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Dramatic advance enables remote control of robots via Internet

Dramatic advance enables remote control of robots via Internet

Over the past five years, the Internet has grown to become the most recognizable lane on the Information Superhighway. Now engineers at Washington University have blazed a new trail that makes the Internet the Action Superhighway.

T.J. Tarn, Ph.D., professor of systems science and mathematics in the School of Engineering and Applied Science, and doctoral student Kevin Brady are the first persons to control a robot live via the Internet. In the first live demonstration of the new technology last spring, they dazzled engineers at the Flagship Conference of the Institute of Electrical and Electronics Engineers (IEEE) Robotics and Automation Society when Brady pulled a joystick in Albuquerque, N.M., and controlled the motions of a Puma robot in Tarn's University laboratory more than 1,000 miles away. Standing on a stage, Brady worked in tandem with the robot in front of the audience, who watched the robot on a video monitor.

Tarn presented a paper explaining the technical aspects of his accomplishment at the International Federation of Automatic Control Symposium on Robot Control this fall in Nantes, France.

The three-minute experiment at the IEEE conference was a difficult task for a robot: It involved avoiding a box in its path to perform a manufacturing task -- picking up an object and placing it somewhere else. While picking up and moving an object is routine robotic work, avoiding the box and taking commands from a remote operator in real time over a crowded public network was extraordinary. The "teleoperations" feat was a major step for the burgeoning field of robotics and a giant leap for telecommunications, adding a previously unexplored dimension to the Internet -- remote control -- and providing new horizons for other applications.

"This was no virtual reality experiment, but a live performance that shows a novel approach to the Internet and other remote communications systems," said Tarn, who directs the University's Center for Robotics and Automation. "In accomplishing this, we've shown that the Internet can be a medium to transfer force, rather than strictly a communications system, which is the way it's always been seen."

Raymond W. Harrigan, Ph.D., manager of the Intelligent Systems and Robotics Center at Sandia National Laboratory, Albuquerque, N. M. said: "This is very cutting-edge technology in an uncertain environment. If the Net goes down, or you lose a connection or send a wrong command, everything falls apart. People have done demonstrations using the Net before. But now we are using it to perform experiments in real time where all of the conditions are not highly controlled, and this was an exciting success. The accomplishment represents a mindshift in usage of the Internet."

The breakthrough presents opportunities that even R2D2 never had. Tarn envisions long-distance learning and research opportunities where engineers and scientists, linked to a national laboratory, could experiment electronically with robots and other areas of service and manufacturing, or secondary school students could perform hands-on science and engineering experiments. People from divergent points then could share resources and save expenses.

Even more intriguing, physicians or technicians could perform robotic medical procedures from afar, and rescue squads could direct robots to clean up hazardous materials spills without risking human health.

If these scenarios sound fantastic, consider: Robots already spot weld and paint in U.S. and Japanese automobile factories; sheer sheep and feed cattle in Australia; and trim trees in vast, sparsely settled regions of Canada. They are used in oceanic and space-based research and in medicine. Endoscopy and some aspects of artificial hip replacement surgery -- requiring a super-human steady hand -- rely on robotics.

The work of his graduate student Kevin Brady, a doctoral candidate in systems science and mathematics, helped Tarn address the problem areas of time-delay control and intelligent supervisory capability to accomplish his teleoperations feat. He used sophisticated algorithms -- mathematical programs that make the decisions for a machine to operate -- that took into consideration the several-second lapse through cyberspace between Albuquerque and St. Louis to avoid any lag between command and performance.

"One of T.J.'s specialties is command in a delay situation, a major problem in controlling robots in space and under water," noted Harrigan. "What can happen is you get a delay that is similar to a poorly dubbed foreign movie, where the actor's lips and voice aren't in sync. But he handled that very smoothly."

Tarn's concepts already have been integrated into a huge robot working at Oak Ridge National Laboratory in Tennessee to remove nuclear wastes.

"Remote control of robotic motion has long been recognized as fundamental for a variety of important applications, for example, remote remediation of harzardous waste and/or radioactive material," said Christopher I. Byrnes, Ph.D., Chair of the School of Engineering and Applied Science. "Two things are remarkable about Professor Tarn's advance. Firstly, while remote control has been demonstrated using dedicated communication lines, this feat was done on-line over the Internet, which is very far from being a dedicated communications line. The second aspect is Professor Tarn's ability to convert sophisticated advances in non-linear dynamics and control into robust and reliable algorithms for controlling robotic motion."

-- Tony Fitzpatrick

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