Ian Vaughn recently joined our Corps of Exploration as a mapping specialist for our two-week expedition in the submerged Anaximander Mountains off the coast of Turkey. He’s currently a PhD student at the University of Rhode Island studying methods for high-resolution mapping from robotic vehicles, so I asked him to tell me a little bit more about his work aboard the ship.
Can you tell me about what your role on Nautilus is as part of the Corps of Exploration?
Ian: I'm here as a mapping specialist. In addition to assisting the pilots and science team during mapping operations, mapping specialists also help maintain the relevant sensors on ROV Hercules and conduct the initial processing on mapping data to make sure it was captured correctly. On this leg, I'm here to map the interesting geology of the submerged Anaximander Mountains and to produce maps that provide context for both biological and geological samples.
How do you go about generating these detailed maps of the seafloor?
Ian: The mapping process starts by running survey lines with Hercules, back and forth over the seafloor. While that's the most visible part of the process to everybody on the website, it’s only the beginning for us. Once Hercules is recovered, we gather data from our sensors and Hercules' navigation suite and do an initial reconstruction while still on the ship. This map is usually pretty rough, but it helps the scientists understand what they saw and makes sure that the sensors are all working. Once we get back to the lab, it takes months to clean up the data and run it through sophisticated computer algorithms to further improve the results. These final maps are what usually get published.
What different types of mapping did you do on this leg?
Ian: Right now, we do three basic types of mapping. The first is stereo imaging, which uses two cameras on the back of Hercules and a powerful strobe to take two images of the seafloor at exactly the same time. From these two images, we can extract depth information and build a full textured, 3D model. We also have a multibeam sonar that measures the distance to the seafloor with a series of beams – it’s kind of like 500 depth sounders arranged in a fan. We've also started working with this really interesting laser sensor that uses a green laser and a third camera to measure the seafloor very precisely. My colleague Clara Smart can tell you more about that when she gets on board Nautilus.
Can you tell me about this map we made this season?
Ian: This is a small multibeam map the summit of the Kula mud volcano. The center of the survey shows where the mud bubbled up from below, and the waves radiating out from that are mounds carved out as mud flowed down the sides of the volcano. The map size is about 30 x 30 meters, or about 8000 square feet. The HD camera on Hercules gives great detail, but to paraphrase Dr. Ballard, it's still like trying to understand a football field while looking through a drinking straw. So, these maps are invaluable to understanding what we’re looking at.
Very cool! How did you get into mapping the seafloor?
Ian: I'm not really sure. In college, I had a lot of fun working on a student-lead project to build an Autonomous Underwater Vehicle to participate in an international student competition. That experience piqued my interest in underwater robotics and, eventually, led to enrolling in graduate school at the University of Rhode Island. You never know where you’re going to end up when you follow what interests you!
What kind of background do you need be a Mapping Specialist aboard Nautilus?
Ian: The current mapping specialists come from a diverse background, including Geography, Engineering, and, in my case, Computer Science. Everything is heavily dependent on computers, so a solid background in programming is helpful. The algorithms that stitch everything together are complicated, and understanding them requires a solid understanding of mathematics. Finally, knowledge of cameras can be very helpful. Some of our mappers were avid photographers long before joining the Nautilus.
On a personal note, what’s your favorite part about sailing with Nautilus?
Ian: The people! Nautilus is full of people from all over the world, and as clichéd as it may sound, every one of them has a story to tell. It's also a very diverse group, both personally and professionally – just read everybody's bio on the website!