Experimental ROV Design using Blue Robotics Components

[SSN626B]

Hi All,
I have now soldered the BlueESC power cables to the Power Distribution Board and have also soldered the Power Cable from the Electronics Tray WTC to the Power Distribution Board. Pictures are below:

Power Distribution Board with BlueESC Power Cables Attached

Power Distribution Board with Power Cable Attached

My biggest concern now is sealing the solder joints and cable jacket entry points on the Power Distribution Board. Several Liquid Tape users have had success using it as a form of "conformal" coat. They said to apply thin layers of the Liquid Tape letting it dry thoroughly in between coats. The other approach to sealing would be to make a small dam around the Board and coat it with a layer of epoxy resin.

Comments on how to proceed are welcome.
Regards,
SSN626B/TCIII

[SSN626B]

Hi All,
Due to the holidays, progress has been somewhat spotty, but I have made some progress nonetheless.
I have coated the Power Distribution Board with eight coats of MG Chemicals 4229 Connector Coating2 allowing at least four hours of curing time between coats. The connector coating was recommended by Rusty at BR and went on quite easily and has formed a firm rubbery finish on the exposed areas of the board.

Coated Power Distribution Board
In between waiting for the coatings to cure I proceeded to being to attach the BlueESC Control Cables, the Battery Cable, and the Lumen Power Cable to the Electronics Tray End Cap. I will still need to attach the Tether Cable, Power Distribution Board Power Cable, and the Pressure Sensor.

Electronics Tray End Cap Cable Routing

I have also had a chance to communicate with the Electronics Tray over the Fathom-X ROV Side/Topside Interfaces. Using the latest Daily Build of QGC I was able to view the RPi HD Camera and view the ArduSub parameters. I also took the time to update the Pixhawk ArduSub firmware to rc3 which corrected the Pressure Sensor issue where the Pressure Sensor was set to the Firstbaro and not the Secondbaro all of the time. This week I plan to configure the Pixhawk various operating parameters and sensors and prepare for the ROV's first dive in my 38 gallon test tank.
More to come.
Regards,
SSN626B/TCIII

[SSN626B]

Hi All,
I have completed the calibration of the Electronics Tray which included the accelerometers, compass, and battery monitor. I also verified the functionality of the baro 30 external pressure sensor, added the SOS Leak Sensor board and mounted the four Leak Sensor probes on the Tray. Now I am ready to attach the Electronics Tray to the End Cap, but not before testing the integrity of the Cable Tray and Battery WTC cable penetrators and End Cap O ring seals.
To test the WTC cable penetrators and End Cap O ring seals I followed the instructions in the BR BlueROV2 Assembly instructions except that I used a motor driven diaphragm vacuum pump and did not have the Electronics Tray in the main WTC during the vacuum testing. BR recommends pumping both WTCs down to 10 inches of vacuum, wait 15 minutes, and then verify that the vacuum has dropped no more than 1 inch and is 9 inches or greater. I took the vacuum to 22.25 inches and after 15 minutes, I had lost only 0.5 inches of vacuum which I consider to be acceptable given the vacuum test setup.
Now, I will attach the Electronics Tray to the its respective End Cap, make all necessary cable connections to their respective connections in the Tray, and then proceed to tidy up the external wiring, add the Fairings/Buoyancy, and the Ballast, and then prepare for the first dive in my 38 gallon test tank.
More to come.
Regards,
SSN626B/TCIII

[SSN626B]

Hi All,
Finally got the Electronics Tray all cabled up, the buoyancy fairings, and the ballast weights installed on the Frame and a vacuum test of the two WTCs.So I was ready to put the ROV in my 38 gallon test tank. The biggest problem I had prior to being ready to test was getting the Power Cable from the Electronics Tray WTC to the Thruster Power Distribution Board to be watertight. It took about two weeks of experimenting and testing to achieve a waterproof seal.
I charged up the two 3S 5000 mah LiPos that I am running in parallel and stuffed them into the Battery WTC and let the ROV run for a while to heat up the air in the Electronics Tray WTC prior to sealing the vent plug. I then put the ROV into the test tank and added water. When the test tank was 2/3 full the ROV began to float and according to the QGC HUD, the Frame is stable in both pitch and roll.
I then tested the functionality of the Thrusters, Camera Servo, and the Lumen Lights. All of the components worked as expected. It is kind of wild to watch the ROV Frame move sideways (strafing) as I have only been used to three thruster ROV Frames. Even with only the BlueESC T100 Thrusters at 50% drive, the ROV seems pretty powerful.
Pictures below show the finished ROV Frame:

Front View showing RPi Camera and Lumens

Rear View showing BlueESC Thruster Power Distribution Board and temporary Tether

Side View
I believe that this project proves that the BlueESC Thrusters can be used in a BlueROV2 Frame, but it is not the easiest project I have tackled especially getting the Power Distribution Board Power Cable watertight.

I will grab a shot of the ROV in the test tank to show how well balanced the Frame is due to Rusty's (BR) excellent ballasting scheme.

More to come
Regards,
SSN626B/TCIII

[Silver dollar]

Beautifull!

[sthone]

WOW I've been following this build and I have to say it's very professional looking. I can't wait to see it in action.

[SSN626B]

Hi All,
Thanks for the kudos Steve, much appreciated.
Here are a couple of shots of the Conversion BlueROV2 in my 38 gallon test tank:

BlueROV2 Front View

BlueROV2 Side View

Regards,
SSN626B/TCIII