When clothing retailer Gap Inc. needed to redesign its Fishkill, New York, distribution center in 2017, it tasked EuroSort with the job. Gap Inc. also required to finish the complete overhaul with limited time before the holiday shopping season. That required automation technology with the speed and efficiency to handle complex supply chains.
While many material handling and intralogistics processes have widely accepted best practices, many challenges remain. One trouble spot involves items that are dubbed “non-conveyable” — usually small, lightweight items that are flexible and rounded in shape. Because the Gap distribution center ships a large amount of clothing and accessories, these items have always presented a unique challenge. Effectively transporting non-conveyables is a continual challenge for material handling and sortation systems, especially in e-commerce applications.
EuroSort can put more destinations in the same footprint with sorters that are simple to maintain and operate at a cost significantly less than competing products that promise the same kind of throughput. “As a result, the technical demands on the automation and control system to realize the new split tray sorters were intense,” says Scott Fry, VP of Operations at EuroSort.
To reduce equipment footprint, EuroSort targeted the network architecture and I/O systems as areas for improvement because the company’s sorters are gigantic, stretching hundreds of feet long. Complicating matters for EuroSort, legacy networks, and most industrial Ethernet systems couldn’t effectively connect field devices on the widely distributed networks needed by their clients. Network cycle times were also limitations, particularly when an array of sensors was installed as far as 200-ft away.
“Because most available I/O systems rely on a low-performance sub-bus for the backplane to connect hardware modules, like our previous supplier, we couldn’t just run wires to distributed I/O modules. We had to connect the devices all the way back to a main panel,” says Jeff Zerr, Advisory Controls Engineer at EuroSort. “After much research into modern industrial Ethernet systems, our attention turned to EtherCAT. The simple fact that the EtherCAT protocol and all its features are preserved across the I/O hardware backplane to all individual terminals throughout a line instantly neutralized these limitations.”
Because of flexible topology characteristics and the ability to distribute I/O across long distances using IP67 equipment-mounted and IP20 DIN rail-mounted hardware, the EtherCAT industrial Ethernet system has been the EuroSort networking standard since 2013. EtherCAT was also selected for its ability to interface with other protocols still used in the field, such as EtherNet/IP, PROFINET, DeviceNet, PROFIBUS, and AS-Interface.
“We often have to connect with new and old equipment from other manufacturers, so we leverage EtherCAT gateways from Beckhoff Automation to establish connectivity wherever needed,” Zerr says. “This led to a closer look at control hardware from Beckhoff, which later became our standard.”
The new control and networking architecture faced some challenging EuroSort projects right away. One of the pilot applications for the new split tray sorter had around 600 destinations and over 400 trays. It also required more than 2,000 I/O points, which were networked over EtherCAT. Subsequent split tray sorter applications were much larger, with over 11,000 I/O points. Here, EuroSort leveraged High Density (HD) EtherCAT Terminals, which offer up to 16 channels in a 12-mm housing. The field-mounted EtherCAT Box modules also proved useful to eliminate the cost, space and materials otherwise needed for numerous enclosures to house I/O stations. The EtherCAT I/O connects many devices in the sorters, such as sensors, solenoids, and variable frequency drives (VFDs). “This all-inclusive connectivity promotes lower costs and a smaller equipment footprint for our customers,” Fry says.
EuroSort uses TwinSAFE technology to network machine safety devices in every sorter equipped with the controls. TwinSAFE I/O and Safety over EtherCAT (FSoE) cover numerous e-stops and pull cords spread across material handling lines. “The more safety devices you have and the more spread out they are, the more it makes sense to have networked safety,” Zerr says. “When a EuroSort customer needs to add a safety function, it’s easy to add it no matter where the equipment needs to go. We also get the added benefit of built-in EtherCAT diagnostics, so TwinSAFE just makes sense.”
“A major reason Beckhoff continues to see significant growth of EtherCAT technology in intralogistics is because there are no restrictions on network size and topology,” says Doug Schuchart, Material Handling & Intralogistics Manager at Beckhoff Automation LLC.
Today, EuroSort relies on the compact CX2040 Embedded PC with 2.1 GHz Intel Core i7 quad-core processors and 4 GB RAM to run PLC, safety, and HMI on one device. EuroSort connects the embedded PCs to compact CP2907 Control Panels with 7-in. screen to display the HMI. For local data storage, the CX2040 also accommodates CFast memory cards up to 160 GB. Maintaining a compact footprint, this DIN rail-mounted automation controller measures just 144 x 99 x 91 mm and has a backplane connection to the EtherCAT Terminal system. This preserves the full performance and functionality of the protocol to every I/O point and back to the main controller.
Programming for all aspects of the EuroSort split tray sorters, including PLC, safety, and high-level communication, is handled in the TwinCAT 3 engineering environment. “TwinCAT 3 offers a good mix of tools for traditional PLC programmers and computer science-oriented programmers alike,” says Zerr. “Engineers can continue to program with ladder logic if desired, but many are seeing advantages to structured text and function blocks. Also, the TwinCAT 3 integration with Visual Studio is a boon for EuroSort. Team Foundation Server has helped our programming teams collaborate on code, stay organized and keep track of all project revisions and changes.”
EuroSort has migrated to different Beckhoff Embedded PC types over the years based on CPU requirements but has been able to keep all programming in the same free TwinCAT 3 engineering environment.
Considering the ability to take on non-conveyables, equipment footprint reductions, and higher system performance, the benefits of the EuroSort split tray sorters have already piled up for Gap Inc. The company has achieved 100% faster scan times and increased accuracy of PC- and EtherCAT-based sorters. Once Gap Inc. began using the EuroSort split tray sorters in a new fulfillment center, order fulfillment accuracy went up 2%.