Strange result of add actor rotation

I print actor’s rotation before and after add actor local rotation and the delta rotation I added.
I got a wrong number on pitch. I added 0 on pitch. But it always change a little bit on pitch. How to fix it?

P=0.000000 Y=-179.908783 R=0.002523  before AddActorLocalRotation
P=0.000000 Y=0.190325 R=0.007987     delta rotation
P=-0.000007 Y=-179.718460 R=0.010510 after AddActorLocalRotation
Hello                                end of a tick
P=-0.000007 Y=-179.718460 R=0.010510
P=0.000000 Y=0.250564 R=0.013617
P=-0.000055 Y=-179.467896 R=0.024128
P=-0.000055 Y=-179.467896 R=0.024128
P=0.000000 Y=0.332203 R=0.022264
P=-0.000198 Y=-179.135696 R=0.046391

Try removing the connection from pitch in make rotator and see if you still get those results. If you don’t, it’s either pitch speed or whatever pitch speed multiplies with.

pitch is always 0. I have printed the delta rotation in middle of the rotation before and after add rotation.
P=0.000000 Y=-179.908783 R=0.002523 the rotation before add actor local location
P=0.000000 Y=0.190325 R=0.007987 the delta rotation
P=-0.000007 Y=-179.718460 R=0.010510 the rotation after add actor local location
you can see there is a strange result on pitch.

Well if you are not willing to try and see if it stays 0 after removing connections to the pitch, then I can’t help you.

OK! I tried! And the result is the same! pitch always have a strange change.

P=0.000000 Y=-179.892685 R=0.003218
P=0.000000 Y=0.183181 R=0.007806
P=-0.000014 Y=-179.709503 R=0.011024
P=-0.000014 Y=-179.709503 R=0.011024
P=0.000000 Y=0.277078 R=0.015550
P=-0.000068 Y=-179.432419 R=0.026574
P=-0.000068 Y=-179.432419 R=0.026574
P=0.000000 Y=0.377286 R=0.026439
P=-0.000232 Y=-179.055130 R=0.053012

And what? you got any idea now?

I think this might actually be a bug - if nothing is connected into Pitch, then the value shouldn’t change. The values you have posted also seem to be big to be inaccuracies for 32-bit float. I would change the section for this to the Bug Reports section.