Path: utzoo!utgpu!watserv1!watmath!att!rutgers!usc!zaphod.mps.ohio-state.edu!sdd.hp.com!hplabs!otter.hpl.hp.com!otter!tgg
From: tgg@otter.hpl.hp.com (Tom Gardner)
Newsgroups: comp.arch
Subject: Re: Magnetic amplifiers? [was Re: Mercury delay lines]
Message-ID: <780017@otter.hpl.hp.com>
Date: 16 Jul 90 11:19:27 GMT
References: <2072@mindlink.UUCP>
Organization: Hewlett-Packard Laboratories, Bristol, UK.
Lines: 17

|The last company
|to push fluidics for computation was Corning.  As recently as the mid-70's,
|they had a line of logic modules you could use to build small all-fluidic
|digital circuits.

Hydraulic logic has definite advantages in hostile environments: 
 - no electricity required, so reduced danger of explosion where flammable
   gases are present
 - robust
 - noise immune, so long as the pressure in the power source is in the 
   range 2000 - 4000 psi the logic will continue to work

I first came across hydraulic logic in ~1983 where it was being used to 
control the operation of unmanned offshore oil platforms. We concluded that
(at that time) to replace the hydraulic logic with a uP would involve
considerable time and expense, and that there would be no corresponding 
benefits...