Sensorless position control issues

[zpc128]

Hello everyone, I learned a lot from seeing these technical discussions.
I want to realize sensorless position control of brushless motors: for example, when the motor stops, manually rotate the motor shaft several times, can the angle and direction of the motor shaft change be detected by HFI45 or other methods, and then the motor can be pulled back to its original position by control when needed?

 

[scianiac]

HFI has no absolute reference so unless the motor is still powered with HFI running the whole time no, what you are looking for is an absolute encoder like an AS5047P that will be able to return the motor to a set position regardless. Various other encoders are supposed by VESC but that is the one of the most common. The only annoying part I've run into with encoders so far is some hardware has hall filters that have to be disabled.