Monday, May 23, 2016

360 360

We returned to the 360 bridge for a second dive.  The ROV got stuck, the tether got stuck, one propeller came off and another got tangled up.

The flashlight looks tough but didn't quite work out.  We need to add some buoyancy to the light to make it neutral.  It was too heavy for the ROV in this state. 

The ROV performed as expected, turning left and flying like a brick.  One motor wouldn't spin in reverse, per the usual.  We did not opt to open the main tube to re-calibrate the ESCs and limped it along (like last time).  

The shelter of the bridge provided birds ample opportunity to poop on us and our gear.  On the plus side that new strap kept the main tube completely dry, so yay!

Key takeaways:
  • compass is much more smooth (but incorrect)
  • IMU hacks still work but the file name changed to CMPU9150.cpp
  • vertical propeller came off again (already fixed)
  • payloads need to be neutrally buoyant 
  • stop diving where people go fishing!

Future plans:

  • double o-ring seals on battery tubes (ours leak)
  • keeping main tube sealed to minimize moisture

Thursday, April 21, 2016

Double Tap!

We've reprogrammed the esc's on the ROV endlessly, and calibrated them endlessly, in our attempts to get it to fly correctly.  While upgrading the software and firmware last night, we noticed something that is going to make flying it a lot easier.  Often we've found that using the steering keys to send inputs to the esc's produces unpredictable results - sometimes the propeller will spin correctly, sometimes not at all, and sometimes will cut out unexpectedly.  Last night we discovered that double-tapping the keys was effective 100% of the time, even after reboots and power loss.

So, it still flies like an underwater brick.  But at least we can control our underwater brick predictably now.  I'm calling this a victory.

Our next dive is coming up soon -  heading to Barton Creek to find and video underwater wildlife in early May.  We'll have some upgrades to roll out by then including a new cinching strap to keep the main tube sealed, and a 4000 lumen torch to increase our low-light capture with the GoPro.  Exciting times for AustinROV.

We also upgraded the OpenROV software image which greatly improved the compass stability.  Our IMU still thinks it is upside down though...

--DannyE can't comment without a G+ :(

Saturday, April 16, 2016

When you fail so much it feels normal

We flew the ROV at the boat ramp at the iconic Loop 360 Bridge.  This picture was before the rain.

During setup we discovered problems with the laptop.  There would be no screencast recording for this dive.  We're off to a rough start already.

Richard is installing our freshly charged and brand new batteries.  They worked great!  Runtime is a little over an hour per set of six batteries. (11,000mAh 3s LiPO)

We saw a fish! 

Lots of fish, actually.

The gopro once again didn't capture much, this time it was due to the low light conditions and murky water in Lake Austin.  We need either a much better low-light camera or a much larger light source with the gopro. 

This also happened.

Other highlights:

  • vertical propeller slipping on the shaft stranded us at the bottom
  • fishing line tied up the starboard propeller
  • main tube flooded after desiccant swap (dirty o-rings?)
  • reached maximum depth of 4.7 meters 


Tuesday, April 5, 2016

Lou Neff Point - Best dive yet!

Two weeks ago we had our best dive to date! We took the ROV out to Lou Neff point to see what type of wildlife we could capture on the cameras. I'm happy to say the dive was almost a complete success!
We did't bring the correct seal, so this is Danny's attempt to fit a smaller one on the port battery tube.
Danny & Jim doing pre-dive checks.
It's hard to complain with that view!
Jim searching for wildlife.
We captured a turtle! SUCCESS!!
Danny's expression explains how we all felt about this dive!

Do you remember, from above, I said this dive was almost a complete success? With so many components on this ROV, we were bound to have some type of an issue. Sure enough, after 45 minutes of exploring Lou Neff point, and right in the middle of my piloting session, the ROV died. Once we reel it back in we notice that one of the batteries has completed died (I mean D.E.A.D.). It has been quite awhile since we bought new batteries, so losing one is not that hard to imagine.

Next steps:

  • Buy new batteries
  • Find the battery tube seal
  • Continue this dive's success!

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Sunday, October 4, 2015

For real this time

We took the ROV to the San Marcos River today at La Isla. This is sort of how it went, though it doesn't tell the whole story.

The reality is that for most of the time we could only see a blue abyss, even in bright daylight and clear water.

By the end we had collected some water inside the main tube and called it a day.

Steering was still a huge problem. The ROV always wants to go left. No matter what. We have swapped motors, propellers, tried inversion settings and updated the software to try and solve this problem to no avail. Our newly joined member Evan suggested we try a fixed-position rudder. We may just do it. I am willing to try almost anything given how bad this neutrally buoyant brick flies.

San Marvelous

Road Trip!  DannyE drove us down to San Marcos, TX to test the ROV out in the crystal clear water of the San Marcos River on Sunday.  It went surprisingly well, as far as things for the ROV project are concerned.  First of all, the day was gorgeous:

The dive staging area

We set up shop on an island in the middle of the river, by Rio Vista park.  The island is accessed by a small concrete bridge - carrying a bunch of electronics across that bridge was fun stuff.  The ROV may be waterproof, but most of our gear certainly isn't.
In any case, after setting up and and clearing our pre-dive checks, we chose to launch from this choice looking spot:

Our launching point - a tiny pier and some beautiful water

The goal was to dive in the still area between the fast flowing water on the southern side of the island and the slower (yet still powerful, compared to the ROV's motors) current on the northern side.
And dive we did!

Thar she blows!

Safe to say the San Marcos River was far more powerful than our little robot.  We explored the immediate environs but were swept away by the current repeatedly.  However, we seemed to draw quite a few curious onlookers, including human, piscine, and testudine ones.

Oh, and we saw a really special creature breach the water at one point:


Oh hi

We took a lot of video both from the ROV and the GoPro attached to it.  We'll be editing video and throwing it up here soon so that everyone can see what we're seeing while the ROV is underwater.  We think you'll like it.

We are also really looking forward to diving in some calmer waters more suited to the ROV's power level - namely, lakes like Lake Buchanan.  We are in the planning stages of an exhibition there soon, to look for remnants of the lost city of Bluffton.  Whether we find it or not, we're finally able to use the ROV out in the real world and it feels pretty darn good.  More to come, soon!

Wednesday, September 23, 2015


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.