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How robot pickers are being used to tackle farmers’ Brexit woes

Robots have already been built that can harvest asparagus, raspberries, strawberries, mushrooms and salad as growers grapple with a crippling shortage of overseas workers.

In farms and laboratories across the UK, a growing robotic revolution is taking on the challenges posed by Brexit, Covid and Vladimir Putin.


Agri-robotic systems and technologies are being deployed in fields and greenhouses as engineering attempts to find solutions after a punishing few years for the sector, with hard-hit farmers forced to leave tonnes of food unpicked due to crippling shortages of workers.


Prototypes can already pluck strawberries, raspberries, asparagus, broccoli, lettuce and mushrooms from the soil. But the march of the robots across Britain’s green and pleasant land won’t be overnight; last year, a review for the Government into automation in horticulture found crop-harvesting robots were unlikely to be commercially available until 2030.


The problems, however, are here and now. Farmers and growers have been battered by Brexit, the pandemic and the war in Ukraine, which provided much of the UK’s seasonal workforce, causing a catastrophic drain of fruit and veg pickers and sending costs soaring.


Farmers are now lobbying the Government for an increase in a quota of 45,000 visas for overseas workers, as Home Secretary, Suella Braverman, insisted this week that more homegrown pickers was the answer, despite the Government scrapping its fruitless ”pick for Britain” campaign in 2020.


The University of Lincoln’s professor Simon Pearson, who co-chaired last year’s review for Department for Environment, Food and Rural Affairs (Defra), told i: “Without automation there will be a real issue. Labour shortages are now a global issue, not least demographic of age issues.


“The other option is to move production overseas to where the labour is located but that could then bring environmental issues and food security consequences.


“Or we lose production of key products but that would hit diet and health.”


The past three to five years had seen “encouraging” growth in the range of crops robots could pick, he said, but the first major breakthrough was likely to come from weed-killing bots.


Investment was pouring into robots that use artificial intelligence (AI) to identify weeds and zap them with weapons such as lasers, concentrated light and precision spray, minimising the need to douse an entire crop.


In 2019, there were 63,000 seasonal horticulture workers in the UK, with up to a third working in packing houses, says professor Pearson, who estimates automation would cause a “significant” impact on the numbers of those workers needed, with thousands of vacancies no longer needing to be filled. The effect on picking, however, was harder to predict.


“It would be disingenuous to even guess it. I think what we can say is they will have an impact that we will start to see over the next two, three years – it’d be a slow tail to start with and then it should build,” he said.


“The key challenge now is cost parity. We can’t have a situation where food price inflation keeps going up.


“One of the big drivers is labour price inflation. You’ve got to solve the farmers’ problem, which is harvesting it, and you’ve got to solve the citizens’ problem which is the price of food. Robotics is an obvious win, isn’t it?”


Labour shortages were “just as big as ever” this year, he said, adding he doubted Ms Braverman’s claim that more UK workers could be encouraged to plug gaps.


“It’s not just in horticulture. We’re starting to hear a lot more about worker shortages across the whole of agriculture, dairy farms, beef farms, greenhouses, the whole lot.”


At an industry showcase in the Downing Street garden last week, Rishi Sunak highlighted the importance of investment in robotics, with the Government providing grants for farmers.


Jack Ward, chief executive of the British Growers Association, said using robots to compensate for shortages of seasonal labour would be “the holy grail”.


“We spent quite a lot of time several years trying to get to this point. And we still seem to be several years away from getting to a point where we could declare that the need for seasonal labour no longer exists, because it could all be done by machines,” he said.


“Not just in this country, because across the world, growers face very similar problems. So it’s not just the UK – it’s an international problem.


“The major packers and growers will be looking at it on an almost daily basis as to what more can we be doing in order to reduce our reliance on seasonal labour? It’s the question that every grower will be grappling with.”


The vagaries of the British climate is just one of the challenges facing the use of robotics. Weeks of cold and wet weather, such as parts of the UK have experienced recently, can impact when harvesting takes place.


“If you come to a warm spell, and you’re growing strawberries, suddenly you will see the volume that you’re producing each day increase substantially,” he said.


“And is your robot capacity able to deal with a 25 per cent increase in volume for, let’s say, three days, because the weather changes?”


Scientists at the University of Lincoln are leading research at the world’s first global centre of excellence into agricultural robotics.


One leading strawberry grower in Kent, Clock House Farm, is already deploying robots which use software designed at the university to treat its plants with UV light in order to prevent fungal infection.



Professor Marc Hanheide, who has headed up the university’s Robot Highways project, said the robot, Thorvald, which travels up and down rows of tabletop strawberries at night, has completely removed the need for chemical fungicides to be sprayed on the plants.


While good progress had also been made in designing robots that can harvest crops such as bell peppers, producing them at scale, and raising capital investment to do so, were challenges.


A human was at least “10 times faster” than a robot when it came to picking fruit such as strawberries, but “if you can scale out, nothing stops you from putting 10 arms on a single robot”.


“You need to find the right sort of economic trade off here. How expensive can this robot be when it has this particular rate of operation,” professor Hanheide said.


Nevertheless, he estimates that technology scientists have developed to allow robots to transport rather than pick produce could shave up to 20 per cent a fruit picker’s working day.


And early studies from AI technology which generates forecasts of crop tonnage for farmers in the coming weeks had slashed error rates from 20 per cent to around 7 per cent.


The “B word”, while creating a recruiting headache for growers, was also problematic for scientists.


“Brexit certainly hasn’t helped. What was probably the main worry for us, as researchers, is that the politicians have been promising robotics as the short term solution and that led to a lot of interest,” he said.


“It also created a level of expectation that robotics are going to save the day – they’re going to come round and replace the need for foreign workers.


“And that was, let’s say, short sighted, I would say. Robotics is about hardware in the end, which means stuff needs to be built. And manufacturing hasn’t been our big strength, I would say over many years.”


Dr Belinda Clarke is director of Agri-TechE, a not-for-profit group which brings together farmers and growers with researchers to advance the use of innovation in food production and land management, said the last five to six years had seen an advance from proof of concept to working machines in the field.


“Brexit was seen quite widely as an accelerant of the trajectory that the UK’s automation and robotics industry was already on,” she said.


“Brexit certainly caused some big farm businesses to say right, we really need to invest quite heavily in automation technology and robotics technology.”


Scientists were now bringing a “technological solution into a biological context”, but it may be some years before robots rule the roost on our farms.


She added: “We’re so close, but obviously a lot also depends on private investment into these robotics companies.


“There’s a lot of contingencies impacting the rate at which the robotics industry will reach its necessary maturity for widespread commercial adoption.”


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