As NASA sets its sites on manned missions back to the moon and as far away as Mars, the space agency is participating a series of tests this week to determine if robotic technology is the key to providing adequate medical care for its astronauts during such extended spaceflights. On board a military C-9 aircraft flying in parabolic arcs over the Gulf of Mexico, four surgeons and four astronauts are performing simulated surgery by hand and using a robotic device developed by SRI International to determine if the robot's software can compensate for errors in movement that can occur during turbulence and under varying gravitational conditions.
The test flights last as long as three hours and soar up to 32,000 feet (9,755 meters) or dip as low as 24,000 feet (7,315 meters). The plane's nose is kept at a 45-degree angle during ascent and descent, simulating a microgravity environment by creating short periods of weightlessness alternating with stronger gravity during which time the surgeons practice making incisions and suturing them shut by hand as well as by using SRI's M7 robot on a special six-inch (38.7-centimeter) square of multilayer material designed to resemble human skin. They also attempt to cut through the "skin" to the fascia—a fibrous network of tissue between the skin and underlying muscle and bone—and then stitch up their incisions.
After the test flights wrap up on Friday, NASA, SRI and researchers at the University of Cincinnati will study the synthetic skin models and review video of the test runs.
The M7's robotic arms each weigh about 10 pounds (4.5 kilograms) and are about the same size as a human arm. The device is bolted to the aircraft's cabin, sits about 2.5 feet (0.76 meter) off the floor and is powered by the same system used to power the aircraft. It can be operated by a single physician, who views the procedure through a camera mounted between the arms and uses a remote control to manipulate them. "As the surgeon moves the controller, the robot follows," says Thomas Low, director of SRI's medical devices and robotics program. "If there's an accidental movement, the robot will compensate."
The M7 debuted in 1997 as a device for testing how robotic equipment could assist with the care of soldiers on a battlefield, Low says. This latest round of experiments includes software designed to allow the M7's robotic arms to compensate for sudden and severe changes in movement. "The robots are not just mimicking the surgeons' movements of their hands," Low says. "We have created an algorithm to adjust for accidental movements that the surgeon might make as a result of the change in their environment, such as a change in the movement of the plane."
The C-9 on Tuesday flew 60 parabolas in an effort to determine the impact of movement and gravity variations on the M7 and the surgeons. "This is essentially to get enough zero-gravity time for the experiment to be relevant," says Low, an amateur pilot who flew on the C-9 during the tests. "Our goal is to show that a robot can do procedures in a rough environment where a surgeon could not. The hypergravity is more difficult to deal with. If you move your head quickly, it's very easy to get nauseous."
Although there is no requirement that a physician be part of a spaceflight crew, at least two crew members are given medical training before each mission, NASA flight surgeon Josef Schmid says. This training is meant more to identify and treat common space- and pressure-adaptation problems that the astronauts may experience than to treat serious medical conditions. Medical experts like Schmid on the ground serve the astronauts' health needs before and after each mission.
Once the astronauts blast off, however, physicians are limited in the care they can provide. "Our surgical hands today are the crew members' hands," Schmid says. No remote surgical capabilities exist to bridge the distance between earthbound medical support and the astronauts, which is why Schmid envisions a time when physicians will be part of every crew sent into space, especially during missions to the moon or to Mars that may last months or even years.
The tests were taking place as NASA Administrator Michael Griffin this week told the 58th annual International Astronautical Congress in Hyderabad, India, that he is convinced the first humans will land on Mars by 2037. Griffin's comments also coincide with the 50th anniversary of the Soviet Union's historic launch of Sputnik 1 into space. During his tenure as NASA chief, Griffin has become a controversial figure for, among other things, questioning whether global warming is an issue that needs to be imminently addressed and for claiming two years ago that it was a mistake for NASA to continue the space shuttle program rather than to prepare for trips to the moon and beyond.
The technology NASA and SRI are testing is still in its infancy as the researchers attempt to answer basic questions such as whether a robot can tie a knot for a suture or place an intravenous needle under conditions simulating spaceflight. "That's the whole thing, to really be able to push the technology," says Schmid, who was part of an 12-day NASA Extreme Environment Mission Operations (NEEMO 12) mission earlier this year during which a six-member crew tested the M7's ability to conduct a variety of advanced medical technology experiments, including robotic telesurgery, in a laboratory located more than 60 feet below the ocean's surface in the Florida Keys National Marine Sanctuary. The NEEMO project is a direct extension of the space program as it explores the inner space of the ocean, trains astronaut crews for long-duration missions and serves as a platform for scientific discovery and equipment evaluation for long-term spaceflight.
Although voyages deeper into space are still several years away, the M7's success during the trials means the technology could be used more immediately to perform lifesaving surgery in the back of a speeding ambulance or in the cabin of a military aircraft used to evacuate and treat wounded soldiers.