Sunday, August 31, 2014

Open source rocks, except don't update it

it was dry, but still fun

Having a problem? Look at the source!

One of the awesome parts of working with an open source project is that you can go look at how it works in every aspect. Today I'm working on getting a joystick working with the OpenROV Cockpit and I think this is the file that will need to be modified to add support for a new joystick (and allow for key remapping). It turns out that unsupported controllers work pretty well.

Looking to upgrade? Don't do it!

If it ain't broke ... then don't fix it! I did it anyway. The script has now killed our ROV more than one time. I even left a comment in the file saying not to do it, but I still did it. Now the ROV Dashboard is broken, making it inoperable. Oops, again.

This opportunity forced me to pull down the newest code, fully abandoning the old mess of files at the filesystem level. This means losing my hard-coded IMU tweaks, maybe next time I'll find a way to make that adjustable (thinking cape atmega eeprom). The update should give us some new UI plugins anyway, so hey maybe it will be worth the pain.

That ended up being totally broken with "do not enter" warning signs. So I rolled back to the broken mess, then used git to roll back to a commit prior to the drastic changes to the dashboard. During the update, some nodejs stuff failed to compile, throwing a wrench into everything. In the end these few commands saved the day, for that issue. At least I got to keep my IMU hacks in place on the arduino cape.

tail -f /var/log/openrov.*
cd /opt/openrov/node_modules/
/opt/node/bin/npm install

After all this headache, the starboard motor lost its programming again and makes the tell-tale beeping/braking sound and drives erratically. I guess we'll have to re-program this when we go diving, once the ROV is powered up, at least until we're able to order and replace the ESC for that motor.

Wednesday, August 27, 2014

OpenExplorer AND A TEST DIVE

The founders of the OpenROV project contacted me a little while back about posting on their site,, to document our adventures with the ROV.  I was hesitant to post anything there until we had a working ROV, so for a long time I haven't moved on the idea.   For anyone that has been reading this blog for a while, you know this isn't out of lack of desire.  We have put so much work into this project, and have had our fair share of setbacks, so it hasn't always been easy to keep the fire burning on this. As someone new to the maker world, I wasn't sure what to expect but I definitely wasn't expecting this much work.   But our hard work has finally paid off.   I can now say that after tonight, I am so happy to announce that we are finally up and running!   We completed a full underwater test and everything on the ROV is working!   Lights, lasers, motors, all works.  The motor programming stuck.  The lasers toggled on and off accurately ( funny story, we are idiots and thought the lowecase l for lasers was a forward slash, so they were working the whole time we thought they were broken) and even the depth hold command is working accurately.  We are finally ready to rock!!!!!

Next step is to practice deploying and flying in a pool. Video of the ROV flying in action to come.  I just couldn't wait to share!  Really really exciting things to come now that we are up and running, thank you so much to our friends and family that have encouraged us along the way and to the new friends that have come along and followed our adventures!  So in conclusion, we are now live at on the site and will finally move from the building to adventuring phase.

Thanks for reading so far, and here's to great things to come!

Ready to dunk

Video feed is up

Here goes nothing...

There she blows!





Live feed from the camera after dunking.  Still working!

More testing.  Still working like a champ.


Using washers provided by Danny as ballast.  They work brilliantly, and are relatively easy to adjust.  Awesome!

One last shot of her in the water.  We're done!

Saturday, August 23, 2014

Lube something something

one must lube the tubes

The port battery tube wouldn't seat properly. It turns out that the o-ring was dried out. I lightly filed the edge on the tubes and caps and applied oil to the rings. 

Now both tubes are easier to open and close and the seals look much better.

Also pictured is the untested ballast correction on the starboard side. We hope to figure that out next week. 

Saturday, August 16, 2014

Grinding for mine

Tonight we spent time cleaning up the excess epoxy potting and re-testing the motors. Before grinding, these motors tested as electrically waterproof but that was before the propellers could be attached.

Richard trimming away epoxy potting

As long as we don't trim too much epoxy off the motors they should stay waterproof.

But they didn't. On one motor we lost all electrical insulation to the water.

electrically leaky motor

We hoped that touch-ups on these tiny spots on the motors will recover the electrical insulation and still allow the propeller bells to fit over the motors.

... And they did! The motors now show infinite electrical resistance to water and the propellers fit.

back side closeup of potted ROV motor

front side closeup of potted ROV motor

Thursday, August 7, 2014

New openrov video

It helps me stay focused and committed to see a reminder of what we're building and contributing to.

Monday, August 4, 2014

Excuse me while I drip this out

James' previous post was referring to this article regarding re-potting our brushless motors. So, did it work??

We're not sure yet, but it certainly got better.

If we were experienced scientists already we would have written down the readings we took prior to re-potting the motors. But we didn't. My vague recollection of that evening was "it should have said zero but didn't" and I was too excited about finding the problem to remember to save any data. We think we saw readings from 0.09 to 0.20 Mohm on all three leads of all three motors and on one of the battery leads.

First we had to peel and pry off all of the blue tape epoxy molds.

James de-casing the freshly potted motors

Then the epoxy required trimming as expected. We will have to touch this up later.

The epoxy missed some spots

Did we get better electrical results? Maybe! It seems like we did, anyway. Our numbers from this round were 5-15 Mohms. We think we can improve on this number with some epoxy touch-ups. 

We also tested the previously repaired battery tube wire which no longer shows leakage to water. Yay!