Computer-driven, paperless warehouses and distribution centers run far more efficiently and accurately than those based on manual, paper methods. That's especially true in labor-intensive activities such as order picking.

Enter pick-to-light technology. It uses lights to identify pick locations and LED readouts to tell the orderpicker the quantity required. The result is rapid order handling, productivity increases of 50% or more and nearly perfect accuracy.

Furthermore, the 'pick' in pick-to-light also can become 'put.' Reverse the handling steps in traditional picking, and it's a put-to-light system.

'Basically, put-to-light is used for order consolidation,' says Ed Romaine, director of marketing, Remstar (800-639-5805). 'It involves consolidating orders for a specific store or locations within a store. Items for a store order are put into bins in carousels or into lanes of reverse flow rack.'

Specific bins in a carousel or lanes of flow rack do the accumulating by store, by store department, and even by individual aisles in a store, explains George Feigley, manager of logistics information technology, Siemens Dematic, (616-913-6200). 'More refined put systems consolidate and then facilitate delivery of a tote directly to a specific aisle in a store,' he adds.

Pick-to-light systems have a history of proven usage going back 15 or more years. Put-to-light systems are just a newer use of the same technology.

Put systems are very hot applications, some vendors say. 'It's a huge market now for order consolidation,' says Tom Coyne, CEO, Diamond Phoenix (207-784-1381). 'About forty-five to fifty percent of our business is put-to-light systems,' adds Siemen's Feigley.

Light-directed technology applies to manufacturing too. Here, 'the need to pick small parts accurately and quickly makes pick-to-light important,' observes Remstar's Romaine.

Among applications are those with parts that need to be picked for side-by-side assembly of different product models on a single line at Modine Manufacturing.

Dell Computer uses the technology to ensure proper parts selection to build PCs to individual orders, says Ralph Henderson, national sales manager, Kingway Inca Clymer Material Handling, CAPS Division (603-772-2070).

Other computer makers rely on light-directed kitting of parts for assembly of PCs and laptops to specific configurations, says Stephen Legg, president, Real Time Solutions, an FKI Logistex company (510-985-6300).

The vast majority of pick- and put-to-light uses are found in distribution centers, however. Speed in handling orders, very high pick or put accuracy rates, ready application to existing storage technologies, hands-free operation, and ease of training are key reasons.

'A major weakness of manual, paper picking is that walk and search time kills high productivity,' says Kingway's Henderson. Pick-to-light, however, cuts walk/search time in half, he says. Moreover, 'there typically is at least a 40 to 50% gain in productivity over paper systems.'

Individual company productivity gains 'will depend upon how well the DC was managed before putting in pick-to-light,' cautions Siemen's Feigley. Yet he has seen productivity rise by 50% in many cases and by 400% in a few situations. 'It's all across the board,' he says.

'The biggest paybacks from pick-to-light are in piece picking those SKUs with high volumes,' suggests Feigley.

High accuracy rates, moreover, 'are the hidden bonus from the technology,' Feigley declares. End users can expect to achieve 'at least a 99.9% accuracy rate.'

With accuracy so high, one step prospective end users of pick- and put-to-light should take is determine what it costs to fix manual picking errors, suggests Diamond Phoenix's Coyne.

Another key benefit, Feigley adds, 'is that the picker doesn't have to make any decisions or do any searching.' Pick-to-light software can be coupled with warehouse management software. Together the two systems do all of the deciding, he explains.

In fact, running the pick-to-light system is only the tip of the software iceberg. 'Pick-to-light system software provides users with a rich database that you could not get and easily use with a manual picking system, says Kingway's Henderson. Software permits 'a manager to calculate in a very short time how best to deploy his people,' he adds. In addition, the software helps decision making on how to balance the work loads on busy days.

Storage systems already in place need not be scrapped, moreover. 'You do not need to do a lot of re-engineering to implement a pick-to-light system,' Coyne adds.

Displays can be added to existing storage/staging systems. Included are non-powered as well as powered systems, such as shelving, standard rack or flow rack, horizontal and vertical carousels, and vertical lift modules. Mobile carts with picking directed by an onboard wireless terminal/scanner are divided into compartments with pick-to-light displays, moreover.

'Yet if you are considering a pick-to-light system,' Coyne advises, 'take the opportunity to analyze your business processes to see if additional storage and handling technology might further improve operations.'

Much the same advice comes from Real Time Solutions' Legg. He cautions against 'adding just one island of automation.' Instead, 'it's usually a mixture of intelligent technologies that will get you up to maximum productivity.'

Minimal training—measured in minutes—is needed to learn to pick or put in one of these systems, Legg suggests. 'Fifteen minutes is all it takes for a new hire to climb the training curve,' maintains Kingway's Henderson.

'Training is incredibly easy,' adds Diamond Phoenix's Coyne. Ease of training is important, he adds, for the many businesses that rely on seasonal labor or that employ workers who might have difficulty understanding English.

Click on the icon to read about managing productivity and maintenance with put- and pick-to-light system software.

Click on the icon to read about Modine's manufacturing facility that delivers in sequence engine cooling units for individual Jeep Liberty models.



Click on the icon to read about White Systems' put-to-light system.

Click on the icon to read about Remstar's horizontal carousels.