U.S. NAVY BASIC MECHANISMS OF FIRE CONTROL COMPUTERS MECHANICAL COMPUTER INSTRUCTIONAL FILM 27794

Two gems (among many)... Periscope Films (on YouTube): [LINK] Digitized 40-60s era reels. It still amazes me how effectively they presented complex topics then. E.g. mechanical naval gunnery computers: [VIDEO] And this on-the-ground movie on the Columbia student occupation in 1968: [LINK]

You might like this video about the US Navy fire control computer. Mechanical yet also programmable. Eg with cam-based calculation modules like 1/x or differential gearings to perform addition : [VIDEO]

If you want more information on how you can do computation with mechanical systems, try this video: U.S. NAVY BASIC MECHANISMS OF FIRE CONTROL COMPUTERS MECHANICAL COMPUTER INSTRUCTIONAL FILM 27794 [VIDEO]

This could use a lot more visual aids. Here's a film that goes over a lot of the basics: "BASIC MECHANISMS IN FIRE CONTROL COMPUTERS" [1]. It's a 1953 US Navy instructional film explaining how mechanical fire control computers worked. These machines took inputs giving the speed and direction the ship was traveling, the speed and direction the target was moving, the distance and direction to the target, the wind speed and direction, and other factors, and computed how to aim the guns to shell the target. [1] [VIDEO]

I went a bit further back when I saw "mechanical programming" and thought of this video. [VIDEO] Mechanical analog computing FTW!

If you enjoy this, don't miss the video lecture on World War 2-era mechanical fire control computers by the U.S. Navy. I learned you can do a lot of computations with gears and shafts. [VIDEO]

So I've known about slide-rules for a while. What I didn't realize was that the mechanical principles of slide-rules were applied to fire-control computers on WW2-era Battleships. [LINK] These computers had slide-rule like cylinders that would rotate. As you aimed the gun sights "at" a target, the gun's coordinates were being mapped to a cylinder, which would move the gun a different direction (you have to aim the gun "higher" the further away the target is, to account for gravity "drooping" the bullet). In effect; the weirdly shaped cylinder inside the fire-control computer is a pre-computed solution that maps x/y coordinate inputs to a z-coordinate output (where "z" would be fed into the gun's raw aiming system). The different parameters of the gun were programmed in with gears and cranks, moving the cylinder around physically. For more details, see: [VIDEO] Its a 20-minute video. The cylinder mechanism (of 2x inputs mapped to 1x output) is specifically talked about here: [VIDEO] . Carefully crafted cylinders could be any pre-computed 2-input / 1-output function. --------- Mechanical computers are fun. Slide rules are but the simplest kind. People were using more complicated "mechanical computers" for very serious combat / rangefinding / etc. systems just a few decades ago, before the advent of modern digital computers.

The US Navy had this great video on principles of mechanical computers. Using cams and gears to compute functions. [VIDEO]