The Smart Pigs Beneath Our Feet
By Mark Frauenfelder, Wed Sep 01 08:15:00 GMT 2004

Wireless pipeline robots are the first in a race of remote control droids that will do our dirty work.


Listen carefully -- can you hear the smart pigs beneath your feet? If so, do not be afraid. They aren't genetically engineered subterranean hog-things -- they're two-ton robots designed to inspect the pipes that supply natural gas to our homes and factories. Pushed along by gas pressure, these "smart pigs" -- so named because of the squealing sound they make -- check pipes for trouble by recording magnetic flux signals, which can indicate leaks or weak spots.

In the U.S. alone, gas pipe inspection and repair costs $300 million a year, and costs are sure to go up as gas consumption increases. Recent pipeline ruptures in the country's decades-old pipe infrastructure has prompted Congress to pass a Pipeline Safety Improvement Act, which requires every pipeline in the country to be inspected in the next decade, with re-inspections occurring every seven years after that.

The Unpiggable Pipeline

The problem is, many sections of the pipeline network are "unpiggable" because of sharp turns in the lines, changes in diameter, low pressure or because the pipes are too weak to bear a hefty pig's load. And because the pigs must tethered to a cable that supplies power and provides communications and control signals to a remote operator, their range is limited to about 500 feet of straight pipe, raising costs since a new insertion point must be excavated every 500 feet or so.

But there's a new pig in town, and this one's off the leash. Dubbed the Explorer, this untethered, wireless robot consists of segmented cylinders equipped with arms that grip the inside of the pipe to propel it forward. Because it's made of segments (resembling linked sausages), the Explorer can go where no smart pig has gone before: around 90-degree bends in pipe tees and elbows. And because it's wireless (using Wi-Fi, though it could be modified to work with other types of radio communication) and has a range of thousands of feet, excavation costs are dramatically reduced.

The Wireless Smart Pig Goes to Yonkers

Explorer was invented by Hagen Schempf, a Carnegie Mellon University robotics researcher, in collaboration with the Northeast Gas Association, the National Energy Technology Laboratory of the U.S. Department of Energy and NASA. In August, the remote-controlled robot completed a successful mission in Yonkers, New York, where it crawled through an 8-inch diameter cast-iron gas main that had been laid in 1890. Explorer transmitted real-time images taken from its fisheye lens video camera via Wi-Fi to a remote operator stationed in a van parked in the street.

According to a spokesman for Con Edison, the Yonkers test was the first time an untethered robot inspected a live gas main. He believes the Explorer will significantly reduce gas main inspection costs.

Schempf is convinced that the Explorer represents the "tip of the iceberg." He envisions a wide variety of wireless robots designed to carry out dangerous or costly tasks normally assigned to humans: preventative maintenance, systems inspection and emergency response. Schempf should know -- he heads the Hazardous Environments Robotics Laboratory at the National Robotics Engineering Consortium, and has invented robots that remove toxic substances from underground tanks and asbestos from old buildings. He's also the inventor of a robot called the Dragon Runner, a reconnaissance and fighting robot for the US Marine Corps. Designed to peek around corners and act as a sentry, Dragon Runner is controlled by a remote human operator who can send the robot into situations too risky to send a soldier.

Explorer and Dragon Runner are two examples of an emerging science called telepresence -- equipping a wireless, mobile robot with various sensors and effectors to give a human operator the ability to see, hear and "smell" things from a remote location. It's useful in dangerous situations (such as war zones, and toxic or hazardous environments) or inaccessible areas (such as an 8-inch diameter pipe).

Televactions with Telepresence

Looking further out, telepresence robots could be used for things like virtual vacations. Imagining being in your house in Mexico City or Tel Aviv, controlling a wireless robot rolling through the galleries of the Louvre in Paris. You could direct the robot to follow along with a group led by a tour guide, aim its high-resolution video camera on different works of art, and listen to the guide explain their significance. Then, you could roll your robot down the Champs Elysees and into various boutiques, perhaps picking up a few souvenirs (and storing them in the robot's "glove compartment.")

Afterwards, you might want to send your robot to a sidewalk cafe and order an espresso. As the robot "drinks" the coffee, you could attach a taste bud stimulator to your tongue that would receive the signals picked up by the robot's flavor and aroma sensors. Finally, you could direct the robot into the middle of the street, order it to lift up a manhole cover, and say to the army of smart pigs toiling in the underground network of gas pipes and sewers, "Thanks for making all this possible!"