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The inventor of the Roomba just launched a weed-killing robot named Tertill

The inventor of the Roomba just launched a weed-killing robot named Tertill


The constant garden bot

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Photo: Franklin Robotics

Franklin Robotics, a Massachusetts-based robotics company with a team that includes the inventor of the Roomba, just launched a Kickstarter campaign for its newest robot. This time it’s not a carpet-cleaning or floor-cleaning bot, but one designed to kill the weeds in your garden.

Called Tertill, the round, 2.5-pound bot uses sensors to identify weeds in a vegetable or flower garden. It then uses a spinning string trimmer to cut off weeds near the ground. But it’s not using any fancy cameras or artificial intelligence to identify weeds. Instead, chief technology officer Joe Jones says, it’s relying on cheap capacitive sensors to determine whether the plants it has brushed up against are tall or short.

“The big problem with weeding is, how do you tell the difference between a weed and a plant that you want to keep?” Jones said in an interview with The Verge. “With a garden, you can recognize the difference between weeds and crops based on size. So anything that’s short enough to go under the robot is considered a weed, and anything taller is considered a plant.” What about short plants that you don’t want Tertill to whack? The solution there is a Tertill-resistant collar you can put around new plants until they’ve grown tall.

An early Tertill prototype built with Lego.
An early Tertill prototype built with Lego.
Photo: Franklin Robotics

It’s a relatively low-tech approach to this kind of land-sweeping robot, and it’s unclear at this point how well it will actually work. The Tertill is also solar-powered, and is supposed to run every day, which its creators say will also help keep weeds from thriving.

But Jones said he hopes the bot will grow smarter over time, and, that if it’s a successful product, he plans to add more features. One feature the team has considered adding is a kind of motion sensor-triggered reaction that would cause the bot to move and help scare pests and rodents away. They might also utilize artificial neural networks to make Tertill smarter. “I used to be quite against neural nets,” Jones said over the phone, “but they’ve won me over.”

Tertill costs $199 on Kickstarter right now, and is expected to ship in March 2018. Jones says that it will likely cost around $300 if and when the Tertill goes into full production.

Jones and his team have also developed Slugtaze, a slug-repellent plant collar

Most recently, Jones and his team were running Harvest Automation, a robotics company focused on moving potted plants around nurseries and greenhouses. Harvest Automation also developed robots designed to work in e-commerce fulfillment centers.

But Jones’ biggest claim to fame is undoubtedly the Roomba, which Jones is credited for inventing. iRobot first started selling the robot vacuum cleaners in 2002, after years of Jones trying to get the bot off the ground (erm, floor). The company has since sold more than 15 million Roombas.

Jones once told New York magazine that the one thing he’s learned about robots is “they always break your heart. One way or another. What you do is try again.”