RPM Notch Filter not working correctly with CANBUS ESCs

[danielm1199 (Daniel)]

Hi everyone,

I’m using CANBUS ESCs, and I’ve verified that RPM telemetry is working correctly. I’m getting valid and stable RPM readings from all motors.

I’ve configured the RPM Notch Filter settings as expected, but I’m running into an issue:
Instead of seeing four separate RPM notches, I only see a single line, the notch line itself looks straight, as if the filter isn’t actually receiving or reacting to RPM data at all.

Are there any special settings or limitations when using CANBUS ESCs with the RPM notch filter?

Is there something different that needs to be configured compared to traditional PWM ESCs?

If anyone has experience with RPM notch filtering using CAN ESCs, I’d really appreciate any insight.

Thanks in advance!

[amilcarlucas]

To get multiple notch filters you need to update to ArduCopter 4.6.3 and:

1. enable “multisource” bit in INS_HNTCH_OPTS
2. INS_HNTCH_ENABLE = 1
3. INS_HNTCH_MODE = ESC telemetry
4. INS_HNTCH_REF = 1
5. INS_HNTCH_FM_RAT = 0.7
6. INS_HNTCH_BW = INS_HNTCH_FREQ / 4

[danielm1199 (Daniel)]

Hi!

Thank you for your reply.

Please see the attached bin log.
I still can’t get it to work for some reason. I’m getting correct RPM data in the log, but in the filter review tool, I see the following: (the notch lines itself looks straight)

Also, please see the notch filter parameters I’ve configured:

[amilcarlucas]

Set the INS_HNTCH_REF to 1

0 is wrong and causes the effect that you are seeing.

And set
INS_HNTCH_ATT = 10
INS_HNTCH_FM_RAT = 0.7

[danielm1199 (Daniel)]

It worked, thank you!!