Overcoming polybag challenges with robotic piece-picking and image-based barcode reading solution
Processing returned items to be placed back into inventory is something many retailers and e-commerce providers wrestle with. Cognex and Soft Robotics helped a large German apparel and accessory retailer automate their manual re-inventory process which helped them improve profitability and increase efficiency.
Automation solution eliminates manual process with 99.9% accuracy
What are three words that strike fear into retailers around the globe? Return. Merchandise. Authorization.
One of Europe’s largest retail companies was struggling to get returned apparel and accessories back into inventory for resale, an all-too-common problem in the age of e-commerce. According to recent statistics, more than 30% of e-commerce purchases are returned, compared to the less than 9% return rate brick-and-motor stores see. Refusing to accept returns from customers is not acceptable because those same consumers are 92% more likely to purchase again from a retailer with a liberal return policy.
Reinventory operations are difficult for many reasons. In the European retailer’s case, a third-party service provider received, inspected, polybagged, and barcoded the returned goods and shipped them back to the distribution center in large, pallet-sized boxes. Reaching for items at the bottom of these large boxes is a challenge for warehouse workers.
Another challenge is that reinventory is less profitable than fulfillment for retailers. Reinventory volume also tends to be highly seasonal, but sales promotions can randomly impact return volume throughout the year. Due unpredictability and higher -cost factors, returned goods are more often either donated or destroyed rather than reinventoried.
The German retailer needed an automated solution: a vision-guided robot with a scan tunnel for a polybag bin-picking operation.
Polybag Barcode Challenge
Single-use polybags are the preferred packages for apparel and related accessories, but they pose unique challenges for automated materials handling and sortation systems. Since they are floppy, it can be very hard to consistently present the barcode on the bag to a barcode reader for successful reading.
To fully understand the problem, engineers from Soft Robotics Inc. (SRI) spent time as manual laborers working the reinventory process. “I can tell you it’s not a super-exciting job, and it’s difficult because the boxes are huge,” explained Craig DeMello, senior applications development manager at Soft Robotics. “You’re always reaching to grab a bag, then searching for the barcode on the bag to present to the reader.”
Soft Robotics provides robotic automation solutions to warehouses and distribution centers, with applications ranging from packaging to order fulfillment. The company’s full-stack, piece-picking solution, SuperPick, combines an ultrafast 3D vision system with proprietary SoftAI™ path-planning algorithms and soft-grasping technology to deliver unprecedented flexibility and scalability for bin-picking applications.
To automate the process for the European retailer, DeMello knew he would use SuperPick to grab the slippery and reflective polybags in combination with powerful image-based barcode readers capable of consistently deciphering partial, distorted, or damaged codes to meet the customer’s requirement to read more than 99.9% of the polybagged goods.
Reading the Polybag Barcode
Using the Soft Robotics’ SuperPick bin-picking solution to pick and transfer the bags was only part of the challenge. The polybag’s barcode still needed to be read and transferred to the inventory system.
After picking a polybag, the SuperPick robot drops the bag on the first conveyor. The system is designed to capture barcodes at various points along the path of the conveyor and chute system. There are three sets of dual DataMan 470 series fixed-mount barcode readers which are mounted along the conveyance route to capture barcodes on the top, side, as well as underneath. The DataMan readers can accommodate the full width of the conveyor and detect both large items such as winter coats as well as polybags containing small items, such as a single pair of earrings.
Developed for high-throughput logistics applications, the image-based DataMan 470 series includes a high-resolution camera and advanced barcode reading algorithms, providing some of the fastest, most robust, and most accurate 1D and 2D code reading available today.
If the system successfully reads a code and enters the item back into inventory, the polybag proceeds down the final conveyor to the distribution center. If the code isn’t read, the product is recirculated onto the cleated conveyor for another try. If the product is recirculated due to missing barcodes, it is then removed from circulation and sent for remediation to maintain accurate inventory counts.
No Way It Can Read That
“We spent a lot of time developing an automated way to passively flatten the polybag for multi-axis code scanning,” explained Austin Harvey, a senior product manager at Soft Robotics. “But even then, we would be watching the system and say, ‘There’s no way the [DataMan] 470 is going to read that code.’ But it would. And still does 99.9% or more of the time.”
Soft Robotics programmed the DataMan readers and optimized performance to achieve the customer’s 99.9% read rate. In addition, they used Cognex Real Time Monitoring (RTM) technology to view code reading results and trends for actionable insights to diagnose and resolve barcode issues during beta testing. In production, the system has run at an average of 500 units per hour, roughly equal to what manual labor can process. “The first hour, the worker can outpace the robot, but after that the worker slows down. The robot also doesn’t take breaks or have shift changes. And it’s during this time that the robot is able to meet or exceed what manual workers were able to accomplish using the old system,” said DeMello.
Rapid Response Translates to Faster Time to Value
Throughout the project, both DeMello and Harvey said they were amazed at the level of support and the quick responses from Cognex.
“To achieve the 99.9% level of accuracy our customer demanded, every angle of every reader needed to be carefully considered. We had Cognex engineers in our building regularly to help us understand the nuances of the scanning technology which allowed us to get the most out of each scanner. As a growing company, we pride ourselves on being fast and nimble to quickly respond to client requests. We needed something that operated at high speed, but we also needed it quickly. Cognex moved with us at the speed we needed,” said Harvey.
According to DeMello, the reinventory sorter induction solution has exceeded expectations for polybag handling and is now being considered as a fulfillment bin-picking solution as well as a return and reinventory solution.