Last week we had just received the UD-134 glider (aka the “Blue Hen”) from two tours of duty in the Gulf of Mexico in collaboration with IOOS and Rutgers University for the Deepwater Horizon Oil Spill Response project. To prepare for an upcoming Antarctic mission, we needed to get some work done on UD-134 at the source – Teledyne Webb Research in Massachusetts. Since we were only five hours south of Webb at the time, I loaded the Zune HD (with purely educational podcasts of course – in this case Security Now) and it was road-trip time for me and two of the students from the ORB lab.
The students who went with were really excited to get to learn from the masters while we tore down UD-134 at Rutgers. (For those new to gliders, Rutgers is the undisputed kings of the glider realm, they’ve been flying them since, like forever). One of the students who came with was a summer intern who was charged with learning how to pilot the Glider over the summer. Because of the last-minute deployment of UD-134 in the Gulf, he had lots of pilotting time on a simulator, but not so much hands-on with real Gliders. The other student was a new grad student who would be responsible for ingesting and processing glider data, so she was looking forward to the trip as well. When we decided at the last minute to head up to Webb Research to deliver the components, the intern said he “felt like Willie Wonka with the winning ticket to tour the chocolate factory”. He was definitely not disappointed as Peter Collins met us at the doors of Webb and gave the students and I the grand tour.
Peter Collins (aka “Texas Pete” for this post) donned his cowboy hard hat and headed to the ballast tank with me and a couple of our students last week to do a quick talk for Ocean Bytes. Pete gave a quick introduction to the Slocum Electric Glider – an Autonomous Underwater Vehicle (AUV) or Underwater Glider that is made by Teledyne Webb Research. Take note that the glider that Pete has in front of him as it is a tad different from most in that it has two science bays (there is usually only one). This one is being fitted with a Photosynthetically Active Radiation (PAR) sensor and a FIRe sensor (remember Lauren’s video?) from Satlantic. I’ll hand you to Peter now so he can discuss what a glider is for and how it works…
In addition to the lineup of first generation gliders, we were introduced to the second generation gliders that are just now being manufactured – also called the “G2” gliders. I’ll try to cover everything that we learned about the G2 systems in a future post.
Thanks again Peter for the awesome hospitality and for taking such great care of us!
Note: Getting lots of inquiries as to where one might obtain “Cowboy Hard Hats” – Peter provided a couple of links to possible suppliers – Link 1 and Link 2.
Some students and I went on a road trip to Rutgers University in New Jersey and then ended up heading up the coast to East Falmouth, Massachusetts to meet with the fine folks at Teledyne Webb Research. During a tour of the facilities, we were introduced to the APEX floats, whose data (through the ARGO program) the students were accessing for various projects in the ORB lab. James Truman, an engineer at Webb, graciously agreed to do a quick 101 overview of the APEX on camera.
Profiling floats like the APEX are able to sink or float by varying their internal volume. A standard equation for Buoyant Force is:
F(buoyant) = –pVg
where p=density of the fluid, V=volume of the object (in this case the float) and g=standard gravity (~9.81 N/kg). By adjusting the internal volume of the float by pumping fluids in and out of the interior, we are able to make the device either more or less buoyant. There’s a really neat cut-away animation on the UCSD Argo site that shows the guts of the units quite well.
Float technology has evolved rather quickly, with the original floats only serving as a mechanism for tracking deep ocean circulation – also called Lagrangian Drifters or ALACE (Autonomous Lagrangian Circulation Explorer) floats. They would pop up to the surface and transmit back their positions and the temperature at depth. Using the drifters last known position and its new position gave scientists an idea of how fast and in what direction the deep ocean currents were moving. Later these drifters were equipped with CTD sensors (Conductivity-Temperature-Depth) and they took sensor readings all the way up the water column and transmitted a “profile” reading back to the mother ship. These were called PALACE or “Profiling ALACE” floats (see WHOI’s site on ALACE, PALACE and SOLO Floats).
NOAA has a site called ARGO KMZ Files that makes it really easy to get started tracking ARGO floats and their data. You just need to install Google Earth first – which can be downloaded at: http://earth.google.com/. Below is a screen shot of the ARGO floats in the Atlantic.
Thanks again to James Truman and the awesome people at Webb Research for taking us under their wing and spending a lot of time showing us the ropes. It was an excellent experience that the students are still talking about.