Ocado warehouse is powered by 1,000+ 4G-connected robots
Ocado has revealed details of its automated warehouse, which uses more than 1,000 robots that are remotely controlled using the 4G unlicensed spectrum.
The online supermarket retailer claims that this is the first time the wireless protocol has been used for warehouse automation and said that the technology guarantees a connection ten times per second to each of the robots roaming around the warehouse, which are all working within a 150-metre radius.
The protocol works in the licence-free spectrum and also has the potential to be used for other purposes in the future including Internet-of-Things applications, vehicle-to-vehicle connectivity for smart cars, air traffic control systems or large-scale industrial systems.
Ocado said that controlling and locating over 1,000 robots in such a small area posed some difficult challenges.
Initially the project aimed to use Wi-Fi to maintain radio contact with the robots but most Wi-Fi access points can only support a maximum of 256 concurrent clients, which wasn’t sufficient for the scale of the project. In addition, the more robots that were attached to the system, the greater the latency between them and the control point.
The system developers considered using a series of interlinked Wi-Fi access points that were limited to 80 robots each. But because they were constantly moving around the facility they would need to roam between access points, which proved unreliable and led to latency of at least 300ms which impacted upon the command and control of traffic.
Creating such a system also proved complex and expensive and the planning and installation work required for each warehouse was significant.
Ocado teamed up with Cambridge Consultants to develop an alternative solution which eventually led to the 4G system currently implemented.
“It was clear early on that no technology existed which would do what Ocado needed,” said Tim Ensor, head of connected devices at Cambridge Consultants. “That meant they needed to create a completely custom solution to achieve the required performance – but do so in a way that had a manageable risk profile and in the minimum amount of time. They engaged us to help them achieve this.”
“Our expertise in 4G system development and familiarity with available platform technology allowed the joint Ocado and Cambridge Consultants team to develop a solution very quickly and with minimum risk.”
“We created a system based on the principles of 4G but which can support 1,000 devices from a single base station – over 10 times more than is usually possible. At the same time, we needed to ensure it met the requirements of operating in licence-free spectrum. It is the first time this has all been done with 4G technology.”
The system can be easily deployed anywhere in the world and could also be used to control fleets of semi-autonomous vehicles at sites such as factories, construction sites and airfields.
Ocado said it was now looking at how to improve the system by making it smaller while increasing processing power.
In May, Labour MP Stella Creasy said that robots and automation were threatening many traditional jobs.