I asked this question 13 days ago electronics.stackexchange. DC motor has to stop always same spot. If we take the area where the motor starts to rotate as 0, the motor should always stop at 0 degrees, not 3 or 5 (until 1, 2 is okay I guess.)
They suggest me to use hall effect sensor. I run into this question in this link stackoverflow . OP says it is not working.
OP says: What I managed to do at this moment, is calibrate ESC through Arduino and also to brake immediately when the magnet reached the sensor after I kill the throttle. However, I cannot get the magnet to stop directly below the hall sensor.
I don't have any DC motor yet so I can't try but I will try it soon. What I want to ask is;
In second link, OP couldn't manage to get this work with hall effect and magnet. IS there another way ?
if I use switch for drive DC motor, I can instantly brake motor with connecting the positive and negative terminals of the motor. If I get feedback from hall sensor, maybe I can stop it with hard brake. So is it good idea to use relay for stopping dc motor when I get feedback from hall effect sensor ?
Here is a schematic: