The online retailer Ocado is developing robots that could reduce its reliance on people to pick and pack groceries for shoppers.

In plans filed in an application to the US Patent and Trademark Office, Ocado describes a system that operates by using two types of robot mounted on a frame above the stacks of merchandise, removing the need for aisles to let people and machines travel around a warehouse. Taking out the aisles would mean Ocado, which delivers Morrisons and Waitrose groceries, could fit more goods into a smaller space, potentially improving efficiency and reducing costs.

It would also reduce the need for people to operate vehicles that move products around.

The company said: “Ocado is always looking for ways to enhance its customer proposition through the development of industry-leading and proprietary technology. As a result, we file a number of patents each year but we may not choose to utilise everything that we patent. As the business grows in scale, we will continue to grow our workforce with a focus on providing the best and most efficient service to our customers.”

Automated warehouses have been in use for decades and Ocado already uses a variety of robots in its operations. Even the movement of the people working in its warehouses is guided by technology to ensure they work efficiently.

But existing systems based on removing containers from closely aligned stacks require mechanisms so expensive that they are rarely used, according to Ocado’s patent application. It says its new system uses two independently operating robots to “remove a target container quickly and with minimum use of resources”.

Ocado is investing heavily in technology as it tries to improve the efficiency of its operations. The company, founded by three former Goldman Sachs bankers in 2000, delivered its first profit in February after 15 years of investment in technology and warehouse systems.

The move into the black came after it signed a deal to deliver groceries for Morrisons. The company now wants to license and sell the technology it employs in its warehouses and distribution network to other retailers overseas.