I have been doing a bit more with the rov, I have re-cut the motor/body support out of plastic sheet that I have laying about and I think these are more robust(pic4). I happened to have the landing gear for a helicopter spare so this has been called into service as skids
I have cut the perspex tube longer than I think I will need, once I have figured out how am going to arrange all the components inside I hope I'll be able to shorten it somewhat.
The last couple of pictures show how I will lay out the ESC, the bottom 4 are unidirectional low cost esc from ebay, I am a bit worried about overheating them as there will be no airflow over them so i have sandwiched them between aluminium flat bar to act as heat sink, I cut the heat shrink away from where the esc heat sinks are to give better connect althought i would have added some heat sink compound if i could find where i left it You can see I left a gap between the pairs for cooling, so its arranged as follows,

aluminium flat bar
ESC
aluminium flat bar
air gap
aluminium flat bar
ESC
aluminium flat bar

On top are the bi-directional esc for the depth thrusters. oh the green on the edge is fuel tubing cut and put on the edges of the aluminium flat bar so in doesn't scratch the inside of the perspex tube.
I still have to figure out how am going to pass the mass of motor cables out through the back end cap, thing will get messy i think......

To be continued........(some time lol)

Rob

looking good

that looks great!

ok another drop in the sea of ROV building,
This time I have been working on the camera for my ROV, I wanted pan and tilt but there is not much room in the dome area for this but I've managed,
It has been made from double sided pcb, drawn up it autocad and cut with my mini cnc router.
The pictures show more than words and also a video

ROV camera (0 min 31 sec)

Been doing a bit of work on my bulkhead feed throughs which are needed to take the power from the ESC inside the ROV to the motors outside in the water. I have made them from brass rod, drilled holes in each end which bullet connectors can plug into. The rod has a step turned onto it and threaded at one end. The bulk head will have a hole drilled into it, part way at 8mm then the rest at 5mm, this creates a step inside the bulkhead which matches the step on the brass rod, an o-ring is fitted and when all put together the o-ring is compressed when the nut is tightened which should seal the feedthrough to the bulkhead.
Not very clear so on with the pictures.

All motor feed-through finished, just have to clean up the mess

Still have to decide on how am going to feed the tether through the bulk-head and how many cores I want to use, I had planned to use just two with video over the one wire comms am using, but using four and keeping the video and data separate would be simpler.

Been thinking about how to layout the feedthroughs for the motor in the rear bulkhead, really undecided at the moment so any feedback well come, I've attached a few layout plans,

been a while since i looked at this project and even longer since i looked at the firmware, man its hard to follow assembly programming so its going to be hard to get it tested and running

Hi Rob.
What are you using ??

Originally Posted by robe_uk

been a while since i looked at this project and even longer since i looked at the firmware, man its hard to follow assembly programming so its going to be hard to get it tested and running

mabe I can help ??
Antony

Hi Antony
I use Microchip MPLAB IDE assembly language and I have now the basic control running although I would like to smooth things out but it'll do for now.

I have actually done a bit of work on the ROV 'Yippeee', I have the the feed-thoughs for the motors fitted into the end bulkhead, and the umbilical feed-through fitted.

These pictures show how I used a paper template stuck onto the bulkhead for drilling. A 5mm hole is drilled all the way through then the hole is drilled to 8mm the a depth of about 10mm, this creates a step for the oring on the pin to seat onto.
The feedthrough pin complete with oring is inserted and the nut then pulls it tight creating a seal.

Now for the umbilical which is part that has had me worrying about how to do it. I had planned to just use 2 wires(1 pair) and have data and video sent other each other but keeping it simple I went with 4 core, 2 for data, 2 for video.

I made the feed-through removable so that I can upgrade if needed without having to scrap the whole end bulkhead.

The pictures show how I have made it up.

next step is the assemble the body without electronics and take it to a pier the depth test it to check for leaks, at high water the depth would be about 5 or 8 meters, or i could take it with me on my next dive and test it to a much greater depth, but I original designed it for use around the pier with the kids and do not have regular access to deep water so pier test probably would do.

Hi Rob.
Go ask a scuba diving club to take it down with them. I have dived with your local club..nice bunch.
Tip cover inside with good quality talc just before testing as this will show moisture were we cannot see it.
The build looks good .
Regards Antony

Originally Posted by hargard

Hi Rob.
Go ask a scuba diving club to take it down with them. I have dived with your local club..nice bunch.
Tip cover inside with good quality talc just before testing as this will show moisture were we cannot see it.
The build looks good .
Regards Antony

Hi Antony
Good tip with the talc must remember that. There are a couple of dive clubs here in Derry, City of Derry SAC and Maiden city SAC which I dive with so I can take it down myself . I'll be working on internal layout next until I get a chance to give the body a good test. But I don't see me needing to use this rov at any great depth, that'll be for v2

Rob

Heres a question, can i use the same type of feedthoughs that i am using for the motors for lights? ie exposed the water, or would they have to be sealed?