Wheeled robot helps Hermes to unload boxes from containers
26 November 2024 
The parcels company Hermes is the first company in Europe to use a wheeled robot to help it unload boxes from containers onto conveyors. The robot has relieved human workers of an arduous task, especially in summer when the temperatures inside containers can soar.
A fulfilment centre in Germany operated by the giant parcel and delivery company, Hermes, is using a wheeled robot to unload packages autonomously from trailers and shipping containers, and onto a conveyor system. The robot – a Stretch machine from Boston Dynamics – can unload around 500 packages per hour, each weighing up to 23kg.
The application, at Hermes’ Haldensleben centre, is the first time that Stretch has been deployed commercially in Europe.
Last year, Hermes’ parent, the Otto Group, announced a strategic partnership with Boston Dynamics under which it plans to deploy the case-handling robot at more than 20 sites by 2025 (as well as letting its Spot robot dog roam more than 10 sites to perform inspections). The initiative marks the first large-scale deployment of both types of robots by the same business.
The Otto Group is a €16bn e-commerce and logistics conglomerate with 100 companies – including Crate and Barrel, and Bonprix, as well as Hermes – operating in 30 countries. It also operates one of the most popular e-commerce platforms in Germany.
The Stretch robot moves on a wheels and has a single arm with seven independent joints (degrees of freedom). A smart gripper on the end of the arm uses vacuum suction cups to grasp packages securely. The multiple joints give it the dexterity to move boxes in tight spaces inside containers.
The compact, wheeled base allows the robot to move inside narrow containers, while an onboard vision system detects where boxes are located in real time so that it can calculate the best way to grip them, and in what order. After an operator drives Stretch into a container and runs a safety check, the robot starts to work autonomously.
“The operator essentially presses ‘go’ and Stretch begins moving boxes all on its own,” says Boston Dynamics’ product manager, Andre Brueckner.
Telescopic conveyor
The robot first detects the front layer of boxes, as well as the walls and ceiling of the container. Its arm then grabs the first box and spins around to place it onto a telescopic conveyor belt that protrudes into the container, while the vision system is already deciding which box to grab next.
Because the robot runs on battery power, it is decoupled from any power source. As Stretch advances deeper into the container, it communicates wirelessly with the telescopic conveyor, telling it to extend to follow it in – or reverse out – as needed.
“The robot is automatically communicating with the conveyor belts,” Brueckner explains. “That means that as Stretch pulls forward, the conveyor belt also pulls forward. If Stretch has to pull backward for any reason, the conveyor belt will also move backward automatically.”
One capability needed for the Hermes application was for the robot to place boxes on the conveyor with their shipping labels facing sideways, allowing scanners to read them.
“This is important because basically the entire line upstream is automated and there are scanners that rely on the boxes being placed this way,” explains Boston Dynamics project engineer, JoJo Winsor.
The robot has been designed to handle a variety of cases. As well as picking boxes from their front surface or top, it can pick boxes from their side, allowing the gripper to get more suction cups onto the largest surface area available, and to handle heavy cases more easily.
“Stretch is able to calculate which side is the most optimal to make a stable pick and stable placement,” Winsor explains. The robot “can pretty much handle any type of cardboard container, boxes with graphics on them, boxes of different colours, boxes with some level of damage – or bulging even,” she adds. “It can handle some of the heavier cases on the high end of what a one-person lift would be at this site.”
The robot uses lidar (light detection and ranging) to create a virtual “fence” on either side of the conveyor. If anyone crosses this line, it stops immediately to avoid potential injuries. “That creates a safe interface between Stretch and the people who are working in the warehouse,” says Winsor.
Child’s play
Hermes employee Marcel Günther, who processes inbound freight for the company, says that learning how to operate Stretch felt like child’s play. He was impressed that a robot of this size can handle packages so delicately. “Learning Stretch was fairly simple and easy for any tech-savvy person to operate,” he reports. “Stretch handles the boxes as any normal person would, with the same care and sensitivity.”
Günther adds that Stretch is also a tremendous benefit when the volume of inbound parcels fluctuates – at Christmas, for example – and Hermes may have to scale up the unloading process at short notice. “It’s like a second man for us,” he says.
Stretch also avoids employees having to work in tough conditions, especially during summer months when metal shipping containers can become extremely hot. Stretch can work in both hot and cold extremes for extended periods without a break.
“Health and workplace safety is a real focus,” says Brueckner. “Keeping operators out of the dark, the cold, and hot containers is really important.”
It took less than a week to install the robot at the Hermes site. It typically takes two days to certify staff to work with their new mechanical colleague. “The operators have all been really engaged and really excited to work with the robot,” Brueckner reports.
Stretch is helping the Hermes logistics centre to maintain high safety standards in accordance with German national standards, as well as European Union directives regarding occupational safety and health in the workplace. Tomek Pauer, a project manager in the Otto Group’s supply chain management arm, says that the robot is tackling the gruelling job of unloading heavy cases so that employees can take on more valuable assignments.
“Stretch really supports us in a very labour-intensive process in the warehouse,” he adds. “The adaptability of Stretch to our boxes and our processes has been very impressive so far.
“The Otto Group is actively shaping the future of logistics, and being the first company to implement Stretch in our warehouse proves that we are on the right path,” Pauer says.
Hermes is also using Boston Dynamics’ four-legged Spot robot at three of its sites to collect thermal images, sense vibrations, read analogue gauges, and detect air and gas leaks ultrasonically. Spot’s ability to operate autonomously also provides safety by monitoring fire exits and identifying small structural changes in storage racks. “Spot is supporting us with different maintenance and security tasks,” Pauer reports. “It improves worker safety, reduces unplanned downtime, and cuts energy costs.”
Pauer and his team are planning additional tasks for both Spot and Stretch in the near future.
