Highlights of Rex2 Footage

Tuesday, March 31, 2009

Dylan is working with the Reef Explorer 2 (Rex2) in Hawaii. He just posted this video of some of the best recorded footage.

There were quite a few sea turtles curious enough to swim up to the vehicle.

Image Capture from a Basler A102fc in Linux

Monday, March 30, 2009

Even though this image is nothing to write home about (by photography standards), it's one of the first I was able to capture using a Basler A102fc -- a firewire camera that we use in our vehicle.

Capturing this image in Windows is fairly straightforward; they provide a driver disc and some sample code. In linux, you need the libdc1394 library and some patience.

Before even getting to the point where I was worried about software, the first hurdle was how to power it on. The camera gets power from its 6-pin firewire port (4 pins for data, 2 for power) but my laptop has only a 4-pin port (no power).

The first idea was to pick up a powered firewire hub from the local electronics store. However, this led to a lot of frustration on my part before discovering that a powered firewire hub does not ... actually ... power ... firewire. It just amplifies the data signal so it can be repeated on the other ports!

One cannibalized firewire cable and 9V power supply later, I had my own powered firewire hub.

The software took only slightly less time, as the documentation for the libdc1394 library covers versions 1.x while the library itself is up to the non-compatible 2.x. However, I made great use of an existing project called grabdma.tgz.

After finding the details of the video mode I wanted using coriander, I set the proper image conversion function (the camera returns YUV images, not a Bayer pattern) and everything fell into place.

Opening the Main Pressure Housing

Wednesday, March 18, 2009

The majority of the electronics inside the Odyssey IV are inside a glass sphere near the top of the vehicle's interior. Today we opened the sphere to do some work calibrating the RTU.

There is quite a lot of stuff packed into this 17" diameter space, including the PC104 mainboard, 2 large thruster motor controllers, and the RTU controller. The water cooling system you see here is actually for the thruster controllers, not the main CPU.

With the top half of the sphere removed, you can see the method we use to quickly disconnect the inside of the sphere's penetrators from the rest of the electronics.

New Hires

Tuesday, March 3, 2009

I'm one of two new hires to the MIT AUV Lab (along with Seth Newburg).

This lab is where our vehicle lives when it's not in the water.