Heindel & Sons, one of seven farms in the country that are experimenting with robotic milking systems, has trained most of its cows to walk up to a milking station and spend a few minutes there munching grain while the robot’s quietly moving parts prod at the animal’s udder.

A laser locates the cow’s nipples, which are cleaned by rollers coated with disinfectant before being milked by long, white suction tubes on the unit’s “milking claw.” Vacuum-activated rubber rings at the end of each tube massage the nipple, prompting the cow to release its milk.