Driverless cars could be Silicon Valley’s next big breakthrough, but self-driving tractors might beat them to the punch. Founded by Igino Cafiero WG17 and Aubrey Donnellan in 2017, Bear Flag Robotics is developing cutting-edge technology that promises to give farmers remote control over their agricultural equipment.

The startup isn’t seeking to reinvent the wheel; instead, it’s retrofitting existing tractors with its sensors and actuators. Bear Flag wasn’t always meant to be a farming venture: Cafiero started building the company’s first prototype as a mining solution for an uncle-in-law’s rock quarry but shifted his focus when orchard owners in California expressed interest. Bear Flag’s work is paying off—the startup has raised at least $4.5 million to date.

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