The Code Bender

We've been granted a final chance, which honestly, for the competition is a pretty awesome thing.  It's drug all the teams (and robots) back to the pool nice and early on the final day of competition.  Traditionally Sunday is pretty sparse, I mean, with no "real" reason to be there it's hard to drag college students out to stand around a pool all day bright and early.

We're currently gearing up for our dunk.  We'll have a 15minute run at 11AM PST, and I'll be reporting back immediately after.  We're hoping to be able to take first in the losers bracket as it stands now.  Gate, Bouys, Hedge and a few Paths are what we're hoping for.  Wish us luck!

Time to have fun, but I'll give you the results:

Our run didn't go so hot.  We didn't make it under the gate, I think we still maintain our place from yesterday, more info coming tomorrow probably.

We arrived at the pool at 6:30 this morning and sadly found ourselves 6th in line to hit the practice side.  This meant the earliest we could hit the water without some help would be 10AM.  A good hour and a half after our slotted qualifying time... At first it looked a little bleak, but thankfully due to an awesome gesture by Cornell we were in the water at 7:30.  We found a bad camera cable was in use, critical knowledge before our qualifying run.  Basically at this point, wish us luck, we need it.

After the vision guys performed some tweaking, we hit the water and prepared to see what all SeaWolf could do.  After a few runs of being sent towards various sides of the gate, the diver finally gave us a good start towards the center. We veered a little to the left while we were covering the distance from the dock to the gate, which required a little gymnastics to align with path, but we managed it.  Seawolf headed for the bouy's, bound directly for the red one.  About 5 feet from the bouy, Seawolf went into a sweeping partern... sadly, something like as if it was looking for the next path marker.  She slowly inched her way forward, sweeping from left to right. We were down to 2 minutes on the clock, no time to reset and were just praying for the bouy bounce.  

With a minute left we saw the divers sign that we had hit red, but there was a little doubt which Seawolf saw fit to correct.  After a few seconds of intermittent contact, Seawolf basically sat down on the bouy.  Clearing up any remaining questions of her contact. 30 seconds left.... time.  Seawolf III completed more of the course than she ever had before. That's enough to keep us pleased and as of the standings last night, it was enough to put us in the top 10.

We also opted to try to grab a few extra points yesterday by implementing JAUS, a DoD driven project that acts as a protocol for communicating with unmanned vehicles.  Chris set to work shortly after we were out of the pool and managed to have us up and running to nearly complete state within 2 hours.  The University of Florida had developed an opensource solution to JAUS called JAUS++ and with a little finagaling Chris managed to get it to compile against our own LibSeawolf making implementing the protocol near painless.  In no time we were able to send data and let a JAUS sever connect with us properly, change states correctly, and most importantly, pass data out to the server.  There was still one little bug preventing us from completing the Interop Challenge completely, but we'll have another shot between 8-10 on Sunday.

While the 9th place announcement was reason enough for excitement, Dave Novak had one last surprise for us.  Sunday would play host not only to the finals which the top 7 teams would be competing in, but also to a wildcard round in the morning consisting on a single 15 minute run.  There's a mystery check waiting for the team who is able to do the best, and with only one teams ranked above us by a thin margin so far, we're hoping for the best.

Today marks the true start of the competition!  Last night we were able to choose which qualifying run time we wished to run based on our standings from last year.   By the time it got to us, 12:30 was the latest we were allowed to hit the pool but that gave us plenty of time for an early morning practice run and some debugging time if we needed it.

After a long night for the club 5:30 came early, a necessity after a long nights work if we were going to get everything packed up and make it to TRANSDEC early enough to get a nice early practice run in.  Thankfully everyone is pretty on task and we were making tracks for the pool by 7.  When we arrived we put in for the 8:30 pool test slot and Chris headed right out to start taking some accoustics measurements after some major retooling of how the correlation block was being executed on the blackfin.  Accoustics seems to be growing ever closer to that magical point of actually being able to drive Seawolf!  We're hearing pings loud and clear and are now just working on effectively measuring the delays between when the ping reaches Seawolfs four ears.  These delays will enable us to locate the pinger and hopefully track it down!

The 8:30 pool test wound up being more like a 9:15 pool test due to some delays at the pool and kind of dampened our hopes.  It turns out gatorade bottles don't exactly hold their shape when you fill them with air and submerge them 8 feet under water, meaning our ballasts stopped giving us much flotation.  Seawolfs a bit on the heavy side and losing boyancy was wreaking serious havok on our ability to accurately find and maintain a depth.  While this wasn't much of a problem for the gate mission it proved disastrous for trying to bump the bouy.  Our emergency breach code kept trying attack Micheal 
(our diver for the time) after seawolf would start sinking at depth due to compression and our control code not ramping up quick enough to compensate.  Thanks to Maryland we've now replaced those pesky bottles with some pink foam that seems to be working well (if maybe not a little too well as we've now discovered).

While inspecting Seawolf after the test run, we noticed that one of our Fischer connectors (our class A waterproof connectors) was beginning to corrode.. readers from last year, this might sound a little familiar, and yes, Seawolf was once again performing chemistry experiments.  A solid round of testing by Rabbit found that the aluminum frame that holds Seawolf together was carrying a voltage! After a good deal of debugging we found that one of the connectors had a shield wire touching the outer casing.. we'd found our culprit, the source of our attempts to once again electroplate Seawolf.

After a bit more acoustics testing and some  buoyancy adjustments in the dolphin pool (small pools set up for teams to test in) 12:30 rolled around and it was time to see old Seawolf get into action.   Tetherless Kirk (resident Navy sailor dude for lack of a better description) lowered Seawolf into the water and after explaining our mission start/killswitch system to the diver, the swipe was made, the status light blinked and Seawolf dove.  It quickly became evident that we had overcompensated a bit in the boyancy department, even at when she was at depth you could still see the jets from the struggling thrusters breaching the surface. Due to a cross breeze there appeared to be a current in the Transdec pool, combined with the mistake of leaving her forward speed set a little low and the immense thrust the vertical thrusters were exhibiting Seawolf barely missed making it through the gate deciding to split the right side pole instead.  After two more attempts with various degrees of success and failure we yanked her our of the water, Michael plugged in the tether and corrected our speed issue.  We reset and tried again, this time succeeding in making the gate!  Sadly we never saw the path on the bottom of the pool and got a little hung up looking for it, forcing the restart once again.  We again managed to make the gate but path align failed again.

After a long day at Transdec on Wednesday we headed out to find some food chosing the always popular Baja Fresh.  The trip yielded  some quality food, a reminder of last years adventures (looking at you VT) and an awkward trip around the Carl's Jr. while we had left poor Thunes behind at CVS.  The remainder of the evening was pretty uneventful with the evening winding down uncharacteristically early for the NCSU URC. 

We were greeted to day two of the competition once again by the delightful wakeup call/advertisement hotline the Kona Kai has opted to employ.  I believe that they fail to realize that waking up to an advertisement is a sure fire way to leave a sour taste in my mouth for whatever it is they're trying to convince me to spend my money and  "extra" time on while we're here.

We once again made it to TRASNDEC ahead of our 7:15 unload time and quickly registered for our first pool test of the day.  That's about where things started falling apart.  Once we were in the water we started losing communication with just about everything on random occasion... Our little honey moon with the new and predictable Seawolf was coming to a close and we were starting to see problems of old start creeping out on us.  After a bit of debugging, it turns out, running thrusters and electronics on a single bank of batteries is either a project for grad students or worth avoiding by isolating your thrusters.

It turns out, big inductive loads, make equally big noise.  This meant that from time to time, the USB hubs on Seawolf were eating some crazy voltage spikes, resulting in the IMU and our cameras freaking out in a rather spectacular fashion.  Seawolf was regularly going blind deaf and dumb and worse than that, was having trouble putting it all back together once things had settled down.  Sadly this little problem has cost us our brand new power board... but a quick reworking of our old harness and a DC-DC converter has given us legs to stay in the competition!

While this hasn't completely fixed the issue completely, we're banking on a few zener diodes on the last few points noise could work its way back up the lines to the USB hub.

It's that time of year again, time to let Seawolf do her thing!  After an all night packing/organizing marathon the NCSU URC headed for the RDU Airport at the bright and early hour of 4:30 and began working our way through the maze that is modern airport security.  You've never truly experienced the TSA until you've tried to take a robot and a labs worth of test equipment through an airport while in that foggy, not quite awake, haven't slept in the past 24 hours state.

I wish there was more to tell of the flights, and there probably is, I however managed to catch up on some much needed sleep over the course of the two flights being rattled from unconsciousness only when the passengers next to me required my movement.  Pitfalls of the isle seat I suppose, but well worth it.

Once landed in San Diego we were glad to find SeaWolf, although throughly searched, was still in tact and all of our spray painted boxes had survived the hands of the "throwers" behind the scenes.  Kevin and Dave set off quickly to locate out 15 passenger van, which much to our surprise came back as a much more modest Kia Serento with seating for 7.  A quick game of Tetris and we hit the road and headed for point Loma with a minor distraction of food planned along the way.

We made it to our favorite resort, the lovely Kona Kai, around 2 and just in time for our orientation.  Orientation consisted of the typical, "You're on a navy base, in California, there are plenty of ways to get hurt, please avoid them and don't tell all of our secrets" followed by an unusually short round of Q and A time with Dave as engineers from competing schools grilled him on the specifics of how the course was going to be set up, missions were to be run, and a fair share of questions that didn't need to be asked.  We stayed quiet for the most part, I believe our stance on such issues as course lay out would be more aptly described as reactionary than proactive.

Following orientation, a quick check-in and we were on to assembling our craft.  Thankfully, and much to our amazement, even with the reduced load, there were no major missing components, nothing severely damaged, and other than a utility knife (which.. in reality we had, it was just in hiding) no missing tools!  With assembly and some work on our new cable hiding skirts, Seawolf was ready for action and looking the best she has since we've moved on from SeaWolf II.

The remainder of the evening was spent tooling around for a few parts to complete our new powerboard, finding some food for dinner, and finally locating some much needed sleep with wake up calls coming at 6AM.

This morning certainly came quickly, but thanks to that wonderful 3 hour west coast lag we were all up and moving fairly quickly. After removing a few thrusters from Seawolf to get her to fit in the trunk, we did the impossible (note: this may mean the end of the world is in fact upon us) and showed up to Transdec 5 minutes ahead of our 7:15 unload time.

A quick unload and some short tuning had us up and running well enough to hit the water for the first time this year.  Our first brush with fabled Dave Novak gave us the 8:15am testing slot in the practice half of the pool. Following Cornell we were the 3rd team in the water.  While it wasn't all that visually impressive of a run due to a small bug, we couldn't be happier with the way SeaWolf was performing.  Long gone are the days of futile attempts at making her go in a straight line! (now replaced with less futile attempts to make her dive... but at least it was much more resolvable)  A short retooling period following the first test led up to our second.  Again, while not that impressive to those watching, we collected good data on what the objects we're trying to see actually "look" like to SeaWolf.  After having some navy divers drug her around for a bit we pulled her out and have set out on giving her her last major upgrade of the season, a brand new power board designed by Kevin Wolf and Byron Beddingfield.  A few short reworks of some bad parts and a few load tests later we're all ready to see the days of the famed rats nest we call our wiring harness come to a close and the introduction of a sleek and clean power solution make that last step toward a clean and managed case

Once again AUVSI has managed to fail to provide reliable internet at Transdec, and while not particularly surprising, (I see how providing internet to an outdoor secured navy testing pool could provide some challenges) is atrociously annoying at a robotics competition.  This blog post has been the result of a quick trip back to the Kona Kai for some parts orders and some the need for some datasheets.

I'm sure we'll be in the water at least one more time over the afternoon and hopefully we'll start collecting data for our accoustics system!  I'm planning to update this once a day, but you may also want to check out robosub.org for more up to date information and video recaps starting on Friday!

Thanks for reading,

Matthias Welsh