A surgical robot goes underwater in Florida
Photo: David Clugston for IEEE Spectrum
Last year, Blake Hannaford and Jacob Rosen of the University of Washingtonâ''s BioRobotics Lab wrote an article for Spectrum about their surgical robot, Raven, and a field test in the California rangelands, where a surgeon commanded the robot remotely.
Early this year, Raven headed out to another extreme environment: the Aquarius underwater habitat off Key Largo, Florida. In the experiment, part of NASA's Extreme Environment Mission Operations (NEEMO) project, surgeons teleoperated the two-armed robot all the way from Seattle.
Automaton spoke with Hannaford to get the details.
Automaton: First of all, last time we talked your group was having a hard time finding a name for the robot. Now it's called Raven. Is that because of its lustrous black looks?
Hannaford: Yes. We finally were able to name it when we let go of the idea that it had to be an acronym.
Automaton: Yeah, acronyms are awful, but my employer is the IEEE, so let's move on... In the California field test last year, you crammed the robot and its control system into two cargo vans and drove 2000 kilometers from Seattle to Simi Valley. This time, how did you get the robot to Florida?
Automaton: And how did Raven behave at the undersea lab? What kind of manipulation tasks did you try?
Hannaford: Mitch Lum of our lab supervised operations of the robot from the shore station. The robot was assembled and started up by surgeon Tim Broderick and NASA astronaut flight surgeon Joe Schmidt. The remote surgeons controlled the robot to perform a task called the "Fundamentals of Laparoscopic Surgery" (FLS), which is a benchmark being developed for scoring surgical skill.
Automaton: Very cool. Please keep us posted about the scores -- did the astronaut win? One final question: where's Raven going next?
Hannaford: We are working on three new remote projects.
Automaton: Can you elaborate?
Hannford: Um. Stay tuned.
For more details -- and tons of photos -- on Raven's Florida trip, visit the BioRobotics Lab's NEEMO 12 page.
UPDATE: Some folks didn't believe the FedEx story, but it's true: the researchers packed the robot into crates and FedEx'ed them to Florida. Other folks asked about another leg of the trip: the one from the shore station to the Aquarius lab. Here's an explanation from project manager Mitch Lum, who supervised the divers and also got to go down to the underwater habitat to fix a balky cable:
The process for taking equipment down to the undersea habitat is called "potting" and is performed by divers from NURC (National Undersea Research Center), NOAA, and the Navy. Potting typically involves putting equipment in sealed cylindrical steel vessels (pots). Most items can go down in the pots, but the RAVEN manipulator arms were larger than could fit, so each arm was placed in a foam shell made in the lab, then into a sealed dive bag made by Divers Unlimited International (DUI).
An unforeseen problem with our foam shells was that it collapsed under the pressure of being 50 feet underwater. Moreover, the foam was incredibly buoyant making it difficult for the divers to take it down (if I recall correctly, it took 400 pounds of ballast to get the dive bag down). Due to the collapse of the foam shell at depth a cable was damaged. The divers felt that surfacing the robot arm to repair it on the boat or back on land would be hopeless as it would likely get damaged again going back down. The only way to make the mission happen was for someone to dive into the habitat and fix the broken cable.
Jim Buckley and James Talacek both took their one day off before the mission to escort myself and Diana Friedman out to Aquarius for the repair. We did a lot of pre-planning before the dive, because the maximum no-depression dive time for that depth is 90 minutes. On Saturday we did one dive so I could evaluate what was damaged and what we would need to fix it. On Sunday, there were more divers potting equipment down, so that's when I was able to repair the cable. Total dive time of 83 minutes of the allowed 90.