Clint Brauer, of agricultural robotics brand Greenfield Robotics, predicts that mechanical robot swarms will one day handle the bulk of agricultural weed control.

“Our guiding mission is to eliminate chemicals. And I think we’re on a path. I know we’re on a path. How long will that path be? I don’t know,” says Brauer, who founded the Kansas-based company in 2018. “We believe that small is the future, and it’s not too distant. You have less ground compaction, and you can get out a little bit earlier than you can with a big ground rig.”

A part of that future that Brauer envisions is already here.

Greenfield Robotics manages a fleet of 25 small, yellow weeding robots that work in Midwest fields. The machines are manufactured in-house, with proprietary software, technology and purpose-built hardware. They weed rows, plant cover crops and add nutrients in-season, among other duties.

“We’re moving very fast,” Brauer says. After contracting with farms on a subscription basis, “the current process is: We fly a drone and map the field very accurately. with civil engineering accuracy. Then, we deploy the robots, and they weed between the rows. They cut the weeds right at the ground. We do that once or twice a season. Most of the time, once is enough.”

The robots, which are 4-feet-long, 2-feet-wide and “not quite waist-high,” move between 2.5 and 4 miles per hour. They’re monitored by a central operations center in Pennsylvania. Cameras are mounted on poles at the back, and they use a combination of sensors and RTK GPS technology to navigate with “sub-centimeter accuracy,” Brauer says.

They’re so precise that they don’t hit the crop. “We’re getting pretty close to where we can count individual plants as we go,” he says.

Batteries are swapped every five hours. The robots can weed between 30 and 100 acres per day. This year, Brauer expects they will cover 30 to 50 fields. Aesthetically, they look like cartoon characters from the Pixar movie “Wall-E.”

“I came up with these. And still, standing at the edge of the field, I’m like ‘What in the world?’” he says. “We drop them off; they fire up and connect; and [we] keep an eye on them from our network operations center. They’re autonomous, and we intervene once in a while.”

Other alternatives

There are other innovations on the horizon. UK-based Garford-Rootwave’s new eWeeding system, for example, kills weeds with electricity. Electrodes are dragged between the rows by a toolbar system. Electricity runs through the plant, using the soil as a return conductor. The plant’s moisture heats up, damaging its walls and killing the weed.

“It desiccates itself and dies within a matter of hours,” says Jonathan Henry, Garford’s managing director. “Using electricity to kill plants, these loose principles have been around for a long time. Extremely high efficacy has been recorded in the trials we have done.”

Henry says the soil and crop are unaffected by the process. Financially, he argues that investing in a machine that can be used repeatedly is better in the long run.

“We think this makes sense because farmers are spending more and more on herbicides,” he says, estimating the price of the eWeeder is “in the range of 50% to 100% of the cost of chemistry only” over a five-year period. The machine would pay itself off in that time.

Robotic sprayer

There are several robotic sprayers on the marketplace, such as Brazil-based Solinftec’s Solix. In its second year of commercial use in the U.S., the Solix uses targeted spray technology, identifying weeds with cameras and artificial intelligence to reduce the use of herbicides by up to 95%, compared to traditional broadcast applications.

The robot also surveys the field at a plant-by-plant level, gathering data and information on crop health, weed infestation and specific pests.

SELF-SUFFICIENT: Solinftec recently announced the release of a docking station, which will allow its autonomous sprayer robot, the Solix, to operate completely on its own for the entire season — without needing to manually refill. (Solinftec)

The brand just announced the release of a docking station, which will allow Solix to operate 100% autonomously for the entire season — without needing to manually refill.

“Each field has unique characteristics that allow for different weeds to appear in the field, depending on the stage of the crop. We designed the docking station to allow Solix to choose the product that will be used based on the recognition of weeds by our artificial intelligence system, Alice AI, enabling the use of specific products for each unique situation,” says Guilherme Guiné, chief operating officer for North America.

The docking station is autonomous, solar-powered and integrated with the Solix platform. The station also incorporates scouting data obtained throughout the growing season to ensure the right products are available for day-to-day executions.

Preparing for future

Greenfield Inc. doesn’t sell its robots. Brauer says that decision was made early on and has slowly scaled with the advancing technology. The company’s efforts are starting to get attention. Chipotle has invested in the vision. And Brauer says they have partnerships with Candidate Pet Food and MKC Co-op, which is the largest grain co-op in Kansas.

Brauer was early to the internet. He compares the current ag tech robotics marketplace to the dot-com era, when an explosion of tech startups came online at the same time. It took a while for front-runners to emerge and the industry to settle.

“It’s early. And I think folks are still trying to understand how this will work,” he says. “One day, all of a sudden, the lightbulb went on. I can distinctly remember it.”

And with how fast technology is advancing, that lightbulb moment might be just around the corner.

“Three years ago, sometimes, you’d turn on a robot and wonder if it was even going to turn on. We don’t have that problem anymore,” Brauer says. The other day, for example, his team dropped off two robots at a field in Georgia. They were up and running within 5 minutes, with someone observing them from Pennsylvania, and they didn’t run into any problems.

The technology, Bauer says, “is accelerating really quickly.” He says there isn’t any piece of technology that’s holding them back.

“There is not anything left that we do not understand at this point. I could not have said that two years ago,” he says. “All of the pieces are there. We’ve built the ones that need to exist.”