Re: [PSUBS-MAILIST] Water depth sensing?

["steve" <steve@kobol.worldonline.co.uk>]

Hi All

Unfortunately there is still no sign of the Kitteridge book but i expect the
US / UK post offices are taking their time.  maybe they read everything they
send???

As part of my ROV project i want to look at a way of measuring the depth of
my vehicle.  I am toying with a Basic stamp 2 at the moment and wondered if
anyone had any ideas for a small (i.e. cheap) sensor that i could use for
this purpose.
My design spec will only need to measure down to 20m in fresh or sea water.

anybody got any useful ideas and know where i could source one?

Best Regards

Steve Bosworth
UK
----- Original Message -----
From: "Dewey Mason" <drmason2001@yahoo.com>
To: <personal_submersibles@psubs.org>
Sent: Friday, February 20, 2004 1:50 AM
Subject: Re: [PSUBS-MAILIST] test of CO2 safety hardware - any volunteers?


> If tested well, and found to work, this could serve as
> a backup unit to a commercial device, or even just as
> a novelty, but I agree in should be looked into. My 2
> cents.
>
> Dewey
> --- Pierre Poulin <pipo305@hotmail.com> wrote:
> > Erik,
> >
> > I will try it. I just need some time. I will try it
> > mainly for curiousity
> > and discution. I think that's all this group is all
> > about! To get new things
> > developed and discussed.
> >
> > Pierre Poulin
> >
> >
> >
> > >From: Erik Muller <emuller@naic.edu>
> > >Reply-To: personal_submersibles@psubs.org
> > >To: personal_submersibles@psubs.org
> > >Subject: Re: [PSUBS-MAILIST] test of CO2 safety
> > hardware - any volunteers?
> > >Date: Wed, 18 Feb 2004 12:23:52 -0400
> > >
> > >Gail,
> > >Many of the points you made are true. Let me
> > address them one at a time:
> > >
> > > >I'm wondering how accurate and useful a device
> > like the one you describe
> > >would be.
> > >Indeed, as am I. This is why I am calling for
> > people with air-tight hulls
> > >to test the system. I am not suggesting that it be
> > implemented on anyones
> > >machine before testing its efficiency and it is
> > developed.
> > >
> > > >With reliable professionally-made devices being
> > available, why would you
> > >want to entrust something as important as life
> > support to a $0.50
> > >expedient?
> > >That is true: you need to fold in the reliability
> > of your equipment is to
> > >the decisions you make in piloting and using your
> > craft. However, to take
> > >this question to the (unreasonable) extreme: why
> > would you build your own
> > >submarine when you can buy a perfectly operational
> > one, brand-new for a few
> > >hundred thousand or million? The fun is in the
> > manufacture and learning how
> > >it all works. However, care needs to be taken when
> > using new systems in
> > >that they are tested properly. Perhaps the 50c
> > device works well enough as
> > >a first order indicator. I dont know. I think it is
> > worth finding out. I DO
> > >know that it tests positive for a single breath,
> > which has more that enough
> > >oxygen remaining in it to be comfortable. If
> > anything, I think this will be
> > >an overly-conservative indicator. I can cite the
> > age-old 'NASA vs USSR -
> > >high tech gravity-proof-pen vs  ordinary pencil'
> > example as a great case
> > >where cheaper is better. This might turn out to be
> > one such case.
> > >
> > > >From what I've learned, CO2 levels are taken care
> > of by the scrubber, and
> > >it's pretty easy to verify whether or not that's
> > working.  So this home
> > >made CO2 sensing device doesn't sound necessary.
> > >
> > >Sure, but some people dont have a scrubber in your
> > machine. Others have
> > >different systems to help reduce CO2 pp. Scrubbers
> > are not part of
> > >everyones hardware. I have not planned for one
> > since my dives will be
> > >short.
> > >
> > > >Speaking for myself, I think I'd prefer the
> > professional instrument.
> > >Thats fine. Then this system is not for you. Some
> > people dont have the
> > >money, or want to try to make it all from the
> > ground up (i.e. some people
> > >like to grow their own for the fun of it). Im not
> > insisting that this
> > >system be immediatly implemented by all. Just that
> > it is a system that
> > >MIGHT be useful to SOME people, and is worth
> > testing. Nothing more. If
> > >tests show  that it is unusable, then we have
> > learned something. If tests
> > >show that it IS useable, then we have also learned
> > something. Its a win-win
> > >world in this case.
> > >
> > >There is a commercial in australia which says: 'you
> > will never know if you
> > >never go'. If its not tested, we will never know if
> > it is useable, or not.
> > >People have been objecting to my suggested
> > technique for about a week, yet
> > >no-one has tested it. I would really prefer that
> > people object with numbers
> > >or solid data, rather than opinions. The proof is
> > in the pudding. We grow
> > >by testing and learning. <insert other assorted
> > feel-good anthropic cliches
> > >here>.
> > >
> > >Anyhow. thats enough from me.
> > >EM.
> > >
> > >
> >
> >
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>
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