Robosub is now over, and since we're all finally home safely we have time to post an update.

Our qualifying run was enough to get us into the finals, which were on Sunday the 22nd. That morning we loaded Tortuga into the truck as usual.

We had done some repairs to the sonar system the night before, so we used our practice run to test it out. We had the third slot for the final run, so as the time neared we made our way to the dock for final preparations.

Tortuga was loaded onto the crane and placed in the water...

...And the run began. We made a run for one of the uprights on the first couple attempts, but some interference was confusing Tortuga's magnetometer.

Our software team decided to pull Tortuga back for one final attempt and go straight for the sonar task.

Unfortunately the clock ran out before she could reach the octagon, ultimately putting us in 6th place for the competition. Out of about 30 international teams, we think that's a pretty good place to be.

Thanks to all of our sponsors and fans for their support in helping us get through another year. RoboSub is a massive undertaking, and we couldn't dream of doing it without your support. Special thanks to our two graduating team members:

• Kit Sczudlo, who will be working for Amazon in Washington soon
• Gary Sullivan, who is currently working at Wabtec

Best wishes for your future careers. We'll miss you guys!

For now we're all going to take a break and get some rest, but you can be sure that when the 2012 fall term starts we'll be back at it preparing for next year's competition.

Lots of updates today. Yesterday was mostly a day of steady progress in testing Tortuga's software. The testing doesn't even end when we leave TRANSDEC; last night and the night before we tested until Tortuga's batteries ran out.

Today we had our first semi-final run in the morning. The team was feeling a bit apprehensive as we prepared to put Tortuga in the water.

We ended up pulling the sub back twice, but on the third run we accomplished everything we intended.

The symbols represent the tasks we completed; our line shows we passed through the gate, over two paths, through one set of uprights, we surfaced in the correct octagon, and picked up and dropped the wreath(you can see what all of the tasks for this year are at  the RoboSub website). We are happy with the results, but of course the competition isn't over yet, so later in the day it was back in the water for more testing.

The robot's software is constantly being updated, so after a run Gary, Eliot, and Stephen (the software and controls team members) will discuss what changes need to be made.

In-between intense practice runs, sometimes we even manage to have fun. As the competition was coming to a close for the day, Kit decided to see how many hats he could collect. There were contributions from our competitors Cornell and ETS, as well as an AUVSI hat to top it off.

Tomorrow is our second semi-final run; we're going to see if we can complete even more tasks and really cement us a spot in the finals.

Today we were able to pre-qualify Tortuga by autonomously navigating through the first gate. Our software team then spent the rest of the time taking video footage of the course to process later, so we can teach Tortuga's vision algorithms what to look for.

See Tortuga head home:

After the competition closed for the day and the team had dinner together, Tortuga went for another swim in the hotel pool for more testing. We were very happy with the results, so we're all set for full-scale testing tomorrow, as well as the first day of static judging.

We know its been a while since the last real post, but we've been working hard to get Tortuga ready for competition.

All summer we worked to upgrade Tortuga IV so it could take on the new challenges of this year's Robosub competition. Most of our upgrades are incremental, so you could call this Tortuga version 4.1. Physically, the biggest change is the overhauled actuation system.

Last year the mechanical team replaced our hydraulics with a small pneumatic system. It worked so well that, for this year, they enlarged it to run all of our manipulators.

All of the AI has been re-written to work more efficiently and be easier to change. The software team has also been working on new vision algorithms.

Last Sunday we flew out to San Diego to prepare for the competition. This year's hotel for RoboSub is the Sheraton San Diego, which has provided us with large rooms in a prime location.

Of course all that extra space gets taken up by our tools and spare parts (not to mention Tortuga herself).

Shipping was not kind to the robot this year, so right out of the box we had to make some repairs.

Electronics in particular had a difficult problem, but thanks to quick thinking and lots of hard work the robot is working great.

Currently the software team is chugging away at our AI as mechanical and electrical prepare for another practice run later today. We're on track to pre-qualify, then testing, testing, and more testing.