The robot butler has a long and frequently chequered history. From Robbie the Robot in Forbidden Planet (who could bring a nicely shaken martini) through to HAL 9000 in 2001: A Space Odyssey (which served food via a hatch, then later killed you), the idea that there must be a better method of getting refreshments handed out than making a person push a trolley is one that just won't go away.

So in the search of that most elusive of robotic holy grails, Paul Rybski and his team at Carnegie Mellon University in Pittsburgh have spent two years and $20,000 to build a "snackbot" with laser navigation, sonar sensors and a Point Grey Bumblebee 2 stereo camera (that's its eyes).

And what does it do? Delivers snacks. True, its first task in front of a watching New York Times reporter – delivering a granola bar – would hardly tax the average three-year-old. "Hello, I'm the Snackbot," it said as it headed over. "I've come to deliver snacks to Ian. Is Ian here?"

The Snackbot is only one of dozens of robots that are emerging to make food. You can get a cooking robot from Fanxing Science and Technology, in Shenzhen, China; it can fry, bake, boil and steam Chinese delicacies. Not to be outdone, scientists at the Learning Algorithms and Systems Laboratory in Lausanne, Switzerland, built the Chief Cook Robot. Its speciality: omelettes.

Why? Because omelettes seem like a nice, non-threatening sort of meal. In fact, the whole idea of robot chefs (and snackbots) is to get us used to the idea that they're just nice servants which, once costs fall far enough, will be all around us.

Perhaps. Then again, it's Japan that's leading the way in robot food preparation, with the Famen restaurant in Nagoya using two robots able to cook up to 800 bowls of ramen (noodles) daily. The problem is that they do cost about £80,000 each. And when there aren't enough customers, they indulge in a pre-programmed knife fight. Remember HAL? Then keep clear of the ramen robots.