A minor Adventure in Vintage Computing

[Carlos Murillo-Sanchez]

Brent Hilpert wrote:
>  I don't know a lot about Foxboro, I believe they were a spin-off or startup
> company in the 60s that were early entrants into the (then small and
> state-of-the-art) area of computer-based real-time process-control for large
> industrial plants. They are one of those names you don't run across much unless
> you run in those circles.
>  Additional comments about Foxboro and their systems from those who may know
> more appreciated.

Foxboro was a british industrial instruments company with a very long
history.  Among other achievements, they were the first to offer a pneumatic
process controller with proportional+integral action (pneumatic controllers
in those days were on/off or at most proportional).  It was called
the "Stabilog",  and it was introduced in 1930; it followed the introduction
of the negative-feedback pneumatic amplifier designed by Clesson E. Mason
(also at Foxboro) in 1929 to linearize the action of pneumatic-actuated
flow-control valves.  This started the era of pneumatic-based analog
computation in process control equipment (on topic).  I remember
seeing a brochure from those days, trying to lure control practitioners
to install "modern pneumatic process control equipment: imagine your
plant with pneumatic instrumentation so you can control it with signals 
that move at the speed of sound" :-) .  This may seem funny nowadays,
but it was really this kind of technology that allowed the feasibility
of _really big_ refineries, fertilizer plants and so on.  Electronic
controls in industrial settings were still a few decades from commercial 
success.

The first instance of closed-loop control using a digital computer
in an industrial setting supposedly happened at a Texaco refinery
in Port Arthur in March 15, 1959, using an RW-300 computer
(does anybode have a good reference on this?).

carlos.

-- 
Carlos E. Murillo-Sanchez
Universidad Autonoma de Manizales, Manizales, Colombia