More water tests today. Chasing leaks. Having a bear of a time getting these epoxy penetrators to seal. Not sure what is going on but maybe I didn’t clean the penetrator or motor cables enough? Have a full wetlink penetrator set coming next week so hopefully I won’t have to worry about it any more. Found some Walmart boogie boards for temporary buoyancy. Really digging the sleek look but curious to how deep they will go. Currently 7lbs positively buoyant so currently debating removing foam or adding weight (maybe both?). Heading to a local lake in Kentucky in two weeks which has allegedly a submerged town. Pretty excited to see if we can find anything.
Very cool @buckarooooo -
We similarly struggled with potted penetrators, and generally don’t recommend them - we’ve only seen school teams that work at shallow depths for short time periods, and value the flexibility of supporting multiple cable sizes with the same part, continue to find success with them. The WetLink Penetrators you have coming should be the silver bullet for your leaks!
Definitely post what you find in that lake to our Adventure Log forum category!
Wetlinks are installed. Doing another leak test as we speak. Very close to neutrally buoyant. In the down time waiting for parts, I re-designed and printed a new bracket for the electronics and battery housings.
Getting closer!
First powered water tests are done! The night before we leave to go on our trip lol. Fought with the camera for a LONG time. My usb camera only support MJPG or YUY2. I could get the feed to show up for a second then immediately lost it. Thankfully a local best buy had a cheap 1080p h.264 camera that has worked perfectly so far. Printed a quick mount for it and am pretty happy with the results. Overall impressions are the unit is painfully underpowered. It will do for now but monetary constrictions make it a tough problem to solve (I do have some ideas though.). Please enjoy the pics/test video.
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Quick-ish update 
. Ordered some Samsung Q30 cells to rebuild the battery. My original battery consisted of used laptop cells which were already really old 3 years ago when I built it. These new cells average around 3300mAh which should put me around 42Ah total capacity at 11.1v. This new battery will utilize the same HX-3S-FL25A balance/charge board like the one before.
Also been working on my own auto pilot board based on the new RP2350 MCU. This has recently lead me down the rabbit hole of inertial navigation and I found some interesting research papers on how IMU arrays can significantly cut down on sensor noise. I put together a quick PCB for some MPU6050 breakout boards and a Raspberry Pi Pico W for testing. Funny enough these 6050 breakout boards were cheaper than purchasing the individual sensors and supporting components. I also wrote a TCP server that will let me 3D plot Inertial Position with Matplotlib. If this proves successful I hope to build out a much smaller IMU array for the ROV for the sake of alternative depth sensing, position lock, and knowing location in reference to home.
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