Food, Farming and Countryside Commission

Small robots

By Callum Weir

Wimpole Estate, Cambridgeshire

Meet Tom, Dick and Harry – a trio of robots. Along with Wilma, the digital brains behind the robots, they could revolutionise the way we farm over the coming decades.

Resembling luridly painted miniature Mars exploration rovers, they are being developed by an agri-tech start up from Salisbury called the Small Robot Company to monitor crop health, seek out and destroy weeds, and plant seeds – and we’re testing them on our National Trust farm on the Wimpole Estate.

We have 370 hectares (914 acres) of arable land that we use for growing cereal crops. Our farm is one of 20 in the Small Robot Company’s Farming Advisory Group, but is the only organic farm, which makes it a challenging test site as we have more weeds – it gives the robot more to learn!

The robot being tested with us at Wimpole is called Tom, and it’s essentially a robotic agronomist. It sets an area to map and travels autonomously up and down the fields, taking photos of the crops and weeds in high resolution. The photos are then stitched together and an algorithm distinguishes what’s wheat and what’s weed, creating a digital map of all the weeds in the field.

The basic premise is that 95% of chemicals used in farming are unnecessary. Imagine that a robot could be sent out into a field to find where the weeds are, and come back with their precise coordinates. Instead of spraying the entire field with expensive herbicide, you only spray or mechanically remove individual weed plants. The same principle applies to the precision application of fertiliser, whereby fertiliser bills could be reduced, as well as the risk of leaching.

The robotic revolution could bring particular benefits to small farms. Instead of investing hundreds of thousands of pounds in an 8-tonne tractor, farmers would only have to pay out a fraction of that for Tom, Dick and Harry. Tractors compact the soil, and unnecessary cultivation damages soil structure and contributes to soil erosion, so soil health would benefit too.

Other, more radical, possibilities also exist. In the future robots might be able to plant different seeds in the same field, allowing strip farming on a much bigger scale. This could move away from pure monoculture – just one variety of crop in a field – which would have many benefits. Take peas and wheat for example – if you can grow both in one field, the peas fix nitrogen into the soil, which helps the wheat grow. The pea flowers attract bees, increasing biodiversity. With weather becoming more extreme and unpredictable, it’s harder to know what will grow well, so having more than one crop improves farm resilience.

Robotics also has the potential to reduce the reliance of farming on fossil fuels. They’re smaller than standard farm machinery, so the robots can be electrically powered, potentially charged by solar panels.

The technology is still in its early days – and it may be 10 or 15 years before this technology becomes mainstream – but trialling new technologies here at Wimpole is very fitting. The 3rd Earl of Hardwick created Wimpole Home Farm in 1794 as a demonstration farm, using the latest machinery to improve efficiencies and increase yields. Today, our goal is to improve biodiversity and soil health, but the spirit of innovation lives on. Watch this space.


Adapted from an article by James Fair in the summer 2019 edition of National Trust Magazine.