I have a pixhawk board on an aeroquad cyclone frame.Using zeal tape for vibration and mu metal under pixhawk. I am using a taranis and x8r receiver.Also using 3s 5300 mah lipo.I take off in loiter mode and flys great in hover. After landing about 3minutes I downloaded data flash logs which are attached.everything looks fine except (MAG Z field Is high). Otherwise flys very good. Can someone please look at dataflash log and give some advise to reduce Z MAG field?
have you tried without the mu metal? I believe it is slightly magnetic itself. Are you using an external compass? with separation mu metal should be unnecessary.
I have not tried removing Mu metal.i will try tonight. I’m not understanding how mu metal would contribute to increased magnetic interference. I am using 3dr robotics external compass/mag. Still getting high Z readings.
If it is magnetic the compass will see it if close/large enough
Yes mu metal is used in magnetic shielding, but can affect the compass too. The way I understand it it acts like a conduit routing magnetic flux through it, it seems possible to me that mu metal could be used to aim magnetic interference where it isn’t wanted. Not saying that is happening in your case, I think its just the slight magnetism of the mu metal possibly affecting things.
Are you using any steel or even stainless steel to mount the compass? that’s another possibility.
with an external compass on a mast mu metal should not be needed. If you still have issues it may be loops in the wiring, keep power leads together and preferably twisted to avoid magnet loops. Its better to prevent the magnetic fields in the first place than to try and shield them.
let us know how you get on with out the mu metal
actually, are you sure z is high? yours is similar to mine looking at my logs, I am in the UK, at about 50 degrees north.
Auto Analysis says -
Test: Compass = FAIL - Large compass off params (X:-110.00, Y:-42.00, Z:-160.00) Large compass offset in MAG data: Z: -160.00
Large change in mag_field (35.06%) Max mag field length (560.60) > recommended (550.00)
values of -150 - 150 are whats recommended so yeah Z is a little too high for optimum.
Compass should be mounted away from any and all metal objects as they will interfere with the compass, I’m guessing you have something metal below the compass/gps module.
Mag field length at 560.60 should also come down a bit then, mines at 530 and flies just fine.
ah yes, i was looking at MagZ, not OffsZ, My OffsZ is much lower.