The farm of Clint Brauer in Kansas, it could be described as that of Uncle Tobia, but with robots.
Along with 1.6 square kilometers of greenhouses, a flock of over 100 sheep and Warren G, a banana-eating llama, at Greenfield there is in fact a troop of ten weed-killing robots weighing 60kg each. What are they doing? They promise to make us avoid pesticides.
Brewer, the co-founder of Greenfield Robotics, grew up as the classic country boy from Pozzettiana memory. He left for the big city, but eventually returned to the family farm. Now it has combined tradition and future, because the farm is also the research and development headquarters for the Greenfield Robotics team.
Ritorno al futuro
When Brauer returned to his agricultural roots, he did so with one purpose: to demonstrate that food could be grown without harmful chemicals. Pesticides can be avoided by embracing practices that respect the soil and the planet. It did so by becoming one of the main farmers who grow pesticide-free vegetables. It sells its excellent products to local markets, grocery store chains and chefs.
It wasn't enough to make a difference, though. A few hectares of vegetable production free of chemicals were nothing. Especially in comparison to the miles and miles of vast arable farmland that make up the majority of farms in the USA.
And this is where robots come into play.
Old and young farmers spend at least 50% of their time (and money) on controlling weeds. Right now, there are three solutions to the problem. None of them are perfect.
There's good old human toil, an expensive and physically debilitating task. It is increasingly difficult to find help because, frankly, almost nobody wants to do it.
There are mechanical solutions, like tractors that pull plows, discs, shovels and motor hoes that kill weeds. But, as farmers have discovered, tillage disturbs the delicate microbial life of the soil, leading to decreasing yields and loss of soil.
Then there is solution number three: herbicides. They're still expensive, but cheaper than labor, and they work. Where's the catch? The catch is definitely there, and it's atrocious.
Farmers overwhelmingly choose the chemical option. A study published last month in the Environmental Health Journal shows that 1,3 billion euros in agricultural pesticides have been used in the US.
Glyphosate, or “Roundup,” is the most commonly used herbicide in the world and the one that most consumers have heard of. It was designated a probable human carcinogen by the WHO cancer agency as early as 2015. The independent research group The Detox Project reports that glyphosate may be an endocrine disruptor and it is unclear whether levels of “safe use ” established are safe in the long term.
Its excessive use has led to "super weeds" resistant to glyphosate which sometimes require even more aggressive and toxic substances, even for the health of farmers.
The Greenfield robotic solution is based on a simple idea: keep mowing.
Simply don't do it by hand anymore, but delegate someone, sorry: something else.
The enemy number one
When Brauer started thinking about which grass to hit first, the purslane orelacea or amaranth was an obvious first enemy. It is the prototype of the nefarious weed: invasive, adaptive and resistant to herbicides.
A single plant can grow over one meter and eighty and produce up to half a million seeds. It spreads easily and farmers must continue to work to get rid of it even after their harvest starts growing, otherwise it quickly takes over.
Come on, weedbot!
Brauer simply discovered that if mowed repeatedly, a few centimeters from the ground, the purslane eventually gives up the fight and dies. Well. There's a problem, though: If you mow a field of black cherries, you're mowing everything. Including, technically, the crop you're trying to grow.
A standard-sized tractor and mower does not fit in soy, corn, cotton or any other wide-brimmed crop, which is typically sown in rows 75 centimeters apart. And a heavy tractor and lawnmower cannot go to the fields when they are too wet or risk being planted there.
Not to mention that to avoid pesticides, to weaken the growth of the weeds and to overcome their rhythm, one should stand there mowing non-stop.
Weedbots, mowing robots, are small enough to fit between rows, light enough to work in muddy fields and, the best part, they can do it alone. Also on the team.
Brauer contacted an old friend, Steven Gentner, founder of RoboRealm, an IT company. Teaching to farm robots seeing the rows of crops was relatively easy.
Large-scale agricultural production is already suitable for robots because it is already hyper-controlled. Large farmers plant straight rows that stretch for kilometers at exactly the same distance.
Weed-proof robots
Each weedbot has a sensor that allows it to detect depth. It can “see” the rows planted in the field stretching into the distance, thanks to computer vision. It can combine this capability with standard row spacing data, and update its location in real time with GPS.
The robot farmers advance
The Small Robot Company is a UK-based robotic startup that produces robots that electrically "hoe" seedlings to avoid pesticides. He obtained funds for 5 million euros. Founded in 2015 with a crew of four robots (Tom, Dick, Harry and Wilma), it almost immediately focused on the problem of weeds.
The Small Robot Company distinguishes between weeds and crops differently than Greenfield. Instead of relying on established crop rows that weed robots can see and follow, it focuses on photographic and scanning technology instead.
The Tom robot begins the process by scrolling through the field and mapping it. This information is uploaded to Wilma. So Wilma tells “Dick,” the digger robot, to get to work,
Dick, who is the size of a small car, follows Wilma's directions and moves across the field at a walking pace, identifying each weed seedling based on previous mapping data.
This solution is more complicated than Greenfields mowers, but allows greater capillarity.
In its first tests in Kansas, the Greenfield team encountered some unexpected obstacles: a shovel. A piece of pipe. A rock. When this happens, the robot shuts down the mower, an off-site operator intervenes and solves the problem remotely. Despite this limit, the prices of weed robots are lower than those of chemical solutions.
That's why Greenfield has raised $ 500.000 in funding for its weed robots, and is in the process of receiving another 8 million.
