Re: AUV Questions

[Coast Guard Kiteman <exfloridians@ecsu.campus.mci.net>]

At 03:58 AM 5/14/1998 GMT, you wrote:

>On Wed, 13 May 1998 18:21:32 -0400 (EDT), Coast Guard Kiteman
><exfloridians@ecsu.campus.mci.net> wrote:
>>         "AUV"?  ["Autonamous Underwater Vehicle"?]


>Yes. Basically a robot submarine, with a very complicated computer "brain".
>The software running an AUV is considerably more complex than what is
>required for a land-based robot, for a number of reasons.


        I've seen them on television, but had never heard "AUV" before.  Or
I just wasn't paying attention enough. <g>


>>         Jon, are most AUV's being designed or built right now straight
>> battery powered?


>Most are battery powered, but there are exceptions. I have seen one AUV
>that uses a closed-loop diesel engine, and another that uses a hydrogen
>fuel cell.
>
>The real problem with the fuel cell is getting rid of the water it
>produces. For shallow water (<1000 feet), it's not a big deal, but at
>20,000 feet, the pressure outside makes venting the hull of anything
>impossible.
>
>I don't suspect you'll ever see a small fuel-cell powered deep-diving sub,
>because of that. What some people are looking at for long-term use is
>having a "mother ship" station on the bottom, with a big cable carrying
>power and data to the surface. The AUVs would periodically dock at the
>mother ship to recharge their batteries and download data, and upload any
>new instructions/missions.


        OH?  How much water exactly does a fuel cell produce?  I didn't
realize it was that much.  I mean, I know they do make water, and that's
a source for water on the space shuttle.  But it's enough to be a problem
on a small sub?