When they married nearly two decades ago, Hans Moravec promised his wife that one day he'd get her a robot to vacuum the house.
He's expecting to deliver on that promise one day soon.
Moravec, a professor at Pittsburgh's Carnegie Mellon University, says the pace of progress in robotics research labs suggests that household robots might become commercially available in five to 10 years.
"Robots have started doing things all over the place," said Moravec, author of the book, "Robot: Mere Machine to Transcendent Mind."
"The performance is just astronomically above what it was in the '70s and '80s, when we could barely make a computer cross a room," he said.
Although most consumer-oriented robots are still being refined in the labs, a few have begun making their way into the marketplace, showing the tantalizing potential of self-guided machines.
One is AIBO, a robot pet manufactured by Sony Corp. The dog-like device can walk on all fours, wag its tail, sit, beg and even dance. About 2,000 of the devices sold out instantly when they were offered at $2,500 each.
Another is AutoMower, a battery-driven lawn mower that will trim your grass, untouched by human hands.
The AutoMower uses sensing technology to stay on your property and to avoid obstacles like trees, flower gardens and even the family dog. When its battery runs down, AutoMower finds its docking station and recharges itself.
The maker, Husqvarna, expects to introduce the mower to the U.S. market early next year at a price of $1,500 to $1,800.
"I think everyone today is looking for technology to help simplify their lives," Husqvarna spokeswoman Barbara Paez said. "This is just another way that technology can help take away one of the household chores."
That, at least, is the hope that's driving robotics experts to take their creations to a new level of performance.
Robots of a sort have already been working for some time in industrial settings. Often, they're single-function devices that simply pick up a piece of material to move it.
But such robots are so limited in capability and function that many don't even consider them worthy of being called robots.
In order to function in the "real world" -- that is, in the changing environments of home and office -- robots have to be smarter than remote-controlled machinery.
For most of the past two decades, that hurdle seemed insurmountable. The technical challenges of designing a robot that could see and respond to its environment were overwhelming.
Part of the problem was the complexity of the task. Humans do extraordinarily well at navigating the world and reacting to it. By contrast, even a sophisticated robot seemed as stupid as a stone.
In recent years, though, advances in the power of computer chips have enabled robotics researchers to build machines that are capable of thinking on their feet, so to speak.
By one estimate, today's top personal computer chips have the capacity to process information on a par with the brain of an insect or goldfish.
As a result, the latest experimental robots can quickly identify obstacles and calculate a way around them. They can map entire rooms and then scan them again later to determine if anything has moved or if something new has been introduced. It's difficult to underestimate the significance of this progress in getting robots to see and react in real time.
Quite simply, none of the tasks that humans would most like robots to perform -- from cleaning bathrooms to taking out the trash -- would be possible without that skill.
Moravec said progress in robotics will put robots into common use within the next decade or so.
The first wave, he said, will be a new generation of industrial robots that move more easily through warehouses, office buildings and the like. They will be followed by a second wave of single-purpose consumer robots for vacuuming and mowing. In a third generation, the home robots would have a movable arm that could pick up things, carry things and even wash things.
"Each round of these robots reveals more things that you could almost do with them if only they had a little bit better software and more hardware," Moravec said.
Joseph Engelberger, chairman of HelpMate Robotics in Danbury, Conn., says a multifunction home robot is a natural assistant for the aging population. "It would be a companion for an elderly or infirm person so they don't have to go to the nursing home," Engelberger said.
"It's a creature that would know the house, cook and clean, help you get out of bed, help you eat, monitor home security, measure vital signs. That's no $2,500 dog."
HelpMate, which already has more than 70 robots operating in hospitals throughout the United States, is seeking to raise $5 million for the development of such a household robot.
The final product might be expensive. (At $50,000, Engelberger compares it to the cost of a luxury car.) But that same robot might lease for $600 or $700 a month -- just a fraction of the cost of nursing-home care, or even of a daily visiting nurse.
"The economics are very powerful," Engelberger said.