Cambridge researchers have a new lettuce-picking robot. Its success underlines the challenges of automating vegetable picking. (Credit: leungchopan/shutterstock)

A skilled human can pick a head of lettuce every 10 seconds. Just reach down, slice a mature head off its stalk, bag it, toss it in the cart. Easy, right?

Tell that to wannabe veggie-picking robots. For them, it’s actually quite a challenge.

Earlier this week, a team from the University of Cambridge published their latest rob