An Ocado food delivery truck dropping off a family’s weekly shop is a common sight nowadays. Founded in 2000, the British online supermarket has expanded rapidly, disrupting the conventional grocery delivery model by sending out goods from warehouses rather than chain stores. It is now claimed to be the world’s largest online-only grocery retailer – shipping more than 200,000 orders every week.
You may be forgiven for thinking that Ocado is simply an innovator in the grocery market. But Dr Graham Deacon, robotics research team leader at the company, says this is a misconception: “We are a technology company that happens to be selling groceries. We have been pushing the boundaries of automation for some time now.” Ocado’s “traditional” warehouse in Hatfield, Hertfordshire, uses 26km of conveyor belt. When a customer orders goods online several totes – red plastic buckets – are launched on these belts and transported around the warehouse, travelling to the correct points. Periodically they get pulled off and presented to a human picker who can see the order on a computer in front of them and knows which product to pick off the shelves and put in the tote before it is released back onto the main line.
This process has been automated even further at Ocado’s distribution warehouse in Hampshire, which uses swarms of robots to collect groceries. These “bots” skim along rails on top of thousands of crates containing the 47,000 products Ocado stocks. The bots move in planned routes to find the crates required to fill an order, and then deliver the items to a human employee who packs them. This hardware platform uses smart logistics software that runs in the cloud.
However, this is just the beginning of Ocado’s exploration of robotics. The company is involved in two EU-funded Horizon 2020 programmes exploring advanced autonomous robots.
One project, called SoMa, is exploring the use of a robot hand that can pick and pack fruit and vegetables. Deacon says this is the next “natural” step for Ocado. “We have already looked at robots to pick things in our warehouses and can get so far with regular shaped, rigid-body objects but we are looking to pick up as much as we can with robots,” he says. Until now it has been very difficult for robot arms to pick up delicate items such as fruit that have varied shapes.
SoMa is a collaborative research project between the Technical University of Berlin (TUB), University of Pisa, Italian Institute of Technology, Deutsche Zentrum für Luft, Institute of Science and Technology Austria and Disney Research Zurich. It aims to design robotic hands that can pick up fragile objects without much detailed knowledge of the items’ shapes.
The robotic arms should also be capable of exploiting environmental constraints. For example, rather than precisely locating a credit card on a table and attempting to grab it, it would slide the card to the edge of the surface and pick it up, just as a human would.
Ocado is testing a “compliant” gripper – one that can form its hand around an object in the way that a human’s fingers would – that has been designed by TUB. The RBO Hand 2 uses flexible rubber materials and pressurised air for passively adapting grasps which allow the robot to pick up objects delicately. With seven individually controllable air chambers, the anthropomorphic design can perform a variety of versatile grasping strategies.
Owing to its compliant design, the robotic hand is highly under-actuated: only the air pressure is controlled, while the fingers, palm and thumb adjust their shape to the given object geometry. This simplifies control and enables “effective exploitation of the environment”.
Ocado is drawing on this research to study how it might use similar designs to pick up fruit and vegetables. “These are products we don’t want damaged,” says Deacon. “They are never the same shape twice. If I have a bunch of bananas to pick up I can’t have a CAD model – these things have significant variation.”
Once Ocado has a working prototype, which should be at the end of the project in 2019, the next challenge will be how to plan the robot arm’s operations in the warehouse. The company will explore the use of a vision system.
The next Horizon 2020 project Ocado is involved with is even more ambitious. Called SecondHand, it is exploring the use of humanoid, wheeled robots to assist technicians in their maintenance tasks. The idea is that the robot will observe technicians performing tasks, understand what they are doing and offer assistance. The robot might hold a panel in place while a technician unscrews it, or offer the right screwdriver at the right time. It will be voice activated.
The prototype is being built by Karlsruhe Institute of Technology in Germany. It will be delivered to Ocado for use in a warehouse by June, and will come with pre-programmed behaviours such as knowing how to hand over a tool. To achieve this simple task, the Karlsruhe researchers used inertial measurement units and accelerometers to monitor people doing handovers to replicate the movements and weight shifting that occurs.
This project is incredibly complex and is taking a lot of work to ensure that the robots not only respond correctly to visual cues and verbal commands, but also that they react quickly enough to be useful to technicians.
Deacon says: “Robotics is quite an expensive thing to get into. The reason we are doing this now rather than in the future is because we have been able to get funding from the EU Horizon 2020 research programme which helped us de-risk the whole thing. Once Brexit happens this source of funds may well be cut off from companies.”
So what about companies looking to get the benefits of warehouse robots that do not have deep pockets and that cannot get access to lots of R&D funding? For many the solution lies in off-the-shelf products.
Darren Reynolds, the product manager for RARUK Automation, a new company formed by R A Rodriguez, says it is selling the Universal Robot UR10 arm to “every single sector you can think of, whether it be a small family-run company right through to major automotive companies”.
Reynolds says these collaborative robot arms are an attractive option for a first investment in robotics: they run from a 240V supply, require no safety guards, and prices range from £14,000 to £25,000.
Real Digital International, a specialist in digital print communications, has installed a Universal Robot UR10 at its Croydon facility to help with the packaging of mobile phone SIM cards. Previously an operative checked the start and end of each box containing 100 packaged SIM cards. A lid was then fitted to each box before it was inserted into a strapping machine where it received a seal tab. Once sealed, the box was placed on a pallet. Instead, the UR10 robot is placing the lid on a box of packaged SIM cards, turning it 90° and offering it into the strapping machine where it receives a plastic heat-seal security wrap. After exiting on a conveyor, the robot picks and places the box in the correct position on the pallet.
David Laybourne, managing director of Real Digital International, says “the UR10 is easy to programme and offers repeatability of 0.1mm”, which is helpful in maintaining the precise positioning of the pallets each time. As well as automating mundane manual operations, the company says the robot has allowed it to move employees to more varied tasks.
Robots are also coming in useful for firms that would otherwise find it difficult to employ people to work in more extreme conditions. NewCold Advanced Cold Logistics of the Netherlands is using robot automation at its cold stores. Piet Meijs, vice-president of business development at the company, says it would be very difficult to find staff to work in the freezing temperatures in the stores. Increased customer demand means that employees would also have to work through the night – much less of a problem for robots.
NewCold uses fully automated storage and retrieval stacker crane robots to assemble items for delivery from the warehouse, also improving the accuracy and speed of the process. These crane robots travel around on rails controlled by an intelligent computer system.
There are three levels of automation in the cold store. A warehouse management system keeps track of the inventory and handles orders coming in. The material flow controller, called the traffic manager, receives orders from the warehouse management system and informs a crane robot that a pallet needs to be shipped to a specific dock. Meijs says: “It ensures that within the total traffic plan the pallet takes the shortest route and takes alternative routes if there is a hold-up to get to the final destination.”
The PLC is the lowest level of software control. It stops and starts motors and pallets when they hit the correct locations.
Getting the cranes to work in the freezing conditions was no easy task, says Meijs, as the team had to pick special materials and oil for gear motors that can still work at -20°C or lower.
The company has settled on a design that works optimally in these harsh conditions and now NewCold has highly automated cold stores all around the world, including at a site in Wakefield, West Yorkshire. The model has been so successful that the company is just about to add a further 16 automatic crane robots at the Wakefield site to deal with the demand from customers, which include McCain Foods.
The use of automation means that the cold stores have less of a footprint than ones that use conventional forklift trucks. The stores can also be taller as automated systems can climb higher than human drivers are allowed to. NewCold is building a cold store in Tacoma in Washington state that will be 42m high.
Automation also increases the traceability of the product, which can be tracked back to the pallet it was transported on throughout the warehouse. NewCold hopes to improve this by adding ultraviolet labels to products so that they can be traced from the time they are sent from the supplier to the cold store, when they are frozen, and when they are delivered to the supermarket.
Companies are quick to say they are not reducing staff numbers with the addition of robots – Deacon says Ocado has employed more people owing to rapid expansion – but the future of human workers in warehouses remains less clear in the long term.