Noise or oscillation?

ArduCopter Copter 4.6
1

Hi!

I have a quadcopter:

  • Battery: 4s2p, total capacity 8000mAh
  • Motors: 2450KV 2306
  • Prop: 5.1x4.5 inch
  • TOW: 2000g ( it is a little bit heavy for this motor/prop combination, but this drone is made for learning how to make a drone, learn to configure before building a properly sized copter for payload)

I have configured harmonic notch filter. Maybe it’s not properly configured?
I was able to perform autotune on pitch and roll.
I was not able to perform autotune on yaw axis because the algorithm was unable to level the drone. The weather was OK, the battery was fresh for yaw autotune, and the autotune was already done on pitch and roll - so I was surprised.

I did a hover test, to have the quad learn the MOT_THST_HOVER.
After checking the log, it seems very noisy. The drone was shaking a little bit on the field. I wouldn’t say it was oscillating, because the movement was pretty random.

  • Is this noise, that needs to be addressed with a filter?
  • Is the tune bad?
  • The compass is too close to the camera lens and the magnetic components inside the lens (focus motor, gears, etc) are influenting compass performance. Can this cause this shaking behaviour? (When I arrived home I fixed this issue by mounting the compass on a bracket to move the sensor further from the camera.)
    This one:
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    image220×220 6.35 KB

Hover test .bin: https://drive.google.com/file/d/1fCSYwV54VYkfH8VeRDy7cy6QSHLtlIFk/view?usp=sharing

I applied some pitch and roll to test the tune: https://drive.google.com/file/d/1rGGXkA_kP6JpfoQfJHDthptjBgJlIJ0P/view?usp=sharing
Noise also can be seen, but the Pitch actual value is following the target.

Can you please take a look at the logs?

Thank you!

2

It’s not to log data for the notch.
Disable Raw IMU and fast harmonic notch in the log bitmask.

The rate PIDs are not typical of a 5" craft, where did you come up with those values?
The vertical acceleration controller gains are misconfigured for the hover throttle this craft has.
Yes, its underpowered/overweight which is a poor decision even for the purpose of this craft.

The tune is poor.

3

I did an autotune without the payload (Olympus camera, about 500g), then added the camera and changed ATC_ACCEL_P/R_MAX values according to TOW change.

Thanks, for pointing out vertical gains misconfiguration! I forgot to change after hover learning. I’ll change PSC_ACCZ_P and PSC_ACCZ_I !

Regarding the underpowered copter: For this payload, this purpose a proper copter is an X8 copter with 8-10inch props, 6s battery. But I haven’t had the experience to make a big craft for the first time. It’s more expensive to crash, more complex for the first time, it would be “too big bite” to swallow for first time. Now I have some experience in biulding. Now I have to gain experience in configuring, flying :slight_smile:

4

All these configuration errors are avoidable by using the ArduPilot methodic configurator software.

For bigger copters it is irresponsible not to use it.

1 Like
5

@amilcarlucas for “bigger copter” you mean 10inch and above range, right?