
Magnetocapacitance - peter_d_sherman
https://en.wikipedia.org/wiki/Magnetocapacitance
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yummypaint
This sounds vaguely similar to how electret microphones work, where the sound
waves compress a dielectric and change the capacitance. If you apply a bias
beforehand to put some amount of charge q across the capacitor, q=cv so the
voltage v measured accross it changes inversely with capacitance. This is
probably best for capturing dynamics.

An alternative method is to make the device part of an oscillator where its
capacitance modulates the frequency. This would be better for precision
measurements on a slower timescale. I wonder how the repeatability would
compare with a hall probe.

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anfractuosity
Interesting not heard of that before.

There's also -
[https://en.wikipedia.org/wiki/Magnetoresistance](https://en.wikipedia.org/wiki/Magnetoresistance)
along with the hall-effect, which are used for sensing magnetic fields.

This is quite a nice video of someone making a DIY hall effect sensor -
[https://www.youtube.com/watch?v=T1eLp4xfrRo](https://www.youtube.com/watch?v=T1eLp4xfrRo)

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thesuperbigfrog
How it is being used in industrial products:
[https://youtu.be/aW2LvQUcwqc](https://youtu.be/aW2LvQUcwqc)

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Jupe
Thanks for sharing - clear as mud now! ;)

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myself248
Not tagged as a stub, but it sure could use some love. I wonder whether it's
enough of an effect to be useful. Hall-effect sensors are all over in certain
types of motors and encoders; might there be cases where they're not suitable
and a magnetocapacitive effect would be applicable?

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MichaelZuo
This is related to the idea of the memristor
[https://en.wikipedia.org/wiki/Memristor](https://en.wikipedia.org/wiki/Memristor)

