Car Insulation Maker Uses Hybrid System to Track Materials, Products

In early 2007, MWAAF first began working with Analytica, which developed a hybrid system using bar codes to identify each item, and RFID to determine the locations of those items within the building, explains Analytica's president, Vikram Seshadri. By December 2007, the system was deployed at one assembly line, and in 2008, it was expanded to the remainder of the plant.

With the new system, when MWAAF employees receive rolls of raw materials, they utilize an Analytica handheld device to scan each roll's bar-code label, then transmit the bar-code number, as well as the device's own unique RFID number. The device's 2.4 GHz signal is received by the nearest Analytica RFID reader node. MWAAF installed an interrogator at the end of each of its 20 assembly lines, as well as four more in the warehouse areas. Each reader represents one zone within the building. An interrogator passes this data, including its own ID number, from reader node to reader node, until it reaches the company's back-end system.

Analytica's Crossfire Web-based software provides a display of the facility's floor map, with Google Maps-style markers indicating specific items, and the specific zone in which they can be found. Crossfire, integrated into MWAAF's ERP system, also provides business analytics—such as how long it takes for a roll of raw material to be consumed on a particular assembly line—and thereby calculates the operation's efficiency. Midwest Acoust-A-Fiber can then see when the roll was received, when it was moved into storage, and when it was brought to an assembly line, as well as to which assembly line it went.

When a product is assembled and packed into a box, a bar-coded label is applied to that carton and scanned as the item is moved into a finished-product storage area or is shipped to a customer, with the RFID and bar-code scanner again transmitting the zone in which it is located. One zone is dedicated to outgoing shipments, so that whenever a product is scanned in that location, the system automatically knows that that product is shipping.

The greatest challenge with the system, Callahan says, involved ensuring against cross-reads between the multiple readers. The reader nodes, suspended from the ceiling above warehouse space and assembly lines, have a read range of approximately 20 feet. "We combated the problems of cross-reads by turning down the [sensitivity of] the readers," he says. "We've got it working pretty decently now."

Any problems the system encounters, Callahan explains, tend to be the result of improper use by the staff, such as failing to scan the bar-coded labels. The RFID readers need to be rugged in order to sustain the high temperatures on the plant floor—as much as 140 degrees Fahrenheit (60 degrees Celsius). The handheld scanners suffer a great deal of abuse as well, he adds, since they can often be dropped. "We've been very happy with Analytica," he says, "They've done a great job."

According to Vikram, the ROI for this deployment was calculated in two ways. One, he says, pertained to "time saved in getting real-time information so that production staff can make good decisions, and the other is reducing the wastage and increasing productivity through continuous and real-time monitoring." Callahan, however, to would not say when he expects Midwest Acoust-A-Fiber to recoup its investment.