Deep ROV Files That I used


#1

I have meant to post a howto for a long time now, but always it gets put off.

Here are the files:
https://drive.google.com/folderview?id=0B_7o6yPNVfY6c25xbC1qV2ZfWm8&usp=sharing

Here is a link to the files I used for ChubbyIII(DTP). I widened the chassis and the shell. To make this work for 2.8 or any version, you will need to widen the chassis. 12mm is the extra I added IIRC. The extra space allows you to have 1/2" (12.5 mm) endcaps fit.

For the thicker endcaps, I used a drill press to drill holes into the side and again down from one side to push the wires through for potting.

The battery tubes are also thicker. I used 1/8". The batter tube endcaps are also thicker. I am not sure they need to be, but they are small and you can often cut them from scrap 1/4" any way.

This is a picture of the potting holes drilled into the side of the endcap. Doing it this way allows you to save space and still have a strong solid 1/2" endcap. Hooray!

I just typed this up quickly and so obviously I have a lot of gaps to fill. If you have questions, please ask them.


#2

On the “1 point 5 mm sheet” the only parts you need are the rings. those are attached, with acrylic glue and or epoxy, to the edge of the e-tube. Then you use a face seal in addition to the standard seal.


#3

Thanks Darcy

As a matter of interest what the deepest you had it down to? Who’s leading the deepest dive for a modified unit you or @Walt_Holm?:+1:


#4

Walt has the deepest dive at I think 285 meters. My deepest was, in testing, about 265 meters. My deepest in an actual expedition is 208 meters. The reason I have not pushed it, is that getting to a deep part of the ocean (my preference) and still being in control of your vessel is tricky. I don’t have station keeping on my science vessel, the ‘Bouncy Castle’ and, due to currents and wind, I therefore have to anchor my self to the bottom. 200 -300 meters is not a depth that you can properly anchor. The rule of thumb is 3 to 7 X the depth (and higher depending on conditions). That makes for 1 KM or more of anchor line. :smiley:

You don’t need to anchor for testing of course. Just find a nice deep area and float along with the current. :smiley:

I did try a mooring buoy at 100 m. But it disappeared.


#5


#6

Hey Darcy:

I should post some photos showing the current rebuild of Chubby, now at revision 4.5. Zack turned some endcap inner pieces out of PVC for me, which I bonded to acrylic outer pieces to make sort of a composite end cap. I’ve got a new tether reel with 420m of tether on it.

I was hoping to get out to Tahoe last week to test the new endcaps and test homeplug communications over 400m of tether, but the vehicle wasn’t ready so it didn’t happen. The PVC endcaps are significantly denser than acrylic, so they threw off the balance of the vehicle- I’ve got to reposition the battery tubes and add a little more flotation to make it work properly.

-W


#7

Walt,

I would really like to see those photos.
Do you have a slip ring on your reel? I was going to make you one, but my order (from eBay) never arrived. :D.


#8

Hi Darcy:

Yes, I’m using a slip ring that I got from Adafruit, rather that trying to make the connection via WiFi. I’m also using a heavy-duty hose reel from CoxReels that is significantly beefier than the orange plastic reel that people have used for shorter tethers.

My current tether setup deserves a series of posts on its own, as its specifically set up to be used for deep-water work. Brian Grau has been taking pictures of it for me as I’ve gone along, but I wasn’t going to post anything until it’s been to Tahoe and shown to work at >300m depths.

-W


#9

I’m rooting for the Canuck!

O


#10

First off Thanks again to Darcy for sharing and congrats :clap: to Walt for leading the table :raised_hands: (hope a few people take up the challenge and chase your lead down)

I would be interested in some of your real world experiences with the unit at depth

Over here we can get a fair bit of current so would like to know how this goes with the ROV as the depths get really interesting

(PS and I wont say who has a couple of machined 4" stainless pressure pipes suitable to mmmmm about near as 1km sitting at home just waiting for work to quite down to start a longer project)

mmmm sitting in 400m just off my door step


#11

Scott,

Is the current near the surface? or at the depth you will be operating?


#12

Normally almost the whole way down

Often (and I wouldn’t deploy a ROV in it) we can throw a shot line (say 6mm rope and then 2 off 20L drums as floats) in 100m and they will be pulled under

I would only be cherry picking best days for any deep water stuff