Trouble adjusting yaw PID values

[Tommie]

Hello,

I finished building my quadcopter (44cm axis to axis), however I am having trouble adjusting the PID values for the yaw axis:

With the default values (P: 8.5, I: 0, D: 0) the copter tends to drift clockwise (gyro measurement ~2-3); I can keep it steady using the yaw stick, but its kind of annoying.
Increasing P showed no improvement, while increasing I did; after a while however, the copter starts to rotate clockwise and even speeds up (gyro shows values of up to 12).

Any ideas how to improve stability?

[fr3d]

trim a bit your yaw rather than playing with yaw PiDs

[Tommie]

That sounds more like masking the symptom than fixing the problem.
According to the GUI, my yaw axis is dead center, but the copter keeps on rotating to the right.

I also noticed that the problem gets worse when ascending; I'm not sure how to fix this.

When holding the copter in my hand and turning it, it seems to be working harder against counterclockwise turns much than the other way; what could be the reason for this?

[PatrikE]

Your motors is probobly tilted slightly to right.
It gives the effects you describe.

Try to get them all paralell.
Or slightly rotated to left.

[Tommie]

I checked all motors, but everything looks fine to me - I also tried turing them 180° to see whether anything changes, but nothing happened.
I am using these motors: http://www.hobbyking.com/hobbyking/stor ... ouse_.html
They are bolted to two aluminum beams, being helt together tightly by two discs of plywood. So you see, there is not much room for misalignment

[kos]

I checked all motors, but everything looks fine to me

are motor 10 and 11 counter clock wise rotating ?

[Tommie]

Yes, they are.

[PatrikE]

Calibrated the esc's Max and min endpoints.?

[Tommie]

Yes, I did it several times now; however, I am still experiencing the drift around the yaw axis.

[Olaf.J]

Yes, I did it several times now; however, I am still experiencing the drift around the yaw axis.

Hi, had you any success with your problem? I have the same issue. And if I try to eliminate the yaw drift by trimming the the copter, the drift reappears to one side, if I increase or decrease throttle...

[Olaf.J]

Yes, I did it several times now; however, I am still experiencing the drift around the yaw axis.

Hi, I had the same problem with yaw. When I checked the motor-temperatur, the counterclockwise-rotating motors were very hot, the other both not.
I solved it the following way:

I set all the PID-values for yaw to 0 and trimmed the yaw at the transmitter so that I had a value of 1500 at the receiver. Then I tried to hoover - the copter rotated counterclockwise when not using the yaw-stick. So I knew, that there was something not o.k. with the hardware. Then I trimmed the hardware by putting a washer under one screw fixing the motor, wo the motor was tilt a little bit to reduce the rotation. That worked very fine - I only needed one washer at one motor and the yaw rotation was almost completely eliminated. Then I activated PID-settings and then it worked fine - and the motors all have similar temperature now