Mobile Robots Bring Electronic Touch To Living, Working

THE mobile robots are coming. Their advance is so slow that it isn't setting off alarm bells. Nevertheless, here and there, mobile, intelligent machines are making breakthroughs in the lab and even occasionally in the marketplace.

"One of the fantasies was that we would use robots in our homes to clean our rooms and mow our lawns," says Takeo Kanade, director of the Robotics Institute at Carnegie Mellon University here in Pittsburgh. The fantasy hasn't happened yet, he adds, but "there are interesting signs."

For example:

*Dr. Kanade's institute built a robot minivan that drove itself from Pittsburgh to San Diego last month at an average speed of 63.8 miles per hour. A real driver was behind the wheel to intervene just in case. But the vehicle, called the Navlab 5, guided itself 98 percent of the way.

*A Pittsburgh company, Denning Branch International Robotics, is negotiating to buy a large manufacturer of automated guided vehicles or AGVs. AGVs are old technology. They have been carrying parts in factory floors for two decades. By putting in its advanced sensing and mobile technologies, Denning hopes to create much "smarter" machines.

*At least one mobile robot has made it to the consumer market. For around $2,000, homeowners can buy the MOBOT, a solar-powered grass-cutter that mows up to a quarter-acre of lawn without human intervention. Its maker, Poulan Weed Eater in Shreveport, La., sold 200 MOBOTs last year and 500 this year.

These robots are a far cry from the robot welders and painters that auto companies and other manufacturers have used for years. For one thing, the new machines move themselves around. For another, they have the ability to sense their location.

A typical AGV uses a path laid down on the factory floor to guide it. If something blocks its way or gets it untracked, the machine can stop but little else. Mobile robots, by contrast, are able to figure out where they are, where they should be, and find a way to get around the obstacle and back on track.

Mobile robots are starting to enter the marketplace because their technology is improving while their costs are falling dramatically.

When Carnegie Mellon built its first self-driving Navlab in 1986, it took a supercomputer and three to four other high-powered computer workstations to get the vehicle to move at a top speed of five miles per hour. Total cost: about $1 million.

The university's latest Navlab uses one laptop workstation computer to guide itself at highway speeds. Total cost: $30,000.

Not just the cost of computer power has come down. Building a sophisticated, highly flexible robot cost $1 million in 1980, says Takeo Oomichi, assistant chief engineer in Mitsubishi's Takasago Research and Development Center in Japan. A decade later, it cost one-tenth that amount. By 2000, he predicts the price will come down to $10,000. "I look for the day where it will be as easy to buy a robot for a new application as buying a car," he says.

The immediate market for mobile robots is for use in highly dangerous or inaccessible places. Mitsubishi, for example, is working on a wall-climbing robot that uses ultrasound to inspect the welded seams on the inside of nuclear-reactor vessels. Another Mitsubishi research project is to build a robot that changes its shape. That way, a small machine could move through small pipes, Dr. Oomichi says. When it reached a valve, the robot could reform itself to be able to move through the open space.

Kanade looks for specialized robots to be used in hazardous-waste-handling and cleanup as well as mining. "Those are areas where I think you will see real robotics pretty soon," he says.

Denning Branch is hoping to make its mark with less expensive, general-purpose mobile robots. The company is working on a stair-climbing wheelchair robot, a robot suitcase, and a $5,500 educational robot that looks like a three-wheeled canister vacuum cleaner.

One of its existing products is RoboScrub, a machine that cleans floors. In four years of marketing, the company has sold 31 machines, including one that NASA uses to help clean the space shuttle. Allan Branch, the company's president, says he hopes for more sales as the machine's price comes down. Initially priced at $69,000, the RoboScrub is about to be released in a second generation, selling for $29,000.

"The robotics industry is in a cycle," Mr. Branch says. "It might be 100 years [long], and we're in the second decade."