Dc Motor As Rotary Control Knob
Description
The purpose of this project is to use a DC brushed motor as a bi-directional rotary input device.
The method of operation is that a DC motor generates a voltage proportional to the rate at which it is turned,
and the polarity of the voltage depends on the direction in which it is turned. Using those 2 variables, the motor can be used as a control.
In the following pseudo code, X will contain the value set by the control.
Pseudo code
Loop:
X=X+ADC1
X=X-ADC2
GOTO Loop
Schematic

Components
- M1-Brushed DC motor
- U1-generic op-amp
- U2-generic op-amp
- R1-10k potentiometer
- R2-10k potentiometer
- R3-10k resistor
- R4-10k resistor
- D1-Germanium/Schottky diode
- D2-Germanium/Schottky diode