Robotic truck unloading gets its due

There may finally be a solution to filling one of the least desirable jobs in the warehouse: trailer unloading. The physically demanding position requires workers to swiftly lift and move heavy boxes out of a trailer, which remains exposed to the elements while on the loading dock—an especially daunting task in places like Florida in July or Toronto in January. Such conditions make the process a welcome application for robotic automation, according to just about anyone who has ever run a warehouse, but until recently the prospect of automating it seemed like a still-distant reality. That has changed in 2023, with the commercial launch of automated truck unloading systems by a handful of robotics companies—a feat company leaders and their business partners say may open the door to industrywide change.

“Warehouse [work] is hard, but being assigned to work inside a container is really tough. It’s not an ideal location to have associates,” says Nicolas de Keijser, director of sales for warehouse robotics at Waltham, Massachusetts-based Boston Dynamics, whose “Stretch” robot has been unloading trucks at a DHL Supply Chain facility since January. “This is a job that associates are happy to [see automated] so they can be reallocated to other areas in the warehouse.”

Brian Gaunt, vice president, accelerated digitalization at DHL Supply Chain, agrees, adding that robotic truck unloading is a game-changer for logistics operations.

“If you think of packages and parcels … our whole supply chain is set up to bring those items into a warehouse to be processed. So there’s wide applicability [for this technology],” Gaunt explains, noting that DHL Supply Chain operates 500 sites in North America alone. “Being able to automate this process is critical to us.”

Technology advances, and a whole lot of trial and error, are behind the DHL/Boston Dynamics story as well as that of Cambridge, Massachusetts-based Pickle Robot, which announced the commercial availability of its unloading robots in March. The technology is helping to improve productivity in the warehouse while also addressing often sky-high labor turnover on the loading dock. Here’s how.

FROM PILOT TO PRODUCTION

DHL Supply Chain and Boston Dynamics started collaborating on warehouse robotics about four years ago as part of a larger effort to automate DHL’s operations. The contract logistics services provider works with a range of technology partners to automate many aspects of its warehouses and fulfillment centers, and has invested about $430 million in automated technology, largely in North America.

“DHL was the first customer willing to take a chance on the first prototype that we had, [which] we built to do work in the warehouse with boxes,” de Keijser explains. “This partnership allowed us to start validating some of our ideas about how to move boxes around.”

Those early efforts led to DHL Supply Chain’s $15 million investment in robots from Boston Dynamics in 2022, an effort that culminated in a handful of truck unloading applications at DHL sites nationwide this year. “Stretch” robots—which consist of a robotic arm, suction grip, and mobile base—unload cartons of product coming into the facilities daily. Using the suction gripper, the robots take packages from the trailer, grabbing them from the top or side, and place them on a flexible conveyor for delivery into the building. The boxes are then scanned into inventory and placed into storage according to the particular facility’s material handling processes. The battery-powered robots work through a full shift on a single charge, unloading up to 500 boxes per hour. One of DHL Supply Chain’s most recent applications is at a dedicated fulfillment facility for workwear company Carhartt, in Canal Winchester, Ohio. The system is in testing there now, with deployment planned for later in the year.

A combination of sensors, cameras, controls, and artificial intelligence (AI) directs the robot’s movements. Its flexible robotic arm can reach boxes throughout the trailer, adjusting to handle boxes of different shapes and sizes (the robots can handle cartons weighing up to 50 pounds), and even reacting to configuration changes: Stretch can recover fallen boxes or easily grasp those that have shifted during unloading, just as a human worker could.

“The robot needs to understand its environment at any given point and then act accordingly,” de Keijser says. “It will see [a fallen box] and [respond] by moving around and picking up whatever fell. There is no interrupted flow, and no human assistance [is needed].”

Two months into the project, the solution was yielding about a 40% increase in efficiency at the Carhartt facility, with Stretch unloading at speeds faster than manual operations, according to Gaunt. Even more importantly, workers have been freed from the tough physical work of trailer unloading and can now perform more value-added activities such as picking and putaway. Some associates have moved on to new tasks such as programming and troubleshooting Stretch as well as other robotic solutions at work in the facility. What’s more, productivity improvements are expected to grow as Stretch continues to learn and improve: de Keijser says he expects the system to eventually unload up to 800 boxes per hour.

Gaunt described the project as transformative, both for DHL Supply Chain and the broader logistics industry.

“It’s nice to see something on a multiyear journey come to fruition,” he explains. “We’re at a state in the supply chain where technology and vision systems have advanced to a point that’s allowing us to take the next iterative step in automation. Previously, we had [cleared a number of hurdles], but advances in AI over the last four to five years have allowed us to take on challenges like this. Industrywise, it’s exciting.”

PROBLEM SOLVED

Leaders at Pickle Robot Co. agree that advanced technology—and easier access to it as costs come down—is what has made automated truck unloading a reality in 2023. Pickle was founded four years ago by a trio of Massachusetts Institute of Technology (MIT) graduates looking to apply robotics to supply chain processes. The company’s name is a play on the word “pick”—the robots are performing picking tasks in the truck-trailer or shipping container—as well as a nod to another food-named company, Apple Computer, whose founders Pickle’s creators admire, according to Pete Blair, the company’s vice president of marketing and sales.

“Most importantly, [the name] is intended to make you smile and make us approachable,” Blair says, pointing to workers’ concerns when they learn that robots are coming to their warehouse. “When they hear there is a Pickle robot coming, that usually puts people at ease. I mean, who doesn't want to see what a Pickle robot is?”

The bright green robot consists of a commercially available robotic picking arm and a company-built base as well as sensors, cameras, and “a ton of software” that allow it to move boxes of different shapes and sizes out of a trailer. The robot grips boxes high up in the container from the top or front of the box, handling up to 60 pounds in any orientation. For those boxes that are positioned lower—either on the floor or toward the bottom of the trailer—the robots can move boxes of 100 pounds or more by gripping them from the top, Blair says. In either case, the robots place the unloaded boxes on a flexible conveyor system that carries them into the warehouse, where they are entered into inventory. He says the robot does the equivalent work of two warehouse associates.

Blair touts the independence of the system as a game-changer as well; because the robots are not tied into a company’s warehouse management system (WMS) or enterprise resource planning (ERP) system, the system can be quickly installed and set to work.

“What we’re doing is handling the physical unload; the inventory upload is a process right after us,” he explains. “Our system does not have to [integrate] with the warehousing systems.”

This makes Pickle robots—like Boston Dynamics’ Stretch, which is similarly independent of a company’s WMS or ERP system—even more of a boon to companies looking to automate processes on the loading dock. Blair cites a roughly 43% average turnover rate for warehousing jobs nationwide, a statistic he says can run as high as 100% for container unloading, according to some Pickle customers. Automating the process solves a huge labor problem, quickly. 

“Ask someone who does importing. It’s not uncommon for people to show up in the morning and [not return] after lunchtime,” he says, citing temperature extremes and the repetitive stress of moving box after box of heavy goods. “It’s an unforgiving job. This [technology] is something people want, and it’s applicable to thousands of dock doors across the country.”

Pickle officially announced the commercial availability of its robots this past March, during the ProMat material handling show in Chicago. At the time, the developer had a handful of implementations up and running across the country, one of which was for a food importer called United Exchange Corp. (UEC), based in Los Angeles. Pickle robots are unloading cargo containers that UEC imports from Asia. The company has been using the Pickle system since last summer, according to Blair, who says he expects business to accelerate as word spreads that truck unloading robots have finally arrived.

“When people hear a robot is coming, there is always concern,” Blair says. “But when we get there and talk to people on the dock, so far, universally, the response has been ‘Thank God, I don’t have to get into that container anymore.’ This is a huge opportunity.”