity, medical implants, and defense applications. A tiny microchip affixed to a fingernail could be your password to gain access to a building or a computer system; a radio frequency implant could provide neuromuscular stimulation to stop tremors in patients with Parkinson's disease; an RFID tag stuck to a side of a building by a soldier could identify that site as a bombing target for an air raid. Since he started working with RFID tags about six years ago, Mickle estimates that more than a hundred companies interested in the technology have come to the Swanson Center, including local ones such as Mobile Aspects, Identifi Technologies, Inc., ClearCount Medical Solutions, and FnBiometrics. Mobile Aspects' iRIS T system includes a secure medical cabinet capable of taking an inventory of all items inside; tracking what was removed or returned to the cabinet reduces lost or misplaced hospital inventory, and helps to ensure that items are reordered in a timely manner when supplies run low. ClearCount Medical Solutions uses RFID tags on surgical sponges to keep track of them during surgery, and to make sure none are left in the patient afterwards. FnBiometrics develops RFID tags that attach to a fingernail for security identification purposes. Normally, you would suppose that medical applications would be much more demanding than retail ones, but that is not necessarily the case with RFID. For instance, the medical application addressed above by Mobile Aspects takes place in well-defined, controlled conditions-a secure medical cabinet. Compared to this, retail tracking is messy. Shoppers typically toss items into a grocery cart in a haphazard way, and making a detection system that can read the RFID code no matter the orientation of the package is not easy. A geometrical arrangement of three detectors-one overhead and one on either side of a radio portal that the shopping cart passes through-catches the great majority of items, but a few arranged with their tags edge-on to an antenna could go undetected, and thus be free of charge. Adding more detectors at various angles could help; unfortunately, the cost of the system becomes prohibitive. Increasing the strength of the signal is another possible solution, but FCC limitations and safety considerations place limits on this. Also, liquids, metals, and even the glue used on cardboard boxes can absorb radio signals. So companies like Identifi Technologies, Inc., that have targeted the retail sector face significant challenges. Currently Wal-Mart is leading the charge for effective item-level RFID tagging. The company had announced plans to have a checkout system in place by January of 2005, but the technical problems mentioned above have pushed the target back to 2007. Instead, they will implement RFID inventory of pallets of products in 2005, while engineers work out the details of item-level detection. Another big challenge is developing a standard for RFID technologies. While a frequency of 915 MHz is the United States standard, in Europe that frequency is reserved for truck drivers' communications. Also, the large number of companies developing separate RFID components has led to increased costs and confusion about the best product for a given application. The Defense Advanced Research Projects Administration (DARPA) has a contract with Pitt to develop a set of standard tests to compare the performance of these devices. To reduce costs and make RFID economical, "We need a standard for RFID tags so independent companies can mass-produce components," Mickle says. But RFID technology is just a small part of the capabilities of the Swanson Center for Product Innovation. Established by a donation from John A. Swanson of Ansys and located in the basement of Benedum Engineering Hall, the Institute acts as a portal to connect local industry to university resources. The facilities include innovative classrooms with computer clusters where students can work in groups to solve engineering problems using the latest software. Companies can come with a specific problem and hire the services of talented undergraduate or graduate students for a few months or a few years. They can gain access to instrumentation such as atomic force microscopes that are too expensive for most companies to buy, and to clean rooms that may be impractical to set up at their own facilities. In the W.M. Keck Rapid Prototyping Laboratory, engineers can "print" a three- dimensional wax or plastic replica of a prototype product directly from a CAD drawing. This puts a sample of the product in the hands of the developers quickly so they can examine features with their eyes and hands, instead of just looking at a drawing. Alternatively, they can take an existing product and "reverse engineer" it using lasers or a contact probe to scan the object and render a digitized blueprint on a computer. Successful designs can be manufactured in small batches in the Kresge Manufacturing Laboratory, completing the loop from problem to solution to finished product. Fiber optics gratings, microelectromechanical systems (MEMS), nanotubes, photonic circuits, models of human bones, lead crystal vases, harmonicas, and even specialized hotdog cutters have passed through some stage of development in this versatile engineering environment. But if you are looking for Marlin Mickle, better check out the Radio Frequency Shielded Laboratory, whose walls, ceiling, and floor are specially coated to prevent passage of stray radio waves. He and other Pitt engineers are trying to put the RFID antenna right on the silicon microchip to reduce dimensions and costs. Nano-RFID, anyone?
