Oblivious to the punishing midday heat, a wheeled robot powered by the sun and infused with artificial intelligence carefully combs a cotton field in California, plucking out weeds.

As farms across the United States face a shortage of laborers and weeds grow resistant to herbicides, startup Aigen says its robotic solution — named Element — can save farmers money, help the environment and keep harmful chemicals out of food.

"I really believe this is the biggest thing we can do to improve human health," co-founder and chief technology officer Richard Wurden said as robots made their way through crops at Bowles Farm in the town of Los Banos.