Flexibility: The hallmark of today’s automated goods-to-person installations

Goods-to-person is blowing up. If you feel like you’re seeing and reading about growth in goods-to-person automation installations at every turn, you are not alone. This growth is being driven by e-commerce and omni-channel. E-commerce distributors need to fill more one- and two-line orders in compressed timeframes with a dwindling and aging labor market. Plus, omni-channel operations that fill orders for multiple channels—brick-and-mortar stores, wholesalers, home deliveries and parcel shipments—need to apply the appropriate goods-to-person solution to match the outbound order’s requirements.

Technologies once applied to store slower-moving, broken case inventory in a compressed footprint—such as automated storage and retrieval systems (AS/RS), shuttles and horizontal carousels—have evolved to offer benefits beyond space savings for investment justification. New developments in those systems, along with new mobile robotic solutions, give operations more flexible installation and application options.

The latest developments  
Gone are the days of an eight-figure dollar investment for a single AS/RS storing every stock keeping unit (SKU), with idle space left for future expansion, says Bill Leber, director of business development and marketing at Swisslog Logistics. Instead, systems have become more modular to support anticipated growth. That allows for more modest investment in an installation that meets today’s needs, but can easily scale up.

“Today’s installations are in the seven-figure range, and many times less than $5 million,” adds Leber. “No one technology can do it all; we’re seeing more hybrid systems with different types of goods-to-person automation in a single facility. You can match each technology to different inventory profiles and handling characteristics to create the right total solution.”

Leber also attributes the uptick in goods-to-person installations to their increased visibility in the market. “The technologies have become more mainstream and less of a high-risk investment,” he adds. “And, the cost of capital is extremely low, which makes net returns on invested capital very attractive.”

One of the first solutions offered in the goods-to-person picking realm was mini-load AS/RS, says Ross Halket, executive director of automated system design sales at Schaefer Systems International.

“Concentrating slow- and medium-movers from 20,000 square feet of floor space into a mini-load that takes 4,000 square feet, letting an operation increase pick rates from 80 to 120 lines per hour,” Halket says. “The maximum pick rate for a person is 1,000 lines per hour; a mini-load needs nine cranes to support that rate.”

That’s not to say mini-load (or unit-load) AS/RS isn’t deployed in today’s goods-to-person installations. Rather, most current systems combine multiple technologies to optimize flow—and using AS/RS to store overstock destined for manual and automated goods-to-person picking.

“Instead of delivering to the end of the aisle, an AS/RS automatically replenishes adjacent carton flow rack holding the fastest moving, manual-pick items, and the goods-to-person shuttle systems, too,” Halket explains. “Because shuttles are typically more expensive, they might hold three days of inventory, while 25 days worth is held in a mini-load.”

Matrix, Schaefer’s newest shuttle offering, incorporates multiple lifts throughout each aisle to eliminate end-of-aisle bottlenecks experienced by traditional AS/RS and to speed throughput. “Matrix lets a facility access any SKU from any storage point and deliver it to a workstation at any time, minimizing the number of waiting totes,” he says.

It’s also no longer the case that an extensive installation of conveyor or loop sorter is needed to move the totes from storage to people, says Lance Reese, technical solutions director for order fulfillment at Intelligrated. “Now, shuttles are more agile and come in a range of different flavors,” he says. “Some are carrier independent and can run on different levels, as opposed to being restricted to certain levels of a system.”

Kevin Reader, director of business development and marketing for KNAPP Logistics Automation, agrees, noting multiple shuttle design variations enable a range of uses within in a goods-to-person application—including storage, sequencing and replenishment, while simultaneously managing overstock, picking and returns.

“Shuttles can handle totes and cartons in the same system. We also install single-, double- and triple-deep load handling mechanisms in shuttle systems up to 18 meters (59 feet) high for maximum density with minimal productivity loss, because item locations are that much closer to the pickup and delivery stations,” he says.

Should seasonal spikes occur, multiple shuttles can run in a single aisle, Reader continues, or they can move from aisle-to-aisle and level-to-level. “The variants in shuttle design make these systems highly responsive and flexible to change. They’re also modular. So, if a shuttle breaks down, it can be replaced.”

Robotic goods-to-person picking systems, like Swisslog’s AutoStore and the Perfect Pick from OPEX, also offer handling flexibility and scalability—making goods-to-person automation cost justifiable to companies doing less than $50 million a year, says Jeff Hedges, president of OPEX Material Handling.

OPEX Perfect Pick Video

“Our robotic technology is uniquely flexible and scalable. The number of iBOT robots deployed is based on the throughput rate and storage capacity a specific operation requires,” he says. “Both the system’s footprint and the process can be easily expanded as a business grows, in part because the iBOTs, which can be driven in and out of an aisle in a matter of seconds, don’t require transfers, lifts and conveyors to deliver items to a remote workstation—they deliver directly to the workstation, which is integrated into the storage aisle.”

Kardex Remstar will bring a new technology to the United States in 2016 that will target mid-sized operations with volume handling needs in the 4,000 to 6,000 units per hour range, says Thomas Coyne, regional director and president of North American operations.

“Horizontal carousel goods-to-person picking requires a batch process to get a high level of productivity, but it’s limited to roughly eight orders maximum,” Coyne explains. “Instead, our new system puts 200 to 300 stationary order totes to be picked at one time around a sortation device that brings SKUs to the operator. For operations considering carousel technology, this new system will increase their pick rates enormously at a more easily cost justified investment level than multi-shuttle systems.”

But, software is key to making any goods-to-person system work—that is, ensuring that the required SKUs arrive at the right workstation at the same time the order is ready to be filled, says Mike Khodl, vice president of solution development for Dematic.

“For proper sequencing, the software algorithms have to optimize and correctly build the flow of stored SKUs to the workstations processing the orders,” he explains. “Ours considers SKU velocity and cube, the order makeup that includes those SKUs, and the productivity requirements in terms of target fulfillment rate and order cutoff time.”

Workstations improve operator speed, accuracy
At the person end of a goods-to-person system, workstations are likewise being flexibly configured to maximize throughput and improve accuracy. Workstations and adjacent order put walls (shelves of cubbies that separate individual orders), can be equipped with light-directed pick or put modules to indicate which SKU goes to which order and in what quantity. Some suppliers offer light curtains that verify the number of picks placed in order totes. Others include a large screen to display an image of the item that needs to be picked.

Dematic, says Khodl, recently introduced the off-board Laser Put solution as a lower cost replacement for light-directed picking modules on put walls. “The operator scans the item and the laser projects a beam of light to one or more put destinations. It can also project text on the shelf front to relay a message about quantity,” he says.

For operations filling 5,000 or more orders per day, systems can be engineered to deliver up to 1,400 items per hour to a workstation. Yet, with these rates starting to outpace the ability of a given operator, Khodl says, “we’re offering conversions to robotic picking.”

Further supporting future goods-to-robot picking, says Reader, is integration of vision systems and software technology into workstation operation. “The technology looks at the items, shapes and colors to identify each item, then directs a picker to a unique SKU for picking out of mixed totes. The same approach is now operating in robotic picking and packing cells,” he says.

Companies mentioned in this article
Dematic
Intelligrated
Kardex Remstar
KNAPP Logistics Automation
OPEX Material Handling
Schaefer Systems International
Swisslog Logistics