I am using arducopter 4.1.0-dev master version on 2 different boards, one is Omnibusf4SD running omnibusf4pro firmware, second is Pixhawk 2.4.8 running pixhawk1 firmware. I have setup these 2 boards on separate quadcopter frames. Both using Here+ RTK GPS. For both quadcopters, i am taking RTK GPS as primary EKF3 ALT source by setting EK3_ALT_SOURCE to 2. Also, I have kept EK3_ALT_M_NSE to default i.e. 2 for both quadcopters.
Now when using the same Here+ RTK GPS on these 2 quads one by one, there is difference in the performance of maintaining the altitude during flight while moving at a constant height(desired altitude) in guided mode.
On Pixhawk 2.4.8, GPS.Alt log of RTK GPS have altitude drift of around or within 0.5 meter, POS.Alt log of EKF3 have altitude drift of around or within 0.2-0.3 meter. On Omnibusf4SD, GPS.Alt log of RTK GPS have altitude drift of around 2 meters, POS.Alt log of EKF3 have altitude drift of around 1-1.5 meters.
Everything seems more consistent on pixhawk in every flight, but on omnibus, flights are not consistent in terms of maintaining the right altitude, from the logs on omnibus i have seen a few times even when drone is on the ground still GPS.Alt and POS.Alt vary from about 6-10 meters but satellites count and GPS.status not changing during that time. What possibly causing these differences between performance of same RTK GPS on different boards ?
I also feel that RTK GPS and baro both are not very reliable in terms of consistency in maintaining the right altitude during multiple flights. Cause i can analyse from the logs that only if baro and GPS raw altitudes able to keep themselves within 1 meter altitude drift, only then EKF able to play its part in maintaining the right altitude during multiple flights and that’s what i am looking for.
Below i am attaching 2 logs and build pictures of both quadcopters:
- pixhawk logs and build
pixhawk log1
pixhawk log2
- omnibus logs and build
omnibus log1
omnibus log2
