Once again I woke up in the morning to the sounds of activity. Apparently there were concerns I might be dead due to my sleeping so deeply, but my new found consciousness washes away their concerns. We are packing up to meet up with the MechE team who is already at the Transdec. The crucial o-rings we need to finally seal Aqua URSA seem to have been shipped to every possible location except our hotel; however, we should be receiving them shortly. A message to Veselin informs us of a new development; the MechE’s need a new power drill since we have effectively killed our current battery.
Once arriving at Transdec we unload SubmURSA to join Aqua URSA at our tent. Our run is scheduled for 1:30 today, and it is already approaching noon; time is short and we a lot of work to do if we want to qualify today. The MechE’s are busy ensuring that SubmURSA is water tight for the trip, and also continuing work on Aqua URSA. Next to me Lee stares intently at the filter board, possibly figuring out how to mount it onto one of AU’s brackets. His temperamental board now has electrical tape wrapped around it in an attempt to keep the resistors snug in place, but the horrifying truth lingers on the fringe of Lee’s fraying mind. On my left Veselin continues to pour over the code.
Our scheduled slot comes up quickly and Mike runs off to try and buy us some more time, perhaps to swap spots with another team. We manage to get the time pushed to 2:00 and turn our attention back to getting SU sea worthy. The coordinators come by and inform us that they are a little behind and ask if it would alright to do our run 20 minutes later, to which we obviously have no objection to. Alas, despite all our extra time we are unable to get SubmURSA to a proper working state to even think of entering the water. Despite this fact we continue to work towards getting some testing in the dolphin pools.
Veseling and Mike continue to try and get things working, but like Jurassic Park systems seem to be dropping dead by the minute. Scott and Rumman return from acquiring the coveted o-rings to seal AU, as well as a trip to Radio Shack for some much needed components. Since the camera case holds two usb cameras, but we only have a 4 pin SubConn connector to enter the waterproof case. This means we need a usb hub. And that’s just what we bought. It won’t quite fit in the camera case so I will have to make some modifications. With Scott’s help, I bust open the hub’s casing and expose the inner circuitry. After some time of soldering I manage to remove the four usb receptacles. Mike hands me two cables that will be used to connect to the cameras. I now have to somehow connect those cables to the now bare spots. Stripping back the obscenely small wires it occurs to me that I may need to have 8 arms to accomplish this task. Scott is kind enough to lend me his arms for the moment. Together we painstakingly solder in the new cables, several times I might add; they were stubborn to get in place. A quick test with Mike confirms that the new cable works perfectly, the first time something has gone right for ARVP thus far.
With this now completed, Rumman and I finish the last components of the motor controllers with our purchases from Radio Shack. Next to us we hear a sharp BANG, and Mike jumps back a few feet. A plume of smoke rises up from SumbURSA’s pressure vessel, and the depressing smell of fried electronics fills the air. Mike and Veselin trouble shoot to try and determine what has been destroyed among the giant mess of wires inside the heart of SU. Meanwhile, Lee has faced his fate and decided that the headers holding the resistors need to be removed. He and Rumman had attempted to coat the resistors with tin in order to thicken them in hopes they would fit more snuggly, to no avail. Lee now painfully desolders the headers from the perf board, a task that will inevitably last him well into tomorrow.
SubmURSA has now seemingly cannibalized Aqua URSA. Having acquired AU’s compass tail, SU is now a full two feet longer than normal causing it to occupy most of our work bench. It also contains a mix of old and new electronics, at this point we are doing our best to simply get into the water. I will jump for joy if we ever get to see it properly submerge on its own. Every simple task seems so far away now.
Back at the hotel Mike and Veselin continue their vendetta on SubmURSA. Lee occupies a corner to continue his silent mission. I cross over to the other room to assist the MechE’s with putting the final seals onto the endcaps. One end fits just fine, but issues with the other force us bevel the edge; that solves the problem, and now at long last the endcaps of SU have been sealed. The celebration is short lived once we discover that connecting the depth sensor to the casing prevents the electronics tray from fitting properly. It will take significant modifications to solve this problem, but as engineers this is what we are trained to do: solve problems in innovative ways. We have limited time and supplies but we’ll make it work.
I decide to take my nightly walk to reflect on the day and to see what the other teams are up to at the hotel pool. The area is overflowing with activity; five or six teams have their robots in various corners of the pool performing tests. When I return to the hotel I learn that the MechE’s are preparing to do a dunk test for AU. I’ve been waiting all week for this and join them in earnest.
Diving into the cool pool with Alvin we prepare to receive the platform. For the first time all week, ARVP breaks the boundary between air and water. Without all of the thrusters and other components attached it takes the two of us to force AU under the water. A few dunks and we check for leaks. A small pool of water has formed inside the chamber which is bad news for us. We hope this is due to a loose connector and not the main seals. Scott tightens the connectors and we try again… Still leaking. But this time we believe we have discovered the source. The access cap is not seated properly. A small thunderstorm scares most of the other teams inside, but it lets up soon and we continue our work. A few minor adjustments and we attempt to drown our submarine once more. This time we come up dry after several attempts. Success!
As I climb into bed to begin logging the events of the day I discover my sheets have been littered with solder shavings. I have no idea how they got there but I am by no means surprised. Across the room Veselin asks if I should be awoken once they get SubmURSA into the water tonight, a bold proposition at 2am. Just at that moment, another snap, smoke, and the smell of burt electronics. Mike stands over the open vessel dejectedly as we’ve now fried another of the old motor controllers. I jump out of bed to help Rumman quickly replace the fried component.
Lee abandons his task of replacing the headers for the filter board, having completed half of the task over the past 12 or so hours, and retires to bed. Mike and Veselin continue their constant tugowar of progress with SubmURSA. Across from me, Rumman is fabricating some connectors. From the other room I can hear the drone of Scott’s snoring and the metallic clanking of the remaining MechE’s working on assembling the electronics tray for tomorrow. A quick check reveals Alvin is also asleep, leaving Mikey and Michael (or the Ninjas as we’ve come to call them) as the ones still working. The show me that the tray is finished, having managed to work out a solution to the depth sensors annoying presence in the interior. The tray is now ready to be populated with our boards. More good news to offset the constant storm of setbacks and issues we’ve encountered today.
Just as I am returning to bed to retire for the night, Veselin informs me that they are ready to head out to the pool for some testing. It is 3:30 am at this time. I’m baffled at how we managed to accomplish this, but better late than never. So I head out to the pool for the second time today. This time instead of with the MechE’s and Aqua URSA, it’s with my team of EE’s and SubmURSA.
At this time of night, what little heat the overcast skies had offered the pool is now most certainly gone, leaving the pool icy cold. So instead I decided to chill in the hot tub until they are ready for me to accompany the sub into the pool. Veselin now is in full work mode. No longer leisurely laid back stance programing on the bed I have grown accustomed to seeing, he now leans forward intently. I’m sure if Veselin could stick his head straight into the computer screen and become one with the code he certainly would. Mike stands watchfully over his shoulder and Rumman at his side.
After what seems like forever, they demand my presence in the pool and I quickly oblige. Despite all the problems we’ve faced today, and even the triumphs, this is the most exciting moment. Rumman looks on with the camera as we lower SubmURSA into the pool. Though I had just done this hours before, this is different, this time we have electronics.
The thrusters have some issues at first; both they and the compass require some attention. It seems like seconds of action are interspersed with minutes of waiting in this icy pool. I tread water to keep warm while all three of my team members stare uniformly at the small glowing screen poised on Veselin’s lap. After spinning SubmURSA in a few circles to calibrate the compass, we are ready to test the thrusters. Unfortunately the submerging thrusters are not powerful enough to force the sub under the water. We try removing the ballasts but that makes it too heavy and Mike has to prevent it from sinking; a prospect that at some times this week might seem preferable to the pain and heartache we’ve had to endure to get here. For the time being we’ll have to deal with SubmURSA forgoing its namesake and simply floating atop the water. Next we test the forward thrusters and the heading calibration. After about a dozen laps of the pool the sub is travelling in a surprisingly straight path. It starts to show signs of rain, so after a few quick depth tests we decide to pack up and leave.
Settling back into our room at almost 6am, Rumman and I decided to stay up the extra twenty minutes it will take to get breakfast from the hotel. We both order giant platters of food: pancakes, eggs, bacon, omelettes, and really expensive orange juice. Practically passing out in our seats already, we finish our meals and return to the room where Lee is awake and preparing for the day to begin. A quick briefing of the nights events and we turn in for the morning, leaving him to take the reins.
Our last chance to qualify today, let us hope SubmURSA has what it takes to get us through the gate.
ARVP Electrical Team
University of Alberta