RFID tags and barcodes are still the most common and effective warehouse management systems for gaining real-time insight into a company’s inventory control, but experts say there are a number of things to consider when deciding which technology to use.
For example, it means not choosing RFID automatically when barcodes will suffice, according to C. Dwight Klappich, an analyst with the Stamford, Conn.-based research firm, Gartner Inc. “If barcode’s cheaper and easier, then barcode’s the right thing,” Klappich said.
Why RFID is not always the answer
RFID, or radio-frequency identification, is the newer, more rapidly evolving technology, in which information is transmitted wirelessly from a tag to a scanner, and then processed in a database. RFID tags usually hold more information and can be read at much longer distances than barcodes without requiring “line of sight” between the tag and scanner. Barcoding, on the other hand, is a generally more stable, predictable means of capturing data that has been in use for nearly three decades. The barcodes themselves continue to evolve, as in the case of two-dimensional (2D) barcodes, which can encode more information in a smaller space.
Most of today’s warehouse management system (WMS) software has the ability to manage data captured with either technology.
RFID is not the end-all that some thought it would be in the technology’s early years, according to Klappich.
“If you look at the advent of RFID -- the advent of people talking about using that for warehouse management -- it was really to save one more second in how fast you would be able to scan a box,” Klappich said. “It’s lost luster, because people realize it’s often just as easy to scan a barcode as it is to have the RFID. Barcode works, and it’s cheap.”
Choosing RFID over barcodes makes more sense with expensive products like plasma TVs, computer servers and aerospace parts, where the cost of a tag is inconsequential compared with the cost of the item, Klappich said. RFID also makes sense with items such as flooring rolls, which are large and bulky and would need multiple barcodes, he said.
One of the other primary concerns with RFID is that it is more difficult to use than barcode scanning, according to Bert Moore, director of communications and media relations for AIM (Warrendale, Pa.), an association of automatic identification and mobility vendors.
“Even if the technology were plug-and-play, the implementation is not,” Moore said. If not configured properly, RFID “will give you useless information at the speed of light.”
For one, users must survey their site for interference. Electrical devices like welding equipment and conveyor motors can cause “serious interference” with RFID readings, and products that contain liquids or metal can interfere with the frequencies of the tags, which also cannot be read around corners, he said.
Users also need to make sure the overall RFID configuration, as well as the tags themselves, undergo rigorous testing. Companies should never design an RFID system based on the spec sheet, Moore said. On paper, it may look as if a tag can be read from 20 feet away -- but that may only be in pristine environments. The more realistic scenario might be closer to seven feet.
It’s important to be realistic about RFID, Moore said. “It’s not the greatest thing since sliced bread. It’s just another tool.”
Voice-directed warehouse management
While barcode scanning and RFID tags are tried-and-true warehouse management staples, other alternatives, such as voice technology, are growing in popularity, Klappich said.
Voice technology allows workers to pick orders verbally by using a wireless, wearable computer with a headset and microphone, all of which communicate with the WMS. The technology can also be used for goods receiving, pallet put-away and stock checking, according to the website voicepicking.com. One benefit of voice technology is that companies no longer have to print and attach labels.
“Voice used to be relegated to places where you couldn’t use your hands, like a guy picking ice cream in a freezer, stuff with big mittens and coats,” Klappich explained. “The technology’s gotten inexpensive and ubiquitious enough that we’re seeing people use voice. Voice is growing, much more than in the past. People are operating their entire pit processes with voice.”