Vertical Thruster Shroud and Guard


#1

As I made some progress with assembling the ROV, I found a lack of documentation regarding the glueing of the thruster shrouds, so I ran into two issues:

1. I glued the vertical thruster guard on top of the top plate which now makes it very difficult to insert the vertical thruster when it is mounted to the motor. I think the right way is to glue the guard only to the thruster shroud (and not to the top plate), so that that both can be removed together when mounting/unmounting the prop and the motor?

2. When I put the acrylic tube into place at the ROV's chassis, I noticed that it collides with the vertical thruster shroud. First I thought that I made a mistake in glueing the structure, but when I looked at the Autodesk Inventor files (https://github.com/OpenROV/openrov-hardware), it seems that this is by design. So the best would be to sand the thruster shroud down on one side until the acrylic tube fits correctly?



#2

Yes, Stefan, this is a great point. By just gluing the guard to the shroud (and not the structure), you can remove it to attach the motor. It's such a tight fit that it shouldn't cause any problems. Ours does sit a bit higher than the top plate to avoid the electronics tube.

I'll add this to the wiki. Where in the wiki did you run into this issue? I'd like to make sure we include this information in natural place in the process.

-David


#3

David,

there isn’t any documentation about attaching the thruster shrouds, the guard, the motors, the props, and the acrylic tube to the structure in the wiki yet (at least I could not find it). So it would be great If you could add one or two pages with photos or videos to it.

It would also be helpful to include in the documentation that the wires coming from the motors an the battery tubes go from the starboard to the port side of the ROV before entering the acrylic tube (I could se this in an OpenROV demonstration video on Youtube, but it would be helpful to include this in the wiki as well (mabe some photos of the fully wired ROV).

Kind regards, Stefan


#4

On it. Working on this today.


#5

Stefan,

Great points on all accounts. Thank you for pointing those out to us and sorry for the inconvenience. Regarding the vertical thruster shroued collision with the main electronics tube- I think sanding the tube slightly like you describe is probably the best option. From my builds, the two usually end up clearing each-other by a small margin, but perhaps the tube you got was a millimeter or so longer then that. You're right that they do seem to collide in CAD. Perhaps I'll call out a slightly shorter shroud length in the next revision. I can't think of a very elegant way to work around the vertical thruster guard being glued in place, but I'll try to think of a way for you to place and remove the motor more easily with your configuration.

Thanks again for the input on all of this- we can really use the help!

Eric


#6

David and Eric,

thanks a lot. Let me know if I can help you out in any way.

-Stefan


#7

Out of curiousity, why is the guard designed as a separate piece? Why not just cut it into the shell?


#8

If you cut it into the shell, then you'd have to remove the shell to remove or service the vertical propeller. It could be done, but would be very inconvenient. You should be removing the props after every dive to be able to rinse and dry the motors.

-W