# Offset Compensation plane

Hi all is worth setting up Offset Compensation in plane i cant fit the pixhawk 2.1 on the Cg it has a large 3 liter fuel tank on the Cg
Its about 340 mm in front CG and and the Gps is 440 mm in front of the Cg
should i setup Offset Compensation on a plane not worry about it?

Hi.
Me, too, I would like to know about Offset Compensation…
In my case, on large VTOL (QuadPlane), CubeBlack is far back from CG (1m+).
All I found on this subject is this:
http://ardupilot.org/copter/docs/common-sensor-offset-compensation.html

It’s always good to add the parameters into your plane such that it can give the EKF the best reading. Ultimately it will figure out what’s going on, but the math is probably a little more accurate if you set the proper offsets.

http://ardupilot.org/plane/docs/common-sensor-offset-compensation.html

not much good my one is less than a meter or does this mean i can put 0.7 of a meter ?

The sensor’s position offsets are specified as 3 values (X, Y and Z) which are distances in meters from the IMU (which can be assumed to be in the middle of the flight controller board) or the vehicle’s center of gravity.

It just depends where you want the calculations to be based on. It can be any datum point that you choose. The CG makes the most sense to me though.

Just to be sure, are these values for below correct?
I have Pixhawk 2,1 Cube & 2x Here GNSS.

Cube X= 0,50m Y=0m Z= -0,05m
GPS1 X= 0,80m Y=0m Z= -0,08m
GPS2 X= 0,73m Y=0m Z= -0,08m

INS_POS1_X,0,5
INS_POS1_Y,0
INS_POS1_Z,-0,05
INS_POS2_X,0,5
INS_POS2_Y,0
INS_POS2_Z,-0,05
INS_POS3_X,0,5
INS_POS3_Y,0
INS_POS3_Z,-0,05
GPS_POS1_X,0,80
GPS_POS1_Y,0
GPS_POS1_Z,-0,08
GPS_POS2_X,0,73
GPS_POS2_Y,0
GPS_POS2_Z,-0,08

Thx