AustinROV

Welcome back!  We have updated the blog name to reflect the new mission of the group.  Just because we've moved on from our original goal of exploring Jacob's Well, our focus on doing citizen science and exploring with the OpenROV project is still alive and well.  We're exploring a lot of interesting possibilities for underwater dives in the Austin area, including underwater ghost towns in the Highland Lakes chain, and are excited to start planning some of these expeditions out.  We plan to continue blogging about both the technology challenges we encounter with the OpenROV platform as well as detailing any finds we make along the way.  Thanks so much for reading the blog so far and we hope you continue to follow us on our underwater journeys.

Three good tests

The OpenROV team says "you can build it in a weekend" but to us the reality was much closer to 18 months. I think this is an example of how "dreamy" the OpenROV folks are. They have very lofty ideas but execution always leaves something to be desired.

A short example, the next version up from 2.5.1 is version 30.0.0. Maybe they fudged the version number, something that could be corrected, but they went ahead with it. It isn't all that revolutionary or a silver bullet for the 2.5.1 problems, just an incremental change.

Ah, the perils of being an early backer of an open source project. The upside is that things improve all the time, like software. The downside is that as things improve, you are stuck with the "old world" hardware and software you started with. We bought LiPo batteries for our 2.6 kit, and very soon after we found that there was no way to use them, the OpenROV team switched to a new LiFePo battery type requiring all new ROV geometry and chargers. We decided to stick with LiPo and went with a much higher current 26650 battery.

Finally, we are ready to actually dive our project OpenROV. It doesn't fly perfectly but we think it is about as good as it can get with this platform. We've fought software, firmware, hardware and collaboration issues to get here. Now that we're ready, the place we thought we were going seems to have slipped further out of reach.

Sadly we probably won't be going to Jacob's Well. This is partly because we can't rely on the ROV being able to get back out of the well and the JWEP makes our efforts redundant. It is also worth mention that we couldn't get ahold of anyone at JWNA or Wimberly Valley Watershed to even discuss our project.

Don't use SUDO while underwater

This will be a text only update.  If you're wondering why - well - somebody erased all the latest GoPro footage (that would be me, James.)  We had a nice little test dive going this past Saturday - a tune up dive to tweak the controls (they're still difficult to use) while we wait for the summer swimming season to die down and for someone/anyone at Jacob's Well to respond to our inquiries.  Early in the day, I noticed we had already filled up the GoPro storage - I had neglected to erase the last few dives worth of footage, so I decided to format the card and just capture more footage for the rest of the day.  Great plan, right?
Unfortunately, we got no more footage that day.  There was a leak and the ROV started going nuts on us.  We thought perhaps our code tweaks to the motor controls tanked it, but it wasn't actually errant sudo usage but a bad o-ring that sank us.  Anything that can go wrong on this project will go wrong.
After letting the ROV dry out, it was working fine again, but we were done for the day.

So next up, if anyone reading this knows someone that can get us diving access to Jacob's Well, that would be amazing.  So far, we've gotten nowhere with them.  I'm not above just driving there with the ROV in the offseason and diving it, but I'd rather do this with the cooperation of the county and all.  We're as good as we are going to get piloting this thing - it's time to dive.

Bout Time

Well...we finally got this robot working.

I can't quit you

If I had known...if we had known...before starting, how many difficulties we'd have in just the building  of the robot, we'd have been stunned.  The OpenROV team had me hooked way back when, with their kit that "can be built in a weekend."  Here we are a year later, finally getting to that point.  There have been a lot of lessons learned in this endeavor and I won't detail all of them here, since we've been covering them throughout the course of the blog, but a few things are worth touching on:

• Hobbywing ESC's are a pain in the arse
• Danny E likes to cut, burn, and hammer on things
• But he makes them work
• Piloting a robot in the real world is NOT just like a videogame
• Building robots is even more fun than you'd think, when all is said and done

We navigated a little homebrew obstacle course in the pool to do some pilot testing and get a feel for how the OpenROV will handle in tight spaces.  It's a little scary how tough it can be to pilot in the pool; some of that is due to the currents being pumped around, and the relative lightness of the ROV.  But it's also just tougher than it looks.  We bonked the GoPro on the obstacle course more than once, and sometimes even getting our bearings straight was a hassle.  But we we able to fit the ROV through some tight spaces and we think we're ready to do this.

Next step is to make this official with the Jacob's Well people; we are hard at work on securing a date and time to take this little guy out there and see what we can see.  It's finally coming together!  

The best ESC in China

Oh, the pain you have caused me, hobbywing.


I declare that Hobbywing is *NOT* the best ESC in China. At least not all of them are.


We've replaced these already with identical parts only to have the same problems again. Now the trouble seems to be one ESC losing calibration.

Our little ROV has been through a lot. Just getting it to the test dives has been a huge challenge. We have seen software, firmware and hardware problems in and out of the water. Operator error has contributed. Our group has become fatigued with the motor issues.

This motor had failing bearings that were potted in, requiring replacement.

Richard potted a replacement motor and then we damaged one of the brand new motor bearings.

This probably happened while removing the c-clip that holds the shaft in place.


Oops.


Arthur provided some much needed new bearings. Danny soldered the motor onto the ROV. Alas, there was still no joy to be had. Now the motors are behaving unpredictably again.

After removing power via the battery tubes some, all, or none of the ESCs lose their calibration settings (they all kept their programming, so yay?). This is evident because the motors will then not spin backwards. Re-calibrating the ESCs works and stays fine through reboots but does not survive pulling out the batteries.

More and more the Blue Robotics thrusters are looking like our next steps, probably even with their ESCs. but we still plan to limp the ROV out for another test dive very soon.

These Poolish Games

Test Dive #5 is in the books.  

We set up an obstacle course underwater on Sunday to attempt to navigate and put ROV in the water.

Obstacle course sighted!

  We started flying, and immediately noticed that our balance in the water was way off, so we started working to adjust our weight distribution to get the ballast correct.  Turns out that split-shot sinkers from a fishing tackle box worked perfectly for this!

They have upgraded from catching sunfish in the river to ballasting an ROV - a huge promotion in a fishing weight's life, I'd think.  

Adjusting the weights 

Back in the water we went.  

Thanks to David H. for hosting us at his apartment pool again!

Some of the team chats with David while rebooting the ROV

Here's the part where things went wrong.  One of our pre-flight checks on our checklist (yes, we print out flight checklists every time we dive...it is important to be thorough!) is to check the seals on the tubes.  This is important because apparently you don't want water inside the main electronics tube of your ROV, who knew?  But what we didn't do was check the seals again after adjusting all the weights on the ROV.  So although newly balanced, we sprang a leak.  I think it came loose when we moved the tube around adjusting the weights.

So yes, you are correct, that is BAD NEWS BEARS.  

Bleh...water inside

It went down something like this.  I (James) was at the controls, wondering why we couldn't fly straight, just looping in circles.  Danny and Richard and Arthur were calling out to me to stop spinning in circles.  Someone noticed that there was fog in the main tube.  We pulled the ROV out of the pool and...well, yep, it's now about 5% full of water, enough to puddle up in the corner.  

The good news is that we never lost the video feed or the Cockpit from the ROV, so it still works.  The bad news is that obviously our dive was over for the day.

Drying off

Since we were gathered up and Arthur had brought some pro video equipment, we recorded some interviews we hope to incorporate later into a video we're making about the entire experience.  

The Interview that North Korea didn't want you to see

It takes a lot of gear to do things our way

Some positives we gain from this dive are that we had more control time underwater than ever before, thanks to our new LiPo batteries.  Next steps are to fix our trim issues so that we can fly straighter underwater, and to attempt the obstacle course again.  

austinrov documentary teaser

None of us are filmmakers today but we're learning. The team worked on our interview questions and filming techniques today. Lots of footage was captured. Here we present a teaser, only a very small taste of the fun we had.

AustinROV teaser from Daniel Epperson on Vimeo.

We verified that the new batteries and camera servo were working as expected. One of the ESCs lost programming but it wasn't noticed or fixed. That might come back to haunt us later however it will be an easy fix.