Dear all,
After lots of reading I think I’am losing my mind. I have a APM 2.5 with a 3DR uBlox GPS with Compass Kit.
Now I’ve decided that my AHRS_Orientation needs to be adjusted to;
Roll = 90 Because it’s on it’s right side facing forward.
Yaw = 180 Because the direction arrow is backwards
It seems like this is just not available in the APM planner parameters,
Is there a different way? No I cannot just change the Ardupilot on its otherside
Thank you!
dear peter , are you not confusing roll and yaw? because if you say “90 Because it’s on it’s right side facing forward” i think it’s a yaw.
If you are sure that you need Yaw=180 and Roll=90, then yes, that option doesn’t seem available.
However, option 32 Roll270Pitch180 is equivalent to the rotation you need.
Still, I think it is problematic that the list of available AHRS_Orientation options which are available do no follow the aerospace Euler angles convention:
-180<yaw<=180
-90<pitch<=90
-90<roll<=90
I’ll probably raise an issue about it.
Dear Samys13,
Edit:::::::::
I think I am confused… seeying the issue description Georacer wrote down…
Thank you for your comment, I don’t see how I could confuse the 90" roll with Yaw;
When I have a plane in forward direction, I would use my ailerons, which means the plane rolls to the right, therefore - The flightcontroller(FC) is on it’s right side, where the top of the FC is facing towards the right when banked 90".
The YAW problem/requirement comes in that the FC will be mounted on it side in a Bixler 3 where the USB port should be on the top side (thats why the Roll is needed). The FC will be mounted on the right side of the bixler and therefor I need a Yaw 180. (sorry this is very confusing to do without images). (Not at home at the moment).
Still, if you think Im confused you’re more than welcome to help 
Dear Georacer,
Thank you, I will try the option 32, Roll270, Pitch 180, I cannot really wrap my mind around it, but it will probably be same result but over a different axes…
If I use option 32, and look in Mission Planner and I see my Rolls, pitches en compas direction the correct way, that means it is working right?
Do I need to do something with my external compass values? It’s going to be mounted in a normal way.
I think you don’t need to do anything with the external compass, if it’s mounted upright and facing forward.
http://diydrones.com/m/discussion?id=705844%3ATopic%3A1322806
Found a different user with the exact question. I cannot really use the other side if the fuselage.