You can use Hall effect sensors to sense chainwheel teeth. Two sensors and you can get quadrature and direction. I've done that on a mobile robot. With analog-output Hall effect sensors and some processing, you can get sub-degree precision, although 0.05 degree is asking a lot.
We're trying to measure aerodynamic drag, thing is there are huge vertical forces (weight of rider pressing down on pedal) and relatively small horizontal forces (due to drag). So if we don't know the angle accurately, we can't separate out the components - make sense?
You can use Hall effect sensors to sense chainwheel teeth. Two sensors and you can get quadrature and direction. I've done that on a mobile robot. With analog-output Hall effect sensors and some processing, you can get sub-degree precision, although 0.05 degree is asking a lot.
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