Technologies to Support Advanced Picking
Connect, Autumn 2007

Choose systems to complement your picking style

As revealed in High Octane Warehousing, the August 2007 report published by Aberdeen Group, best-in-class companies are twice as likely as their peers to implement picking technologies to enhance their advanced picking methodologies. The goal? To increase efficiency and reduce recurring warehouse labor costs—of which picking can account for more than 50 percent.

Once orders reach the pickers there are three principal picking technologies designed to improve efficiency and accuracy. Radio Frequency (RF) Scanner, Pick-to-Light and Voice Directed Picking technologies can be used individually or simultaneously. All enable real time transaction monitoring, says Dave Gealy, senior consultant with FORTE.

“Real time transaction monitoring permits real time replenishment, reduces stock out conditions and can indicate correct fit when restocking a location. While all offer productivity gains at comparable cost, proper application is critical—and situation dependent,” he observes.

RF Scanners—both stationary and hand-held—offer the first step toward labor efficiency gains by replacing paper pick lists. RF works effectively with all the picking methodologies, and is often used in conjunction with the other picking technologies. “When capturing lot or serial numbers, SKU selection can be directed with a Pick-to-Light or Voice system, and then scanning captures the barcode versus having to speak it or read a very small font on a label,” says Gealy.

On the downside, hand-held units are not hands-free. For highly seasonal businesses, a company would need to invest in the right amount of equipment for peak periods, but during non-peak times that equipment sits idle. Establishing a second shift to use the same equipment twice in a day is a workaround.

Pick-to-Light is a hands-free, light-directed system that displays the quantity of SKUs to be picked in a specific location. At its most effective, a properly structured Pick-to-Light system can reduce labor by up to 40-50 percent in certain instances, particularly when it replaces a paper-based picking system, says Gealy. Used in static racking applications, Pick-to-Light modules can also be integrated into both horizontal and vertical carousel systems.

The technology is best suited to Zone picking, because in a typical setting, only one worker uses the system in a zone at a time. This makes it difficult to apply to Discrete Order Picking because it could create a traffic jam of pickers waiting to get into the same area. A related technology, Put-to-Light, is ideal for Batch picking as it can be applied in a dynamic packing process at the order consolidation point. This application has been applied effectively within some retail fulfillment operations for store replenishment.

With most warehouses finding that 20 percent of their SKU volume represents 80 percent of their workload, applying a Pick-to-Light system in a one-light/one-SKU configuration to just those 20 percent of SKUs generates maximum cost effectiveness. The other 80 percent of slow-mover inventory can be set up in a one-light/multiple-SKU configuration. While this mitigates expense, accuracy can be compromised with the slow-movers, Gealy warns, so apply both easily-read shelf labels and proper slotting techniques to minimize the impact.  

Also hands-free, Voice Directed Picking technologies can also be effectively employed with all of the picking methodologies. Since it is not tied to a sole location, the per-unit cost of Voice technology decreases relative to the number of SKUs in a facility. The technology’s multilingual capability also makes it appealing for facilities whose workforce may not speak or read English.

Additionally, Voice systems can be leveraged to direct putaway and replenishment activities. While many warehouses use RF for these activities, a company moving from a paper-based system could consider implementing a Voice system only, Gealy notes. Successful Voice picking, however, relies on minimal speech requirements. Operators should be able to use check digits rather than repeating a lengthy location number for maximum benefit.

Also, as with hand-held RF units, every picker must be outfitted with a Voice module—a potential problem for highly-seasonal businesses. Likewise, a second shift can solve that dilemma.

Conclusion

Ultimately, the technology you ultimately select should follow the picking methodology you elect to apply, recommends Gealy.

“The appropriate solution is really situational,” he says. “Depending on where you are with your business, consider an evaluation by either internal or third party experts to determine what you need.

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