Tailored for performance
Apparel maker Desigual's new automated picking and sorting solution may use standard components found in other systems. But there's nothing ordinary about it.
Sometimes, the line between picking and sorting gets blurred. For instance, take a system where sorters divide batches of products into individual orders, and in doing so, perform the order selection duties commonly done by pickers.
If that sounds like some kind of futuristic technology, it's not. Desigual, an apparel company founded in Barcelona, Spain, in 1984, has such a system. The automated setup is designed specifically to meet the demands of high stock-keeping unit (SKU) turnover and changing distribution cycles.
The name Desigual means unique or unequaled in Spanish. The company, whose colorful, fresh designs set fashion trends worldwide, ships some 22 million pieces of clothing annually from its distribution center in Barcelona. The items go out to more than 10,000 customer locations in 114 countries, including the company's own branded stores, Desigual sections in department stores (stores within stores), and a wholesale channel. The facility also serves several thousand e-commerce customers daily. In the United States, Desigual has its own stores in New York, San Francisco, Los Angeles, Las Vegas, Miami, and Minneapolis. Desigual fashions are also sold in many larger Macys stores.
Distributing a multichannel mix from a single facility can be a challenge. The company produces two collections each year—spring/summer and autumn/winter—each with up to 1,000 different designs, including clothing, shoes, and accessories.
For each new collection, the Barcelona facility performs two completely different types of distribution. When a new collection is ready, large shipments are sent to all outlets within a few weeks so that the collection can be introduced worldwide at about the same time. These first shipments of the collection, called "initials," represent very high volumes and are processed within a tight delivery window.
Once the collection begins to sell, the facility shifts gears and sends out "repeats" to restock products on store shelves. The repeat orders, which are a fraction of the size of the initials, are shipped more frequently to ensure stores are kept stocked.
Distributing orders as dissimilar as the initials and the repeats requires material handling systems that are extremely flexible. The systems also have to be able to track the entire inventory with precision and know how it is to be allocated to orders.
After experiencing growth of about 40 percent annually, Desigual's managers realized several years ago that the company's manual distribution processes wouldn't be able to keep up with demand much longer. In 2010, the company worked with SSI Schaefer to design a highly automated system that could handle the diverse distribution tasks required by Desigual's seasonal collections. The design took into account the fluctuating volumes, the high SKU count, and the need to balance workload.
The solution features a one-of-a-kind picking and sorting solution supported by conveyors and automated storage and retrieval systems (AS/RSs), along with sophisticated software to manage it. In combination, these systems allow the facility to select and distribute some 100,000 articles of clothing daily.
"In our old manual operation, it took 100 people to do 30,000 pieces a day," recalls Sergio Castresana, Desigual's logistics manager. "Now, we do 100,000 pieces each day with fewer people. And we have a lot of control, and our service rates are very high."
The facility is engineered to flow goods through the operations with minimal human intervention. Pallets holding uniform-sized cartons of products are stored in a nearby warehouse located about three miles away. The pallets are trucked to the facility and offloaded using pallet jacks. The loads are then taken to a receiving area, where boxes are removed from the pallets and placed onto plastic trays. A tray ID and a box bar code are scanned to "marry" the tray to the product it holds. A worker also opens the top of each box so that the items, which are pre-ticketed, can be easily removed later in the process.
The box is next sent through a banding machine, which places a plastic band around it to add strength and to maintain its integrity so that it won't bulge on the sides. This assures that it will be a uniform size and won't catch on anything as it passes through the conveyors and other automated systems.
Conveyors, supplied by SSI Schaefer Peem, then transport the trays to an AS/RS. This system contains six aisles and 90,000 tray storage locations. The building housing the AS/RS is rack supported and covers 9,400 square meters, or 101,180 square feet. Despite their small footprint, the racks are capable of storing 3 million articles of clothing.
A crane in each aisle gathers the boxes as they arrive and deposits them into the racking, with faster-moving items placed closer to the near ends of the aisles. When items are needed for orders, the same cranes collect the trays and their boxes and deposit them onto takeaway conveyors for transport to the main sorting system.
The boxes of products are delivered to four pick stations that act as induction points for the sorter. The source tray holding the box is automatically scanned as it arrives, and a lighted display above the station tells the worker how many items to pick from the box. Since the tops of the boxes were removed at receiving, the products, most of which are folded garments in polybags, are easily retrieved.
Workers use both hands, quickly alternating, to select items one at a time from the source box. They place each product onto an induction conveyor belt within the station that feeds the sorter. A sensor detects the motion of the worker's hands as items are pulled out of the source box, automatically counting down the remainder needed from that carton and showing that number on a lighted display. This allows for extremely fast picking, as it frees workers from having to worry about color, style, or SKU numbers. All they have to do is follow the prompts. This design makes it possible for just a few workers to select 3,600 pieces an hour from about 900 source boxes, on average.
Once the items needed for orders have been removed from the source box, the box is conveyed to one of two intermediate picking storage buffers located nearby. The two buffers have three aisles each and are served by automated cranes. This area has a total of 10,800 storage locations and can hold the boxes on their trays three deep. The boxes will be held in this buffer until the products are needed. This same buffer is also used to temporarily hold finished customer cartons until they are sequenced to shipping. The cranes serving the intermediate picking buffer can perform 1,400 moves per hour.
The facility's warehouse management system, also provided by SSI Schaefer, coordinates the sorting of items so that all sizes of an SKU are packed together to make store putaway faster.
"When it arrives at the store, it is ready to put on sale," explains Castresana. "This puts the strain on the warehouse, but we would rather do that than put strain on the store, where the labor is more expensive."
Belt conveyors transport the items from the pick stations to the facility's split-tray sorter. The conveyors act as buffers to regulate the flow of goods into the sorter without slowing down the picking process preceding it. The sorter consists of 70 trays moving in a circular train. Upon approach, the items are automatically scanned so the system knows which item will be placed onto a particular sorter tray. About 87 percent of all goods in the facility can pass through the sorter, with the remainder handled manually.
The conveyor carries the product above the sorter, and at the precise moment the assigned tray passes below, the belt rolls to gently drop the product into the tray.
The sorter trays are hinged on the sides and split in the middle, similar to bomb bay doors, so they can quickly open to deliver products into 54 staging chutes located below. As the tray approaches the chute to which the order is assigned, the tray splits, gently depositing the item into the chute. Each chute will gather items from several different trays, depending on the size of the order.
Underneath the staging chutes, conveyors carry order cartons that will ship to stores and Desigual's other channel customers. The chutes act as a synchronized buffer between the sorter and order cartons, with products held within each chute until the carton destined for those goods is indexed below. At that point, split doors on the bottom of the chute open to deposit the garments into the order carton. The cartons will then continue to progress along the row of chutes, with more items added from other chutes to complete the order. In a sense, the chutes provide a secondary level of sorting.
Completed cartons are transported to an area where they are labeled and stapled closed. They are then sent either directly to the outbound docks or to the buffer AS/RS until ready to ship.
A UNIQUE COMBINATION
The combination of the ergonomic picking-induction stations, the trays for sorting, the chutes for staging and performing a secondary sort, and the movement of cartons below allows for very high sorting rates in a very limited footprint. All of these movements are coordinated with sophisticated software that enables the system to perform 9,000 sorts per hour, while managing 4,000 orders simultaneously and utilizing only the 54 physical chutes of the system.
Castresana notes that while this sorter solution uses standard components found in other systems, the components have never been put together in this exact way before. The unique combination serves the demands at Desigual well.
"The sorter is the key point," he says. "We did not intend to discover something new, but this works for us. In the end, the automation was the best solution. It gives us control, security, and the best performance for our demand."
Unique enough to match its name – Desigual.More articles by David Maloney
Join the Discussion
After you comment, click Post. If you're not already logged in, you will be asked to log in or register.
Resources Mentioned In This Article
Feedback: What did you think of this article? We'd like to hear from you. DC VELOCITY is committed to accuracy and clarity in the delivery of important and useful logistics and supply chain news and information. If you find anything in DC VELOCITY you feel is inaccurate or warrants further explanation, please ?Subject=Feedback - : Tailored for performance">contact Editorial Director Peter Bradley. All comments are eligible for publication in the letters section of DC VELOCITY magazine. Please include you name and the name of the company or organization your work for.