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Electromagnetic levitation
I posted the old version of the schematic. The source code simply read the value of the hall sensor and with PID, or only proportional way calculate the value for the PWM output to the transistor.
Now I am working on other idea of using two hall sensor one on the bottom of the coil and one on the top. The extra one on the top will show the error which coil add to the sensor on the bottom which in fact must measure ONLY the magnetic field of the levitating magnet.
Regards
Martin Nikiforov