Converting speed to voltage, which is better?

Question

Do it yourself

I ask the advice of theorists) There is a certain wheel, say a bicycle wheel, which rotates at a not very high speed (let's say ten revolutions per minute). It is necessary to somehow fix how many revolutions it has made and, depending on this, output voltage to the output, if it spins quickly, say 5 volts, it doesn’t spin 0. I don’t want to use any duin for this (although it can), I would like to get by with an analog circuit number. Are there any options or is it better not to be smart and use a microcontroller?

Answer 1

Magnets for rim/spokes and spool for fork. Next is a diode bridge and a smoothing capacitor.

Answer 2

It looks like you need a regular transistor switch. To the base - the current from the generator on the wheel through the tuning resistor. On the collector / emitter - your 5 volts. With a resistor, we select the value of the opening of the transistor that you need.

Answer 3

There are many options, but the fact that the wheel is bicycle spoils everything.
we exclude the optical sensor and the ultrasonic sensor - dirt.
there remains contact and magnetic
magnetic - we fix the magnet to a convenient point, and using integration on the resistor and capacitor we get the voltage, you can flavor it with an amplifier on the opamp before integration and after, by adjusting the gain you can achieve the desired range. well, or take a fool and count the impulses.
contact - for example, a microswitch from a mouse, we hook a lever to it so that the needle, when passing, has the same integration and or foolishness and count the impulses.
Or you can make a knight's move and take a generator for a bicycle, it will immediately give out voltage depending on the speed.