This week, a surgical robot, designed by UW researchers to perform medical procedures in extreme environments, will dive 400 feet below sea level to undergo testing at Aquarius, NASA's undersea habitat.

The robot, also known as Raven, was created to provide care to patients in situations where it may not be practical — or possible — to have a surgeon present. Battlefields, natural-disaster sites, space stations and remote regions of the world are a few places Raven could potentially impact patient care.

A surgeon is able operate the lightweight and maneuverable robot from any location with exact precision.

"Raven can replicate anything surgeons can do," said Dr. Andrew Wright, assistant professor of surgery and researcher on the project.

Raven's potential value on the battlefield was recognized immediately by the Army which has invested the initial $2.5 million dollars that has funded the project thus far.

"Iraq has shown the need to reduce personnel, including medical, in the field," said Jacob Rosen, research associate professor of electrical engineering.

By operating Raven from an armored vehicle, the military can have mobile medical attention with a higher level of specialization and a lower human-risk factor.

Using a type of three-dimensional joystick, a surgeon moves his or her hands to guide Raven's movements. The doctors use their hands as they normally would in an operating room, Wright said. Those signals are then transmitted via the Internet to the robot.

During the upcoming tests, the signal will be sent along standard commercial Internet lines to Key Largo, Fla. From there, it will switch to a wireless connection to arrive at a buoy that is connected with a cable to the Aquarius undersea station.

"Raven can be deployed anywhere that can receive an Internet signal," Rosen said.

This weeks' tests are part of NASA's 12th Extreme Environment Missions Operations and are designed to evaluate Raven's performance under environmental pressures. The underwater station is subject to a level of pressure that can cause mechanical failures.

Blake Hannaford, electrical engineering professor, director of the BioRobotics Laboratory at the UW and one of the key developers of Raven, said he hopes the tests will show if the robot's most delicate parts can survive the rigors of transport and high pressure. If this is the case, Raven will carry out a standardized task known as "fundamentals of laparoscopic surgery," which uses plastic cubes and pegs to rate the quality of surgery, he added.

Wright, along with Dr. Thomas Lendvay of the Seattle Children's Hospital, will be controlling Raven during the tests.

While the upcoming tests are the most advanced to date, it will not be the first time Raven has been deployed. Last summer, the robot was tested in Simi Valley, Calif., using an unmanned aircraft to transmit the wireless signal. The signal was beamed from the ground and then bounced back down to the surgical machine.

Though the researchers said testing has gone well, reliance on existing networks means Internet traffic dictates delay between the surgeons and Raven. Rosen said procedures can be carried out with up to one second of delay; however, fluctuations in the delay time can cause problems.

"A slower fixed delay is better than a fast one that frequently changes," he said.

When a surgeon is on site, delay is not an issue, and preliminary tests on animals have yielded excellent results, the researchers said.

Robots are currently being used in operating rooms, but are larger and more cumbersome than Raven, who will weigh almost 2,000 pounds less than those presently employed, Rosen said.

Raven now operates with two arms, but will soon be modified to use four, doing the work of two surgeons at once.

"In the future, robots will be able to perform surgery better than humans can," Wright said. "They are capable of a much higher degree of precision than we are."

Reach contributing writer Jeremiah Rygus at news@thedaily.washington.edu.