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From: tgg@otter.hpl.hp.com (Tom Gardner)
Newsgroups: comp.arch
Subject: Re: Pneumatic computers (yes, air-pressure powered)
Message-ID: <78170002@otter.hpl.hp.com>
Date: 28 May 91 08:01:48 GMT
References: <1991May24.231620.15367@digi.lonestar.org>
Organization: Hewlett-Packard Laboratories, Bristol, UK.
Lines: 10

About 8 years ago I undertook a feasibility study to determine whether
fluidic/hydraulic logic should be replace by microprocessors in a certain
application area. The conclusion: hydraulic logic was better.

The area was sequencing interlocks for the underwater gas/oil valves on
unmanned offshore oil platforms.

Gory technical details: running pressure was 2000-4000psi. AND gates cost
$60 each. Simple flip-flops were available.