Way to read data transfer at each individual UART port?

There’s no downside to having that boot delay. It’s meant to allow CAN devices to boot up before the flight controller, but I’ve also found it helps with sparks and bad voltages while connecting the battery. Obviously it doesnt remove those bad voltages, but at least the board will wait a bit and voltages might be stable.

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@xfacta
Not sure if I’m doing the right thing by reviving this thread or if I should make a new thread for this, let me know if you think I should start a new thread.

I’m trying to get a proper tune on my newer quad (same hardware as the hex mentioned in this thread but an all up weight of 1.1kg). I’ve achieved a decent stable hover. I would like to move on to auto-tune and am setting up a thrust based notch filter based on the documentation here. I’m starting to work with the settings you suggested:

INS_HNTCH_ENABLE,1   <- set this the refresh to see the rest
INS_HNTCH_MODE,1
INS_HNTCH_REF,0.12
INS_HNTCH_FREQ,90
INS_HNTCH_BW,40
INS_HNTCH_FM_RAT,0.7
INS_LOG_BAT_MASK,1
INS_LOG_BAT_OPT,4

To identify the primary notch frequency for INS_HNTCH_FREQ using the mission planner FFT utility I did a flight test without any filtering enabled, flying in stabilize and alt hold mode for a couple of minutes and then switching to loiter for the rest of the flight (log attached). The FFT results look very “dirty” and I cannot make out any clear frequency peaks:

Despite the fact that the dynamic harmonic notch filtering documentation page talks a bit about larger vehicles having “dirty” FFT profiles, I’m a bit unsure if I’m doing something incorrectly. I’m looking for any advice on how to set up notch filters with such “dirty” FFT profiles.

Log

BR,
Arth

You’ll need these settings:

Part of the problem, stability issues, is the motors are hitting minimums, so you’ll need to add some payload or fit smaller props.

Ah thanks, I did not realize that a linear ordinate would make it easier to recognize the peaks. I used the notch you suggested and did a test flight, it looks like the notch filter works quite well with those settings.

Log for reference.

Part of the problem, stability issues, is the motors are hitting minimums, so you’ll need to add some payload or fit smaller props.

Alright, I’m going to double my battery capacity and that should add about ~600g of weight.

Couple more questions:

  • Do I need to tweak any settings for the low pass filters?
  • Is there a way to limit the total current drawn from the battery? I would like to limit the current to 30A, MOT_BAT_CURR_MAX drops the throttle to “as low as 60%” but for my vehicle most of the time it is already below 60% while the current increases above 30A. Especially during RTL, for the rest of the flight I can keep the current low by executing maneuvers that are not aggressive but during RTL, I have very little control and the current spikes quite a bit.
  • I have a vehicle that can safely fly all flight modes and is pretty stable. Do you think I can safely move on to auto-tuning now?

BR,
Arth