"Does your code fuse the GPS heading data into the calculations?"

"I have only used barometric sensors in weather station applications so really don't know.  It depends on whether the pressure is actually fused to the other data by the software.  
What I was trying to do is to enhance the heading precision and…"

"Mario,

I've put my project on hold due to other priorities but the last I worked on it was with a MPU-9150 board and code supplied by Pansenti. This worked very well in my quick tests.
Pansenti has taken down all of their stuff (not sure why) but I…"

"I see it stabilize but it starts drifting again as soon as it is moved to a new orientation. Still very good performance and your support to ArduIMU is much appreciated! Thanks My application requires good yaw (heading) performance so I would like…"

"Thanks!! That was it. I had wondered about this as a problem but didn't know where in the code to fix it. I made the change to FreeIMU.cpp in getQ() by adding the second #elif i.e.:

#if IS_9DOM()
#if HAS_AXIS_ALIGNED()
AHRSupdate(val[3] * M_PI/180,…"

"There is a new release of FreeIMU with the updated calibration routines at:
http://bazaar.launchpad.net/~fabio-varesano/freeimu/trunk/revision/18
Also attached is a calibration.h file with how perfect sensors on the ArduIMU running FreeIMU should…"

"After the huge response I got from this post <g>, I did the port myself.  This is for ArduIMU V3 and entailed creating an MPU-6000 (SPI) library, verifying the FreeIMU library for the HMC58X3 worked on the ArduIMU hardware, and updating FreeIMU.cpp…"