Re: Re: [PSUBS-MAILIST] hull test

[irox <irox@ix.netcom.com>]

The camcorder idea might be a bit problematic, depending how deep your sub
is being tested.  The longer your cable, the higher the resistance, the worse the signal
quality will be when it reaches the surface.  Of course it's pretty straight forward to
test, just layout the cable and dry land and what you can see.

RS432 (slow) or fiber-optic (fast) would work over large distances, but this would
increase costs (the later more than the former) and complexity.

Ian.

-----Original Message-----
From: Paul Kreemer <paulkreemer@gmail.com>
Sent: Oct 27, 2005 3:43 PM
To: personal_submersibles@psubs.org
Subject: Re: Re: [PSUBS-MAILIST] hull test

Rick, there you go, some good practical methods. Put a plain old camcorder
onboard. My idea with a video cable running to the surface was way too
complicated. And pessimistic. You want to believe that you'll get the
camera, and sub, back fairly dry.

Come to think of it, I have a JVC miniDV camera that I would love to consign
to a deep watery grave... Or use in an ROV and not worry about flooding.


Paul
Sub-Log.com
Seattle, WA

On 10/27/05, Alec Smyth <Alec.Smyth@compuware.com> wrote:
>
> If I recall correctly, Piccard tested his bathyscaphe by sending it down
> unmanned with a simple clock mechanism to release ballast. In that case, it
> was done untethered in the open ocean and the sub had virtually no depth
> limit, but I can see doing a test like that with Euronaut if you first
> tethered a line between an anchor and a buoy, and sent the sub up and down
> that so as to have more control over where it surfaced at the end of the
> test.
>  Alec
>
>  -----Original Message-----
> *From:* Dan H. [mailto:jmachine@adelphia.net]
> *Sent:* Wednesday, October 26, 2005 10:30 PM
> *To:* personal_submersibles@psubs.org
> *Subject:* Re: Re: [PSUBS-MAILIST] hull test
>
> Bill, Paul,
>  I don't think microwaves are used in underwater communication, but I'm
> not positive. For local communicating acoustic equipment is used. It is like
> radio communication but instead of an electrical radio frequency carrier, it
> uses a high frequency sound wave carrier. Mechanical not electrical, or
> sound wave not electrical wave,
>  For a deep water test, if I ever had to do another, I'd use a line for
> safety and to control decent, but also a simple two wire cable connected to
> a magnetic drop weight system. Something simple, controlled with a dry cell
> in a plastic bag or something as simple as that. No need to get fancy but a
> magnetic release with actual wires to the surface would be best.
>  In large subs they do usually test manned since a leak, or anything that
> is fixable, is dealt with as the test is in progress. Also I remember
> reading somewhere that strain gauges are placed in critical parts on the
> hull to monitor its performance. These need to be tended to and monitored.
> They just pilot it down and watch to see what is happening.
>  Dan H.
>
> ----- Original Message -----
> *From:* Paul Kreemer <paulkreemer@gmail.com>
> *To:* personal_submersibles@psubs.org
> *Sent:* Wednesday, October 26, 2005 4:39 PM
> *Subject:* [Norton AntiSpam] Re: [PSUBS-MAILIST] hull test
>
> Boy I like Bill's idea of remote control of a few key systems. Why not
> attach an umbilical for ballast control, leak detectors and maybe an
> internal camera? One downside of a wire would be coming up with the 300-1000
> feet of cable needed. But you'd have, in effect, a super-size ROV with
> optional human cargo. ;-)
>
> Paul
>
> On 10/26/05, Akins <lakins1@tampabay.rr.com> wrote:
> >
> > Your below post got me to wondering Dan.
> >  Since we use microwave transmissions for underwater communications, why
> > couldn't microwave transmissions
> >  be used to activate a remote control in a sub the size of Carsten's so
> > that a test line would only be there for making
> >  sure the sub did not drift away and for a secondary backup. Would the
> > microwave transmissions go thru the hull and
> >  the remote could be rigged to activate the ballast pumps so the sub
> > could surface after the test depth and time were reached?
> >  Would this be feasible or practical?
> >  Bill.
> >
> > ----- Original Message -----
> > *From:* Dan H. <jmachine@adelphia.net>
> > *To:* personal_submersibles@psubs.org
> > *Sent:* Wednesday, October 26, 2005 8:12 AM
> > *Subject:* Re: [PSUBS-MAILIST] hull test
> >
> > Silky,
> >
> > A sub hull is a lot of money and work to loose if you lower it to the
> > bottom
> > for a test on a line, with no person in it, but it's the safest way to
> > test
> > a personal sub. Of course testing in a pressure chamber would be even
> > better but most small sub builders don't have or can't afford this
> > luxury.
> > Even with the risk of loosing the sub because of a simple line
> > malfunction,
> > a deep water test of the hull should be done unmanned. After all, it's a
> >
> > test to see if you'll be safe diving in it.
> >
> > A sub the size of Carsten's is not in this category. I can only imagine
> > the
> > feeling in Carstan's gut when he does his tests, manning it himself. I
> > have
> > a lot of faith is the calculating skills of a man that can design and
> > build
> > such a project and I'm sure he's pretty confident he will have no
> > problems
> > he can't solve as he goes, but we all know there is considerable risk
> > involved.
> >
> > P-subs should only be test proven unmanned!
> > Dan H.
> > ----- Original Message -----
> >
> >
>




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