As one of the world’s largest third-party logistics (3PL) providers, German company Arvato considers engineering and automation part of its DNA. Arvato’s sprawling campus in Louisville, Kentucky provides supply chain management, warehousing, and fulfillment services for B2B and B2C clients. This means moving tons of inventory through a campus covering approximately 3 million square feet.

So when Arvato’s Louisville staff went looking for a robotics system for one facility on that campus that could unload freight with greater speed and safety, Boston Dynamics’ Stretch robot stood out. Stretch is a first of its kind mobile robot designed specifically to unload boxes from trailers and shipping containers, freeing up employees to focus on more meaningful tasks in the warehouse. Arvato acquired its first Stretch system this year and the robot’s impact was immediate.

“Overall, the perception of Stretch has been very positive,” said Rachael Miller, Senior Director of Operations at the Louisville site. “We know that Stretch won’t replace our workforce, but allow us to upskill our workers to perform more meaningful warehouse tasks. Such tasks include conducting more cycle counts in our warehouse, helping to reconcile those counts, working in our forward logistics, fulfillment activities, and performing quality checks for outbound orders. Stretch has also helped with planning unload times for our trucks. We’re starting to use the data to understand where we need to improve.”

“We had a vision for completely automating a carton from loose-loaded in a container all the way to the outbound process. We already had the scanning and systematic pallet building and sortation. Stretch was kind of that last puzzle piece that we were missing to have a true automated loose-load unload solution… It allows us to improve the back end, the sortation, with just a little bit of our logic change, and we’re able to really achieve higher throughputs than we ever imagined.”

Alex Rees, Arvato’s Senior Project Manager of Automation and Innovations

Solving the Loose Box Problem

The search for a robot began two years ago when Miller’s team was trying to address the challenge of unloading “loose” boxes. To maximize space, haulers generally stack boxes floor to ceiling inside containers rather than secure them on pallets, which would be moved by forklift. As a result, approximately 80 percent of the loads arriving at the Louisville site are loose, requiring associates to unload the boxes by hand.

“We had a vision for completely automating a carton from loose-loaded in a container all the way to the outbound process,” said Alex Rees, Arvato’s Senior Project Manager of Automation and Innovations. “We already had the scanning and systematic pallet building and sortation. Stretch was kind of that last puzzle piece that we were missing to have a true automated loose-load unload solution. Stretch can unload everything that we bring in, in a loose-loaded form. It allows us to improve the back end, the sortation, with just a little bit of our logic change, and we’re able to really achieve higher throughputs than we ever imagined.”

Standalone System More Flexible

The idea of a robot unloading boxes isn’t new, but what sets Stretch apart is the fact it is mobile and entirely self-contained, requiring no power or air lines for operation. This mobility significantly reduces infrastructure costs and training time for Arvato employees. In fact, Stretch is so easy to use, employees required only a few days of training.

“It was probably the easiest implementation we’ve had as far as workforce training goes,” said Rees. “The first two or three days we set up Stretch with the installation team from Boston Dynamics. After that, we got right into training our operators and instructors. I would say within a matter of hours, everybody was able to fully drive Stretch.”

Stretch’s base takes up the same floor space as a standard US pallet. Four omnidirectional wheels allow operators to maneuver Stretch in any direction using a handheld controller. Once Stretch is driven into position within a trailer, operators run a short safety check, press play, and watch Stretch spring into action.

Handling Any Box

Stretch has a single robotic arm with a gripper at the end consisting of several rows of suction cups. The suction cups can be turned on and off independently of each other, in order to get a maximum vacuum seal on any box. This is especially useful for boxes that have openings at the top or those that incur some damage during transit.

Stretch’s advanced vision system detects the front of all boxes in a container, and the robot makes decisions in real time on which box to pick and how to do so. Once Stretch grips a box, its arm carefully places the box on a conveyor belt that will carry it further into the warehouse.

“Stretch can work with anything that’s a box,” said Spenser Brouwer, Director of Customer Solutions and Integration at Boston Dynamics. “As long as it’s shaped like a cardboard box, Stretch can handle it. Even damaged boxes or boxes that are deformed.”

Virtual Safety Zone

Unlike the robots with six-axis arms that Arvato has used, Stretch (which has a seven-axis arm) operates at Arvato without a safety cage. To keep employees out of the powerful robot’s workspace, Stretch uses light detection and ranging (lidar) to create a virtual safety zone with outer and inner perimeters. When someone crosses the outside line, an alarm sounds. If they cross the inner line, Stretch immediately shuts down.

“The safety system is very robust,” said Rees. “Nothing can get anywhere close to the Stretch system while it’s operating.”

Stretch Improvises

Rees has been particularly impressed by Stretch’s ability to think on the fly. He said Stretch takes its time when picking boxes that have shifted in precarious ways. The robot handles them as carefully as employees would. In one memorable incident, Stretch noticed a box had become stuck on the conveyor belt. The robot stopped what it was doing, gave the box a gentle nudge to send it on its way, then resumed its work.

“That really showed machine learning and decision-making similar to what a human would do,” said Rees. “It’s always taking into account so many different variables in general. It might take a few cartons from the left first, to open up more room so it’s easier to remove the cartons from the right as it’s spinning around and placing the boxes on the conveyor. It’s pretty spectacular.”

New Features a Boon

Within the last year, Boston Dynamics has added several new features to Stretch that have improved its accuracy and throughput even more. The first guides Stretch to place boxes in a manner that conforms with upstream automation, such as automated storage and retrieval systems (AS/RS) within the warehouse. Another feature, called multipick, enables Stretch to grasp multiple smaller boxes at the same time, dramatically increasing the speed at which the robot unloads a container.

“The multipicking has really enabled us to achieve higher throughputs, especially with our smaller, lighter cartons,” said Rees. “It can even multipick some of the heavier cartons that our manual unloading team wouldn’t be capable of doing. It can combine two 16-pound boxes as one 32-pound bundle, whereas our manual unloading operations would never try something like that. It would be a little bit too bulky and unwieldy for them to do.”

Boston Dynamics has also worked with major manufacturers to enable Stretch to wirelessly control telescopic conveyors, so they extend and follow the robot further into the container as it progresses, or retracts as the robot backs up. Many companies now offer Stretch-ready kits in which the robot can plug directly into the conveyor system via a simple cable.

More Metrics, Better Planning

Stretch provides instantaneous metrics regarding the number of cases it has unloaded and at what pace. Rees said he has seen what Stretch is capable of, when the robot operated at a clip of 1,200 boxes per hour for some time. Because Stretch’s unload times are so predictable, Arvato can build in additional capacity to its schedule, especially during peak seasons when the timing of inbound truck deliveries can become erratic.

“Seasonal planning is very critical to Arvato operations,” said Miller. “There are often unknowns in the supply chain. With Stretch being very consistent on its unload rate, we can plan additional capacities where we need them. We can also plan for off hours where we may not have a scheduled shift in place, with just one operator putting Stretch into a truck.”

The Missing Piece

Arvato is eager to invest in emerging technologies, including vision systems, automated guided vehicles (AGVs), and autonomous mobile robots (AMRs). Stretch is that missing piece that will enable Arvato to offer clients automated solutions from end to end.

“Arvato is the most technology driven 3PL logistics provider,” said Rees. “We really invest heavily in our robotics and automation because we know that’s what it’s going to take to move us into the future and to stay competitive and to have an advantage over the other logistics companies out there. The workers really love having Stretch as a colleague. In fact, I’ve heard a few of them say that Stretch draws a short straw every day and is the one that has to go into the container to unload the boxes.”

Want to learn more about how Arvato is using Stretch? Join us for a live fireside chat on Wednesday, November 20, 10:00 AM EST.