Food Engineering

The Rise of AS/RS

February 1, 2010
Automated storage and retrieval systems have served manufacturers for decades, but technical advances and practical considerations are making them more appealing than ever before.

Vertical heights well over 100 feet maximize storage space with today’s automatic storage and retrieval cranes, resulting in a smaller footprint and big energy savings in refrigerated warehousing. Source: Swisslog Logistics Inc.


For Cargill Inc., the shift to case-ready meat and customized pallet loads for retailers couldn’t have come at a better time.

In the mid ‘90s, the Minneapolis-based company scrubbed the carousels, buffers and other traditional tools for meat handling in favor of a highly automated system at an Atlanta cut-beef center. Two similar automated storage and retrieval systems (AS/RS) followed, with a fourth scheduled to come on-line in early 2010.

The initiative coincided with demands from major grocers for subprimal cuts that could bypass a store’s butcher shop and go directly to refrigerated cases. As Cargill’s investment and sophistication increased, so did retailers’ demands: mixed loads with product arranged to coincide with a store’s layout became the new marching orders. The sequencing of complex orders would have been ripe for human error and shipping delays with the systems of the past. Now, the company views its infrastructure investment as a strategic advantage that, not incidentally, slashed refrigeration costs and labor requirements.

The dollar value of on-time deliveries and complete orders is difficult to quantify, but powerful forces are reshaping the food business. Maintaining high customer satisfaction can be as critical to a company’s long-term viability as avoiding a crippling recall. Customer satisfaction gets relegated to the soft-savings category of automation initiatives, of course, but the flexibility of AS/RS solutions is making these investments easier to justify in terms of the hard-dollar returns.

Tall cranes moving pallets through narrow aisles is the popular image of AS/RS. Those systems still characterize the technology, but increasingly they are complemented with mini-load systems, automated guided vehicles (AGV) and centralized picking systems. Some pallet-handling suppliers have decoupled rack storage completely from cranes, relying on elevators, row carts and rack moles to store and retrieve pallets in high-density environments.

Pan- and trough-storage systems used in commercial bakeries fit neatly under the AS/RS umbrella, with robotics replacing cranes for the heavy lifting. Weldon Solutions, a York, PA, machine tool shop, made a specialty of these systems in 2003 when it acquired the intellectual assets of Emtrol. Handcarts loaded with heavy baking pans are worker injuries waiting to happen, but factoring in ergonomics into an automation decision is difficult. Even so, this AS/RS application is growing.

“Labor saving was our whole reason for putting the systems in,” Mark Porter, senior vice president of operations at Fort Wayne, IN-based Millie’s Bakeries, says of his firm’s deployment of robotic pan-handlers at five of its seven plants in Michigan, Ohio and Indiana. Three of the plants also have automated trough systems.

Less frequent pan reglazing, more efficient use of floor space and better inventory control are benefits of automated pan storage, but “labor was the sole justification,” Porter emphasizes. “They’re fairly expensive systems,” he allows, but still the company realized a return within three years.

Broccoli arrives at Congelados del Valle’s produce facility in Leon, Mexico. After processing and packaging, the broccoli will be automatically stored in the firm’s –20

Focus on food

Research by the Material Handling Institute of America (MHIA) suggests American industry invests approximately $200 million on fixed-aisle AS/RS each year. The difficulties in automotive in particular and industry in general in 2009 resulted in an off year, though food and beverage was fairly stable, with both new projects and systems upgrades buoying activity.

Reliability concerns are a major deterrent to adoption of the technology, MHIA research concludes, though the existing systems have proven remarkably durable. A crane installed by Swisslog in 1967 remains in service, though the original controls are long gone, according to Bill Leber, business development manager in Swisslog Logistics Inc.’s Newport News, VA, office. Swisslog’s first US food installation was a decade ago at Wawa Dairy, Wawa, PA.

Steve Parsley worked on one of the earliest North American AS/RS installations in the late 1960s, when he was an engineer with Maytag. Reduction of product damage and pilferage helped justify the early installations, he remembers; today, speed, accessibility and control are the drivers, with control manifesting itself as traceability in a food operation.

AS/RS capital investment is easier to justify in today’s food business as companies boost asset utilization by abandoning single-shift operations, says Parsley, principal engineer with St. Louis-based Bastian Material Handling. With customers sometimes requiring daily instead of weekly deliveries, the inventory turns that make the business case for AS/RS looks better.

The AS/RS of today bears little resemblance to the early versions. The ‘60s systems predated relay controls, relying on punched Hollerith cards – Herman Hollerith founded the forerunner to IBM, which used to rely on punch cards in mainframe computers – to mechanically tabulate where pallets were stored. Controls technology is much more sophisticated now, but great strides in system hardware have also been made. “Over the last 10 years, the advancements are unbelievable,” reflects Mark Livesay, business development manager at ESI Group USA in Lancaster, PA. Servomotors, laser positioning and other equipment refinements deliver “faster, smoother running equipment that accelerates and decelerates without spilling or damaging a load,” he says.

Equipment reliability also is much improved, though bad experiences with older systems soured some food companies on the technology. Still, interest is on the upswing, particularly in freezer applications where the reduced amount of steel needed to construct a rack-supported building stretching 40-plus feet high makes the return on investment more attractive. Add in the energy savings from an automated freezer compared to a conventional cube, and the financial case can be compelling.

All AS/RS systems have their strengths and weaknesses, Livesay notes, and the application dictates the best solution. ESI is in the business of building the infrastructure and shell surrounding a warehouse, and while conventional warehouses still account for the bulk of its business, AS/RS is a growing segment. “Before, if you got one or two projects a year, that was a big deal,” he says. “Now you get 15.”

Virtual pallet movement

Faster speeds and smoother motion are visible improvements. A more important advancement is the software that manages the systems. Software capability has defined the technology since its inception: the automation arm of defense contractor Litton Industries created the dominant supplier decades ago. The successor organization is HK Systems Inc., and software development remains a focus.

Full pallet movement will remain the distribution mode of breweries and other large-scale bottlers for the foreseeable future, but distributors and other food segments need systems that can retrieve cases from a variety of locations and assemble them for shipment, says Lonnie Watkins, account executive-beverage distribution systems at HK Systems. Rainbow pallets can be built automatically, but the cost is out of line with the labor savings. Proof of concept has been done on mixed-SKU automation, he adds, though commercialization is years away. But the batch picking and wave planning capabilities of today’s systems already are far superior to traditional sortation systems, and “what’s changing the game is the sophistication of the software,” says Watkins.

Dan Labell, president of Westfalia Technologies, seconds Watkins’ point. “When you get to order fulfillment, you have to rely on simulation,” and order complexity demands simulation models that can work through scenarios before the servomotors begin to whir. With their ability to dynamically locate fast-moving items and rearrange storage locations based on emerging sales patterns, system programs are nibbling on the edges of artificial intelligence, Labell suggests.

Refrigerated storage with deep racks is becoming more common in food applications, and rising energy costs will accelerate the trend. York, PA-based Westfalia recently began work on a second automated warehouse for Congelados del Valle, a Leon, Mexico, processor of asparagus, strawberries and other produce. After cleaning, product is immediately packed and deep frozen. A single crane stores finished goods six pallets deep and nine levels high in Congelados’ newest freezer, for a total of 4,524 pallet positions.

Retrofits of existing warehouses also are occurring, though refrigeration wasn’t needed for Milwaukee’s Gehl Foods, a leading aseptic dairy processor. Only three levels could be built in the company’s existing building, but Westfalia was able to increase density 50%, negating the need for a larger building.

Phased complexity is the path followed at Wawa Dairy. The initial installation involved 16 AS/RS cranes and a warehouse management system to oversee manual and machine operations. Two major expansions have increased automation in the last eight years, including 16 mini-load stacker cranes that sort and access 88,000 individual cases. Swisslog maintains a six-person team on site to manage the distribution system, which serves a network of more than 500 convenience stores.

Systems solutions

The AS/RS supplier community is populated by systems integrators and equipment manufacturers. Regardless of whether they bend the metal they sell, suppliers are emphasizing their ability to deliver solutions customized to manufacturers’ needs.

Grand Rapids, MI-based Dematic Corp. fabricates material-handling equipment used in AS/RS and picking systems, but that doesn’t influence the solutions it designs for food and beverage companies, insists Ken Ruehrdanz, warehouse and distribution manager. “The solution may or may not use some of the technology our company makes,” Ruehrdanz says. “We’re not wrapped around the equipment.”

Like most AS/RS system suppliers, Dematic’s roots are in Europe, where limited space and high labor and energy costs dictate automated warehousing, particularly in refrigerated applications. With their smaller roof surfaces, rack-supported AS/RS cut energy costs 35%-50%, according to Ruehrdanz, and the trend in electricty prices is clearly up.

Retrotech Inc., a Fishers, NY, systems integrator, has commissioned a score of greenfield AS/RS projects, including a recently completed 1.1 million sq. ft. automated DC for Procter & Gamble in Lima, OH. But expansions and system updates are Retrotech’s bread and butter, and the engineering firm touts its ability to rescue older systems from obsolescence by replacing controls and select equipment instead of scrapping an otherwise reliable and effective system. 

Multiple factors are at play in system-implementation decisions, points out Pete Hartman, Retrotech’s president, and rules of thumb can be meaningless when a manufacturer’s strategic direction is involved.  Generally speaking, if product is stored fewer than 15 days, or a warehouse handles more than 225,000 pallets a year, an economic argument for automation can be made. However, operating philosophy may be more important. “If a company thinks their warehouse is someplace to store stuff, AS/RS is not a good solution,” says Hartman. “If they think of it as someplace where stuff moves through, then we can talk.”

Retrotech recently formed a strategic partnership with Actiw OY, a Finnish firm that manufacturers the Activ unit-load material handling system. The partnership is partly driven by Retrotech’s work with P&G, but it won’t alter the firm’s agnostic approach to equipment selection, Retrotech officials insist. With cable-driven carts and deep-lane transfers that can work in rack-supported or freestanding warehouses, the Activ technology does not fit MHIA’s definition of AS/RS. Nonetheless, it delivers the storage density, efficiency and other arguments for AS/RS, albeit without a crane.

Power Automation Systems (PAS), Lathrop, CA, is another supplier who has decoupled AS/RS from cranes. Lathrop also is home to California Natural Products, the aseptic, low-acid copacker that represented PAS’s first North American installation. Horizontal pallet movement is accommodated by aisle-way carts to a row rail cart for deep-aisle storage. Elevators deliver pallets to each level. Wireless Ethernet provides the data highway.

“We can get much higher throughput than a conventional crane can,” with up to 200 pallets an hour per module, according to Josh Berrington, PAS marketing director. “Compared to a 12-crane system, PowerStor has higher throughput and 30% more storage density.”

Custom pallet loads are the norm in Spain, where PAS’s mobile layer-building cart made its debut. Leche Pascual, a dairy that also distributes a range of other refrigerated products, pioneered use of the automation system because of the labor costs and high error and damage rates it experienced with its multi-touch pallet-building operation. An articulated-arm robot travels on board the cart as it moves on rails to 134 pick locations; the robot uses suction grips to build each pallet layer. The cart can build up to 4,000 layers a day, notes Berrington. The system slashed labor costs 70% at Leche Pascual and replaced eight forklifts.

When automation combines with simplicity, the result is new possibilities. Such is the case with SmartCart, an automated guided cart introduced in 2002 by Jervis B. Webb Co. that now is attracting interest from food manufacturers. Instead of embedded magnets or laser guides, the cart is guided by a magnetic tape that can be peeled off the floor and reapplied for a new traffic route, as needed. A variety of attachments increase flexibility further, with forks, roller heads for conveyor interaction and a tow attachment among the options. SmartCart is less sophisticated than an AGV, allows Sarah Carlson, marketing director at the Farmington Hills, MI, firm, but it’s also much more economical. Some reprogramming is necessary when switchng tasks, but the Windows-based software is intuitive.

Webb Co.’s long-time relationship with Daifuku became closer in 2007 when it merged with the Japanese firm. Daifuku America Corp. set up operations in Salt Lake City in the 1980s, following the migration of Japanese automakers to America. According to marketing director Shana Relle, the relationship with Webb expands the breadth of Daifuku’s material-handling solutions for food and beverage.

A component supplier that is shifting toward turnkey AS/RS solutions is TGW-Ermanco, Spring Lake, MI. Mini-load machines are TGW’s sweet spot, and the company recently introduced a single-mast stacker crane that borrows aircraft construction concepts to deliver a lighter, stronger crane that also is more energy efficient. Payloads up to 22 lbs. and heights of 39 ft. can be served.

While storage and retrieval responsibilities for finished goods often are outsourced, many food manufacturers now view AS/RS and related investments as a competitive edge. “One area where you haven’t seen a lot of automation is in 3PLs,” says John Clark, TGW’s marketing director, speaking of third-party logistics providers. Short-term contracts are a barrier: whereas 3PLs in Europe typically have three-year deals with food companies, their American counterparts usually strike one-year contracts, making it difficult to secure financing for capital investments.

For food companies with deep enough pockets and a long-term view, investments in this type of supply-chain efficiency is looking more appealing.

For more information:
Stephen Parsley, Bastian Material Handling, 513-398-0382, slparsley@bastiansolutions.com
Shana Relle, Daifuku America Corp., 801-573-6028, shana_relle@daifukuamerica.com
Ken Ruehrdanz, Dematic Corp., 616-913-5931, kenneth.ruehrdanz@dematic.com
Mark Livesay, ESI Group USA, 717-406-3256, mlivesay@esigroupusa.com
Lonnie Watkins, HK Systems Inc., 262-860-7000, lonnie.watkins@hksystems.com
Josh Berrington, Power Automation Systems, 209-249-1616, josh.berrington@pas-us.com
Pete Hartman, Retrotech Inc., 585-924-6333
Bill Leber, Swisslog Logistics Inc., 757-820-3400 bill.leber@swisslog.com
John Clark, TGW-Ermanco Inc., 231-798-4547, john.clark@tgw-ermanco.com
Sarah Carlson, Jervis B. Webb Co., 248-553-1257, scarlson@jerviswebb.com
Charles C. Gales, Weldon Solutions, 717-846-4000, cgales@weldonsolutions.com
Daniel Labell, Westfalia Technologies, 717-764-1115, dlabell@westfaliausa.com

A storage/retrieval machine trolls racks of bread pans at Pepperidge Farm’s Bloomfield, CT, bakery. The three-tier bins hold 26,000 pans

Pan storage and retrieval trailblazer

In vintage bread plants, the din of pans clattering through mechanical storage-and-retrieval equipment rivals the decibel level of a forge. The noise is muted in modern facilities, thanks in part to the robotic handling systems that are replacing their forerunners.

AS/RS technology rendered mechanical pan-handlers obsolete, though the switch to robotic units had a rocky start. Pepperidge Farm’s Bloomfield, CT, bakery (“Built for speed,” Food Engineering, April 2004) installed a three-tier automated handling system to store and retrieve 12 types of six-strap pans for three lines. The 26,000 pans in inventory far surpassed an earlier version installed in Texas by Emtrol, Pepperidge’s original vendor. Before the equipment arrived, however, Emtrol fell into bankruptcy. The project was in jeopardy until a team led by Weldon Solutions stepped in to install and integrate the system.

Weldon is based in York, PA, also home to Westfalia USA. The fact that both companies engineer and install automatic storage systems is indicative of the diversity of the category: Westfalia focuses on heavy-duty racking systems served by towering cranes moving on tracks in a narrow aisle, while Weldon caters to commercial bakeries, usually with single-level storage systems. Robotics frequently are incorporated in Weldon’s solutions, which include lid tenders and other heavy-duty pick-and-place systems.

The potential for AS/RS in process applications is tremendous, believes engineer Charles C. Gales, Weldon’s manager of automation sales. After bread dough is mixed, a hold time is needed before it enters the makeup line. Troughs with 2,000-lb. dough batches can quickly accumulate and clog aisles, creating a hazardous work environment. Weldon engineered an automated system to store and retrieve troughs as needed. Approximately two dozen have been installed at new and existing bakeries since 1994, including three at Aunt Millie’s Bakeries, which operates seven plants in the southern Great Lakes region.

In-process AS/RS has enormous potential but remains grossly under-developed, says Gales. For that matter, so are Pepperidge-style pan handling systems, he adds. While the number of lines and variety of breads produced in Bloomfield are unusually high, most bakers could benefit from the smaller footprint that a racking system provides. Had Pepperidge Farm opted for the more common single-level system, it would have tripled the storage area and, by extension, the brick and mortar needed to house it.