Comment by madaxe_again

10 years ago

This article makes it out like gunning computers as a whole were some kind of new and revolutionary technology - while it's a feat of miniaturisation and lovely engineering, some of the earliest computers (either mechanical or electromechanical) were specifically for gunnery. Firing an artillery or naval shell 20 miles requires some pretty complex (well, if you're in a firefight - it's not that hard but it's not "oh let me think about that a moment") maths to compensate for aerodynamic effects, spin, and the Coriolis effect.

https://en.wikipedia.org/wiki/Rangekeeper has a decent summary of the development of this tech.

Speaking of targeting computers, one of my favorite videos on YouTube is a training film describing the theory of operation behind a purely mechanical fire control computer by the US Navy circa 1953 https://youtu.be/s1i-dnAH9Y4

  • I love that film, but it's kind of weird that it doesn't mention what's probably the most important invention that makes this type of computer possible: The torque amplifier.

    All the devices shown suffer power losses between input and output, some of them severe. A torque amplifier has two shafts that are 1:1 geared for speed but the output shaft has extra power taken from a third supply shaft, like the supply to a logic gate that lets it drive more output power than it draws from its inputs.

    https://en.wikipedia.org/wiki/Torque_amplifier

  • Thank you for that. I just watched a few minutes, but already, watching a cam compute a reciprocal is by far the most interesting thing I've seen all week.

    Analog computers were basically voodoo to me before this. Looking forward to watching the rest!

  • Thanks...just goes to show how brilliant some of our pre-digital forbears were. I still give more props to old school television engineers to present day ones. The laws of physics are far more unforgiving than the laws of a compiler.

If you ever find yourself near Fall River, Massachusetts, you can tour or just walk around the battleship USS Massachusetts.

One of the (many) really cool things on the ship was that you can climb into the 14" gun turret and play with an actual mechanical computer for computing range & elevation.