Very pretty stuff. I particularly recommend Ken Shirriff’s Reverse-engineering the mechanical Bendix Central Air Data Computer:

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He goes into detail about how non-linear equations are implemented using shaped cam gears (and how such functions can be difference-encoded against linear forms). It’s insane.

And because it’s analog, there is no quantisation, rounding errors, floating point errors.

Eh, I’d say that runout and stiction are their own demons with potentially more bias than those error types :) Not to mention temperature sensitivity – hot days will give different answers to the equations.