Chad Johnson had no formal background in agriculture or robotics when he started his Omaha, Nebraska-based robotics company Grain Weevil with his son in 2021.
“It started out as a challenge,” he tells AgFunderNews. “A local farmer and a friend of ours saw a robot that my son had made for a completely different purpose, and he challenged my son. He said, ‘If you can build that thing, build one to keep me out of a grain bin.'”
Farmers have to go into their grain bins a few times a year to break up clumps of grain that may have formed and address other issues. It’s hot, hard work that’s dangerous enough to have inspired a film, the thriller-drama Silo.
The local Omaha corn growers association happened to be screening this film when Johnson and his son built their first working robot, which they displayed at the event and got “hundreds of comments and questions,” says Johnson. One viral video later and it became evident that this was “going to be a bigger project than just a fun little thing for my son to do.”
“Our mission is ‘no boots in the grain,'” he adds. “When we can accomplish that, I think we can really make a big impact on farmer wellbeing.”
With grain bins, ‘accidents happen’
Silo, a film about a teenager trapped in a grain silo and the community that must save him, may be a fictional thriller, but the dangers of grain bins are all too real for many.
Around two dozen people in the US are killed each year in grain entrapment incidents. Flowing grain, created when the auger is running, acts a lot like quicksand; a person can become completely buried in grain in a matter of seconds, causing suffocation.
One might ask why there’s a need to enter a 50-foot-tall grain bin in the first place. Usually it’s to address problems related to spoiled grain, which can happen when there’s too much moisture present for too long. Besides increasing the chances for molds to grow, spoiled grain also clumps together forming vertical walls or “grain bridges” that can collapse and engulf a person.
Hence, the Grain Weevil robot, which the company says can help producers to salvage some of this grain without a person ever having to actually go inside the grain silo.
One of every five people that die in grain bins each year is under the age of 20, says Johnson. “Usually, the younger, more energetic kids get thrown in there, and then accidents happen.”
Suffocating in grain is just one danger. Falling from the grain bin or losing a limb to one of the augers are others. “One of the things that surprised me most was that at any given time, 8-10% of farmers in the United States have farmer’s lung, which is a lung disease caused by breathing grain dust,” says Johnson.
‘Our robot really has to make a return on the investment’
The Grain Weevil robot can do everything a human with a shovel would, from breaking up grain crusts to leveling grain and spreading out other materials that can cause problems in grain bins, says Johnson.
“We can make storing grain much more efficient to have the biggest impact on the farmer. Wellbeing is the freedom of not ever being in [the grain bin].”
Once loading the grain bin is done for the day, the robot is placed in the bin, where it scurries across the grain, inspecting the grain breaking up any clumps.
“The more you run [the robot] the more you ensure that there are no crusts forming,” says Johnson. “It also works really well as you start to bring grain out. [The robot] can move those sidewalls down into the center sump, for example.”
He says the first version, dubbed “the workhorse,” can be used multiple times per year in each grain bin and can manage roughly 500,000 bushels of grain per individual bin. More than that and he recommends having two robots in each bin.
Version 1 of the Grain Weevil has a camera system and a remote controller and is designed to be operated by a human. Johnson says that while it does have autonomous capabilities, this version can’t operate on its own yet. A forthcoming model will have that capability.
While saving lives and limbs is Grain Weevil’s top mission, at the end of the day, the robot “still needs to be an efficient tool,” says Johnson.
He says Grain Weevil’s biggest competitor is “the strong-willed farmer with a shovel” that doesn’t believe a grain bin accident will happen to him or her.
“Our robot really has to make a return on the investment. That’s been a big focus of ours: making sure that the work the robot does is valuable.”
Midwest focus and 2025 commercial launch
Grain Weevil initially participated in the Combine program, a well-known incubator based in Lincoln, Nebraska. During Johnson’s son’s senior year of university, they won the Lemelson MIT student innovation prize, which he says “was a huge honor and got us a lot of publicity. Everything just started to roll out from there.”
In May of this year, Grain Weevil raised a $3.5 million seed round from Homegrown Capital.
Starting this fall, Grain Weevil will partner with Midwest US farmers to provide the robots as a service. The company is targeting the second quarter of 2025 for the first commercial release of its robots.
Johnson says the company is also in the midst of running trials at commercial grain facilities, which have “very similar challenges, just more demanding challenges.”
For now, Grain Weevil will focus on those Midwest states before broadening its reach to other regions and crops.
