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A robot that can peel lettuce takes us closer to automating delicate farm work

A robot that can peel lettuce takes us closer to automating delicate farm work


Machines are still learning to be as dextrous as human hands

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Migrant Workers Farm Crops In Southern CA
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There are lots of barriers to automating agricultural work. The cost of robots is one and the difficulty of integrating them into supply chains is another. But a particularly big stumbling block is just how clumsy machine labor can be. That’s why new research from Cambridge University showing a robot that can peel a lettuce is a small but significant step forward.

Harvesting lettuces is time-consuming work. The vegetables grow close to the ground, have to be cut from their roots by hand, and the outer layers peeled off before packaging. There are automated solutions that help speed up this process up (one machines drops lettuce heads into bags; another cuts multiple heads at a time) but they only take care of part of the harvest. It still requires nimble human hands to do some of the work.

This new research from Cambridge University’s Department of Engineering shows that robots might take over soon though. In the video below, you can see a modified Sawyer bot picking the outer leaves off a head of lettuce. It’s slow but it does the job.

Interestingly, unlike other work we’ve seen improving robot dexterity, this doesn’t rely on any research breakthroughs per se, but instead combines existing robotics and AI elements into a new pipeline. Machine vision algorithms are used to identify the stem of the lettuce; a robot arm nudges it into the correct position if its off-center; and a 3D-printed suction nozzle then peels off the outer layer of leaves.

The team behind the solution, which is described in an aptly named paper “Achieving Robotically Peeled Lettuce,” say this system could also work for other vegetables.

“Lettuce leaf peeling is an interesting robotics problem from an engineering perspective because the leaves are soft, they tear easily and the shape of the lettuce is never a given,” said Cambridge University’s Luca Scimeca in a press statement. “The computer vision we have developed, which lies at the heart of our lettuce peeling robot, can be applied to many other crops, such as cauliflower, where similar information would be required for the post-processing of the produce.”

However, this robot is still going to need some upgrades before it hits the fields. It’s slow, taking 27 seconds to peel each lettuce (compared to just a few seconds for a human) and sloppy (it successfully removes the outer shell only 50 percent of the time). Still, the future is coming, and faster than ever.

Read more: Economists worry we aren’t prepared for the fallout from automation