What is a Robot?

Say the word "robot" and many of us will conjure up an image of the red camera lens of the malevolent HAL from the classic film 2001: A Space Odyssey or the Model B-9 Environmental-Control Robot, better known just as Robot — the "bubble-headed booby" that Dr. Zachary Smith could not get to do his malicious deeds on the 1960s television series Lost in Space. Then there are the more modern machines, such as the Terminator, Battlestar Galactica's cylons, and of course the robots from Star Wars.

The term does have its roots in entertainment, but it originated much earlier than many people think. The word robot made its debut in 1921, in the play R.U.R. (Rossum's Universal Robots) by Karel Capek. It comes from the word "robota", a Czech term for forced labour.

Since then, fictional robots have often been portrayed as machines that are in competition with humans, attempting to break away from their roles as servers of people to assert their independence and freedom to act and think as beings in their own right.

The noted science fiction writer Isaac Asimov didn't see them that way. In his stories, robots served humans. He penned Three Laws of Robotics, later adding a "zeroth law." They were:

• Law Zero: A robot may not injure humanity, or, through inaction, allow humanity to come to harm.
• Law One: A robot may not injure a human being, or, through inaction, allow a human being to come to harm, unless this would violate a higher order law.
• Law Two: A robot must obey orders given it by human beings, except where such orders would conflict with a higher order law.
• Law Three: A robot must protect its own existence as long as such protection does not conflict with a higher order law.

The Oxford English Dictionary defines a robot as:

• One of the mechanical men and women in Capek's play; hence, a machine (sometimes resembling a human being in appearance) designed to function in place of a living agent, esp. one which carries out a variety of tasks automatically or with a minimum of external impulse.
• A person whose work or activities are entirely mechanical; an automaton.

The International Organization for Standardization also has a definition. Under ISO 8373, a robot is: "An automatically controlled, reprogrammable, multi-purpose manipulator programmable in three or more axes, which may be either fixed in place or mobile for use in industrial automation applications."

Your microwave oven fits that bill, even though many wouldn't think of it as a robot.

We put the question to several experts in robotics. Each of them had a slightly different take on the issue of what a robot actually is.

Alan Mackworth, the director of the University of British Columbia Laboratory for Computational Intelligence and president of the American Association for Artificial Intelligence, says robots are goal-oriented.

"It's a machine that can sense and act and react in the world and possibly involves some reasoning for performing these actions, and it does so autonomously. By that definition a thermostat would be a robot. Though it's not 'aware' it has a goal, that awareness isn't required."

Rodney Brooks, the director of the Massachusetts Institute of Technology computer science and artificial intelligence laboratory, thinks current notions of "robot" are too broad.

"To me a robot is something that has some physical effect on the world, but it does it based on how it senses the world and how the world changes around it. You might say that a dishwasher is a robotic system for cleaning dishes but to me it's not really. First it doesn't have any action outside the confines of its body. Secondly, it doesn't know about the dishes inside it. It just spurts hot water around and swishes it and whether there are dishes there or not doesn't affect its behaviour, so it's not really situated in the world, it's not understanding the world around it in any sort of meaningful way.

Gregory Dudek, the director of the Centre for Intelligent Machines at McGill University in Montreal, sets three criteria for robots.

"They have to have a way of making measurements of the world, they have to have a way of making decisions — in other words, something like a computer, you could call that thinking informally — and they have to have a way taking actions. And so if a thing has all three parts, we might call it a robot."

Joseph Engelberger has been called the father of robotics. The American engineer and entrepreneur helped create the first industrial robot. In 1966, he appeared on The Tonight Show with Johnny Carson along with a robot that served a beer, sunk a putt and led the band. Asked to define a robot, he once said, "I can't define a robot, but I know one when I see one."