Mechanical Computer (All Parts) - Basic Mechanisms In Fire Control Computers

> analog computers don't generally compute by operating on symbols. For example see the classic video on fire control computers ▶ this video > OP's specific phrasing is that they "map symbols to symbols". Analog computers don't do that. Some can, but that's not their definition. How is that not symbolic? Fundamentally that kind of computer maps the positions of some rods or gears or what have you to the positions of some other rods or gears or what have you, and the first rods or gears are symbolising motion or elevation or what have you and the final one is symbolising barrel angle or what have you. (And sure, you might physically connect the final gear directly to the actual gun barrel, but that's not the part that's computation; the computation is the part happening with the little gears and rods in the middle, and they have symbolic meanings).

analog computers don't generally compute by operating on symbols. For example see the classic video on fire control computers ▶ this video OP's specific phrasing is that they "map symbols to symbols". Analog computers don't do that. Some can, but that's not their definition. Turing machines et al. are a model of computation in mathematics. Humans do math by operating on symbols, so that's why that model operates on symbols. It's not an inherent part of the definition.

I just smile hearing the term "Millihertz Computer". I'd love it if building and designing mechanical and analog computers grew as a hobby/educational activity as I find them both fascinating and somehow satisfying. Also, this 1950s Naval Training film explaining the fundamentals of how mechanical fire control computers work to solve complex problems is excellent. ▶ this video

I do hope watchmakers start to integrate "computational" (instead of temporal) complications into their watches, like a mechanical turing machine or other tiny mechanical computers or calculators which I believe have never been constructed this small. Inspiration: Wooden Turing Machine: link Curta Calculator: link Zuse Z1 Computer: link Maybe also analog ones!: ▶ this video

Everyone reading this right now needs to check out this 1950s naval training video on the mechanical fire control computers of battleships: ▶ this video For fun, before you watch, think for yourself how you'd implement addition, multiplication, squaring, etc. with only gears and other mechanisms.

The engineering knowledge that went into the WWII fire control computers was clearly a form of programming. You will also notice the words "computer", "input", and "output" are used without needing to be explained. ▶ this video

Yes, these are awesome. There is another one of these old films about them which is a great explainer: ▶ this video

If you’re interested in some of the individual components, there’s a great 1950’s US Navy training film on the individual components of analog fire control computers here: ▶ this video The ideas are the same, but the technology is about a decade earlier than the CADC, so everything is noticeably more primitive.

Over the years we have evolved the meaning of computer from something that calculates or reckons to a electronic device that runs software. In reality any black box that has a one-to-one relationship between inputs and outputs can be considered a computer. It might be easier to think of mechanical computers, such as the WW2 fire control computers aboard Navy Ships[0] or more famously the Antikythera mechanism[1]. These are fixed devices, they compute values from inputs. The "program" is stored in the gears camshafts and differentials and ratios between them. Similarly, fixed digital computers such as the Nimatron have their operations stored in relays and digital logic. These sorts of computers don't have a list of instructions. They just have schematics, inputs going through electronic circuits that wind up at outputs. You can do a lot of calculating with just simple logic gates. [0] - ▶ this video [1] - link

Mechanical computers for fire control where the standard solution until very recently. Here's a very interesting video about them: ▶ this video

A differential is an adder.[1] This is a differential hooked up as a doubler. Mechanical analog computers, especially gun predictors, had lots of setups like that. [1] ▶ this video

Apparently the Navy also used mechanical 'computers' on old battleships to calculate firing solutions. Sailors would adjust cranks and shafts to set the input values, and those inputs were connected to cams which were machined in the shape of solutions to the equations that needed to be solved. You can watch an old training video about it from the '50s: ▶ this video

I did not see any link to the full training video[0] the clips in this article were taken from. I highly recommend it. It's a fascinating trip into engineering, computing, and the past. [0] ▶ this video

The whole training film on mechanical computers, for navy mechanics I believe: ▶ this video It illustrates the problems and solutions near perfectly, and I've watched it way too many times.

One of my favourites is this 1953 explanation of the workings of mechanical analog computers used by the US Navy: ▶ this video

I recommend watching this video if you're interested in learning about multivariate analysis using mechanical computers. It's very approachable and informative. ▶ this video

▶ this video This is an old military instructional video about fire (artillery) control computers, explaining the mechanical aspects of how they work. It's beautiful in its elegance! I have watched it on multiple occasions just for the sheer beauty of the mechanisms involved. And, yes, of course I'm a nerd!

This old US Navy training film on mechanical fire control calculators (called "computers" back then, used to calculate firing solutions on warships) is pretty fascinating: ▶ this video

Interestingly, several months ago I came across the following 1953 training video dealing with this same subject. ▶ this video

Obligatory link to youtube video of a 1950s training video on the mechanical fire control computers (which I stole from HN last time this sort of topic came up): ▶ this video edit: This video is the same footage featured throughout the article, in fact.