Voice-Direct Picking: Pros and Cons

Jan 24, 2007 9:51 PM  By

You’ve probably seen those commercials that extol the reliability of the Verizon Wireless network—the ones with the guy walking all over the world asking, “Can you hear me now?” Every time I see one of those commercials, I picture warehouse personnel talking to anyone in the company who doesn’t work in the warehouse: people in sales, in purchasing–even their supervisors. Often warehouse folks talk about ways to improve productivity in the warehouse, but no one listens.

With voice-directed picking, you won’t have workers walking through the warehouse saying, “Can you hear me now?” Instead, you’ll see them walking through the aisles repeating “check digits” for the location from which they are picking.

Voice-directed technology is not as new as some may think. It has been used in U.S. warehouses for more than a decade now, and it has substantial benefits.

With voice-directed picking (VDP), spoken picking instructions come from the earpiece of a headset worn by each picker. A microphone mouthpiece then enables the picker to talk back to the wireless computer worn on his belt. The wireless computer, in turn, relays data to the warehouse management system (WMS).

Vendors of voice-directed systems will, of course, tell you these systems are great. As a consultant, I tell all my clients who are evaluating these systems that the system will only be as good as the people running it. The wrong people working the right system will produce the wrong results.

What’s right about VDP
Many distributors want any Joe off the street to be able to walk in and become productive within minutes—not weeks or months—no matter whether he speaks English, French, Japanese, or Spanish. And one of the benefits of voice-directing picking is that it can be used within the same warehouse by people who speak different native languages. Native Spanish speakers can hear picking instructions in Spanish and respond to those instructions in Spanish. Pickers who speak English can hear English through their headsets.

Another benefit to voice-directed picking is its hands-free/eyes-free use. This isn’t the case with scanning technologies. Being hands-free is a big advantage. Many radio-frequency (RF) devices are frequently damaged when workers pick pipe, for example. Eyes-free means the user is focused on the product and the location and not on reading instructions from or keying digits into the RF device, or for that matter, reading a pick ticket. Hands-free/eyes-free also means fewer accidents on the job. RF devices are frequently damaged by forklifts.

Eyes-free is also significant because most picking errors happen in RF and paper environments when the device is being returned to the holster. For example, the picker scans location number one, returns the RF device to the holster, and then looks up and picks the product from location No. 2. Nonetheless, most warehouses that utilize RF devices have more than 99 percent accuracy rates. The slight percentage increase in accuracy when converting to voice-directed picking will only have a recognizable impact on the bottom line in high-volume distribution centers — not in a warehouse with 300 orders per day. Organizations have gone from 99.2% accuracy to 99.7% after implementing VDP software. This accuracy increase is significant in high-volume distribution centers, where it can reduce the number of errors by 70,000 or more orders a year. This slight percentage increase in accuracy won’t have a recognizable impact in a low-volume facility, however.

Industry experts will tell you that you can train warehouse personnel on voice technology much more quickly than in a paper or scanning environment. This is true, but they’re really speaking in terms of training the system and not the individual. Of course, individual pickers still need to be taught the warehouse layout, just as in a paper or scanning environment. And you still have to teach pickers the product, unless you are using UPCs with RF barcode readers 100% of the time.

Unfortunately, very few warehouses actually have a training program. Most use the “follow Jim around” training method: The new picker is told, “Follow Jim around, and he will show you what you need to know.” But how did Jim learn? Who knows what Jim is teaching the new guy. Just because Jim is the best picker doesn’t mean he is a good trainer.

When comparing voice technology and RF scanning, productivity improvements are the biggest benefits mentioned by industry experts. In an RF scanning environment, pickers spend approximately 15% of their picking time using an RF terminal. If each picker picked an average of 100 orders a day at 3.5 lines per order in an RF scanning environment, eliminating that RF terminal time means that with voice-directed picking an average picker could pick approximately 52 more lines each day. With 10 pickers, you could reduce your workforce by one and still pull as many orders each day.

Here are a few other stats to consider: 55% of a picker’s time is spent traveling to and from product locations. In a distribution center with a WMS and RF devices, pickers spend 70% of their time walking to the location, taking the device out of the holster, keypunching, and putting the device back into the holster. Only 30% of their time is spent with your most valuable asset: inventory.

What do these stats tell you? I hear them saying, “Focus on the layout of your facility, and don’t be so quick to buy the newest thing.”

Purchasing any technology for your warehouse is only the beginning. Vendors and consultants can flaunt these statistics because warehouse logistics are continually improving. Once software is purchased, operations managers begin to realize just how messed up the warehouse is. Then they begin making improvements to the layout, the training, and the people. When the vendor comes back and asks, “How is the system we sold you doing?” the response is, “Great!” In actuality, the system may very well have been the catalyst to start improvements that could have been made without the new software.

And now, a word about consultants
It shouldn’t take implementing voice-technology software for managers to begin listening to warehouse personnel. Your warehouse folks may not be as articulate as the “experts.” They may not be able to quote facts and figures. But they know something more critical than any industry expert, including me: They know your product. They know your warehouse. And most important, they know your customer.

A consultant is nothing more than an antiquated version of voice technology. Consultants listen to your people because you don’t, and they attach a quantifiable value to the issues so that they will be addressed more quickly.

Consultants provide an analysis of the problem (what you consider complaints from your people) and provide you with an estimated return on investment for solutions to the problem (what you consider a waste of money when suggested by your people).

Yes, a consultant can provide unbiased input, but your people are the real experts if you will just listen to them. Don’t be like the owner who told the picker trying to provide feedback to a problem, “If I were listening, I would hear you loud and clear!”

René Jones is the founder of headquartered in Burbank, CA-based Total Logistics Solutions (www.logisticsociety.com), a warehouse efficiency consultancy.

Related articles:

Now Listen to This: Voice-Direct Picking

Wireless Picking: Now or Later?