Leveling: Feet vs. Motors bubble discrepancy.

Joined
Jul 26, 2016
Messages
1,539
Reaction score
479
Was doing an IMU and checked the level on the table the P4 was sitting on. Looked good there.

However, I also put the level on top of the motor shafts (No props installed) and the level was showing a fore/aft tilt of 1/4 bubble. Side to side was good.

So which do you level for? The feet or the motors? Some say motors, but others say the feet. I don't know if DJI has a preference for how the IMU is placed with regards to the two.
 
Joined
Mar 31, 2015
Messages
659
Reaction score
194
Age
43
Location
Albuquerque,NM
Was doing an IMU and checked the level on the table the P4 was sitting on. Looked good there.

However, I also put the level on top of the motor shafts (No props installed) and the level was showing a fore/aft tilt of 1/4 bubble. Side to side was good.

So which do you level for? The feet or the motors? Some say motors, but others say the feet. I don't know if DJI has a preference for how the IMU is placed with regards to the two.
on P4, if you level the legs shouldn't the motors also be good? back in the day i used to put a piece of glass atop the motors then double check the level because of the foamy piece on the landing gears. is your level showing the motor tilt?
 
Joined
Sep 2, 2016
Messages
38
Reaction score
18
Age
39
Is it possible that it is due to the motors being slightly tilted to reduce the effects of vortex ring state (VRS)?
 
Joined
Jul 26, 2016
Messages
1,539
Reaction score
479
on P4, if you level the legs shouldn't the motors also be good? back in the day i used to put a piece of glass atop the motors then double check the level because of the foamy piece on the landing gears. is your level showing the motor tilt?
There is a difference between the feet and motors on mine, about 1/4 bubble's worth. I doubt if it is from the rubber feet to make that much difference.

Prior, I had a bad level that didn't match against a longer carpenter's (5 foot) level. It showed I needed to raise the nose a 1/4 bubble worth back then which seemed to help my negative landing altitude number (-50 feet landing vs. 0 foot take-off.). Afterwards with the new longer level, the landing altitude numbers are much better, although maybe -6 to -10 feet now.

Now I show the nose still would need to go up about another 1/4 bubble measuring with the level on the motor shafts alone. If this is true, then the nose was off 1/2 bubble from doing it with the feet as well *** the bad level prior that is now garbage. Seems a half bubble is a lot, but don't know.

The side-to-side is the same front and back on both motors and the feet, just the fore/aft is different.
 

New Threads

Forum statistics

Threads
136,140
Messages
1,408,055
Members
99,057
Latest member
Gennady