Startup Blue River Technology — the brains behind a weed-pulling, machine-learning lettuce robot — have raised another round of $10 million to hire new scientists and engineers and develop new robotic products for agriculture. Data Collective Venture Capital led the round, which also included Eric Schmidt’s Innovation Endeavors, and Khosla Ventures.

The company’s lettuce bot rolls slowly (1 mile per hour) down a row of lettuce plants, with a camera pointed at the ground. One set of algorithms determines whether or not the robot is seeing a plant, another set of algorithms determines if the plant is a weed or not (to about 98 or 99 percent accuracy) and a third set of algorithms determines when the correct moment is to inject the deadly dose of fertilizer on the weed.

The computer determines that these plants are lettuce.

The idea is that the lettuce bot can remove weeds without human labor…