The encoder offset calibration is not well understood. Who can explain it?

1

The encoder offset calibration is not well understood. Who can explain it?

2

Hi

It senses the difference between the fases of the motor and the encoder channels.

Cheers

3

Hello
thank you very much for your answer.
Can the offset calibration be calibrated only once?

4

Hi

I think so, why?

Cheers

5

Hi
Because I want to save the calibration data after power off, it seems that the motor does not work properly when power is turned on again.

6

Hi

Why do you want to save it?

Cheers

7

Did you get a chance to read through this documentation?

8

Oskar, I have some questions on offset calibration as well and seems like an appropriate topic to ask.

  1. how close can you get to motor zero phase by just energizing a single phase for start_lock_duration?
  2. does scanning forward and backward have self-aligning effect?
9

The start_lock_duration is just a way to get the rotor roughly into place to get ready to do the scan. The actual correlation between phases and encoder response is only evaluated during the forward and reverse scan.
Going in both directions should hopefully cancel out some friction drag, if it’s the same in both directions.

10

Thank you for your answer. I was curious because it seemed count on forward steps and backward steps were always little different (like 4~5 with 4096 cpr) and final value is between the two.

11

Thank you very much, the problem has been solved.

12

hi
Thank you very much, I mainly want to save the parameters after one calibration, and you can enter the closed-loop control in one step after restarting.

13

can somebody elaborate a bit on this topic? specifically related to variables in the encoder and motor config, and what they mean. Say offset, calib_scan_distance, etc