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by dchristian 23 days ago
No, the bicycle is unstable. PID doesn't work well there.

In addition, it is controlling a coupled 3D system (which is unstable). This is much more than 3 PID controllers.
4 comments
taneq 23 days ago
PID works fine if you parametrise it right, which is what this paper does. Consider the variety of inverted pendulums etc. that are used as as examples to teach PID control.
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literalAardvark 23 days ago
Bicycles are stable. In fact you need zero neurons to run a bicycle, all it needs is "power" and a large enough circle to run in.
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malfist 23 days ago
If you can't use a PID for unstable things, why does cruise control exist for motorcycles?
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pinkmuffinere 23 days ago
> No, the bicycle is unstable. PID doesn't work well there.

This is just totally wrong. Stabilizing an unstable system is usually the first goal of controller design. Different systems do require different controllers, but pid is _very often_ perfectly adequate. It’s probably the most used controller structure in general.

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