Now that Boot Camp is over and class is back in session, I really miss the "science camp" feel of our weeklong AUV event. It was a great experience that allowed me to learn a lot about the practical applications of our vehicle. After surviving the first half of Boot Camp, I felt pretty ready to take on the second. On the fourth day, Justin, Adam, Chooks (CCOM graduate student) and Meme (NOAA OE) headed out on the boat for a full day of surveying. Earlier that week, all of the Boot Camp participants were split into two teams to independently create two separate campaigns of the same area. Once the data returns to shore, it will be divided up between everybody and tackled so that we can observe the differences between the two and determine if one was more accurate or efficient than the other.
On day five, Trevor and Carter left in the morning to execute a mission they had designed the previous evening. The mission would have some engineering lines as well as lines surveying a nearby shipwreck, the Empire Knight. The Empire Knight was a U.S. Liberty Ship that ran aground during a storm in 1944 and rests now near Boon Island, Maine.
While they were out and about, Justin and I talked to Tom Hiller of Teledyne/Gavia and got a quick 101 course in GS+, the program that processes our Geoswath sonar data. Side note: Since the beginning of my internship in June I've heard lots of different sonar terms thrown around, but I've been able to sort them out. Our AUV has both a side-scan sonar and a multibeam sonar. A side scan sonar directs pings angled towards the seafloor off both sides of the vehicle, and can detect objects, but not depth. A multibeam sonar directs pings directly below the vehicle, and produces bathymetric (depth) data. When I refer to Geoswath, I am talking about our multibeam sonar. So back to GS+: While I wasn't familiar with most of the specifics, the whole process was essentially applying various filters and corrections to the raw multibeam data. Eventually, you produce a really neat bathymetric image of the area you surveyed, putting the data in a visual, understandable form.
On Friday, I made one last coffee run and the group convened for the final time. We discussed the two groups' missions; surprisingly, the parameters were almost identical. Both ran their lines at a 6 meters altitude, 20 meters apart, at 600 rpm with three cross lines. The main differences were in Geoswath settings, line length and direction.
Everyone put their heads together to brainstorm a list of changes or fixes they would like to see in both the AUV and its corresponding software programs. While the vehicle can already do a lot, there is so much potential for even more. It has been interesting learning about how the AUV is utilized by different groups this week, and I am looking forward to learning more in the future.
Lots of discussions like these in the Boot Camp tent this week.
The vehicle sitting topside.
It was so nice to be able to work in beautiful coastal New Hampshire.
Some Things I've Learned at Bootcamp:
1. Record notes of your operations as you go. Val and Art usually take screen shots of Control Center and create a quick powerpoint while offshore.
2. A patch test is performed to check the latency of the vehicle's two transducers. Typically you check for a roll, pitch, or heave bias, which are biases on differing axes.
3. Avoid running a line along a steep thermocline, because the sonar data will bounce all over the place.
4. Provide coffee early and often. You will get brownie points, especially from the boat captains.
5. There are a lot of acronyms and file types in marine science…with time I will learn them all.
Danielle Ferraro
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