rg@msel.unh.edu (Roger Gonzalez) (06/24/91)
Now that we will be running VxWorks on our AUV (autonomous underwater
vehicle) we need some way to have a on-deck tether for mission setup,
data offloading, and self-tests. When we were running pSOS and using
serial lines, we used a 12(?) wire fat tether with serial lines 2/3/7
going to each of the on board computers. Presumably all we need now
is an ethernet connection going into the hull. Because it is in the
water, I thought it would be nice if we didn't have to constantly
worry about capping the through-hull connector when we remove the
tether, and was thus wondering about fiber optics. Is there any sort
of pressure/watertight dooflotchit that we can use to run fiber out
through the hull? (What sort of power do fiber tranceivers need anyway?)
Any other alternatives for running ethernet out of something that you
dip in the drink? (Opening up the pressure tubes to connect is not an
option- we've had too many close calls with folding or crimping
O-rings and watching the AUV slowly sink rather than float on the
surface)
Thanks,
Roger
--
Geek joke: Why did the plane taking off from Warsaw crash?
Too many poles in the right half of the plane.
rg@[msel|kepler].unh.edu | UNH Marine Systems Engineering Laboratory
| Durham, NH 03824-3525doughe@bamboo.TEKTRONIX.COM (Douglas E Helbling;627-2621;46-176;;) (06/25/91)
>From: rg@msel.unh.edu (Roger Gonzalez) .... >Any other alternatives for running ethernet out of something that you >dip in the drink? (Opening up the pressure tubes to connect is not an >option- we've had too many close calls with folding or crimping >O-rings and watching the AUV slowly sink rather than float on the >surface) This looks like a good application for optical fiber. You could install some fairly off-the-shelf fiber transceivers ($300-600ea) at the host (surface control) end as well as internal to your subsurface machine, and use some variation of a standard fiber male-to-male coupler to bridge the signal through the hull. That way, a complete cable severance would still not render the machine open to seawater. Doug Helbling