Sundermann learned that if a pallet was not where it was supposed to be, EastPack's forklift drivers simply took the next available pallet and flagged the first as missing. As a result, the company was unaware of how many pallets it was losing. The challenge confronting GS1 and EastPack, therefore, was twofold—to identify every pallet and its contents, and to ascertain its exact location. The required margin of error in determining location was less than half a meter—otherwise, one pallet could be mistaken for another.
Australian
RFID hardware supplier
Peacock Bros. provided a system that could achieve both goals. "To identify the correct pallet, we put an
EPC Gen 2 RFID
reader with
antenna on the forklift," Sundermann explains. "The pallets have an
RFID tag transmitting on a
UHF frequency between 865 and 868 MHz. When a pallet is picked up, the tag is read and the contents identified. A height
sensor also determines if the pallet was stacked at the top or bottom of the pile."
|
|
An RFID reader and antenna are mounted on each forklift's backrest.
|
To determine the pallet's exact location, Peacock Bros. also developed signs printed with unique 2-D bar codes identifying that location, then placed the signs on the ceiling of the storage houses, and installed a digital camera on the forklift. "The camera is pointed to the ceiling, and when a pallet
tag is
read, the camera takes a digital snapshot of the bar code on the ceiling," Sundermann says. "It decodes the bar code and provides the exact location." This information is then instantly transmitted to EastPack's inventory management system via a wireless infrastructure.
Before installing the new system, GS1 and EastPack conducted a proof-of-concept test. "We were very confident in the RFID system, so most of the testing was of the location system," Sundermann says. "But kiwifruits do have a high concentration of water, and we had to be sure that it did not interfere with the UHF tag and reader."
|
|
A height sensor on the forklift detects whether a pallet is placed at the top or bottom of a stack.
|
EastPack launched a pilot in July 2007, equipping five refrigerated storage rooms with pallet tags and a small number of forklifts with RFID interrogators and cameras. The system's accuracy exceeded 90 percent, the company reports, and the ceiling-mounted bar-code signs enabled pallets to be identified to within 20 centimeters of their exact location.
"It worked so well that EastPack decided on a full rollout rather than a phased rollout," Sundermann says. "As testing had finished in November, and the fruit season began in March, it was a challenging schedule."
According to Smit, the system was in place by mid-March. Early results have been promising, she says, and the company is confident the system will pay for itself in time. "Once we get this project bedded down, we may even look at expanding it into other areas," she states. This could include tagging field bins used to bring fruit to the packing houses. In addition, the company might also utilize the RFID system to track forklift movements to improve efficiency, as well as to assess cool-storage utilization to more effectively stack pallets.
READERS' COMMENTS
Optically Enabled RTLS
The RTLS system utilized by the Kiwi Fruit company in New Zeeland is a very innovative optically enabled system from Sky-Trax, a company in Newcastle, DE. It has the ability to geo-locate to inch level accuracy and, when combined with RFID, provides a 'scan-free' putaway and retrieval capability that is as cost effective as it is elegantly simple. In the absence of RFID, a forward facing CCD devise (camera) can also decode optical symbologies or even use OCR to identify the objects being transported (pallets of Kiwi fruit in the article). GENCO has this technology deployed in a 328,000 square foot facility just south of Atlanta and is planning further rollouts of the technology to additional sites.
Posted By: P. Rector 5/22/2008 at 1:59:00 PM