After repairs I now have a simpler plane. I disabled the GPS partway through this longish mission on a day with absolutely no wind (Oh - and a working AirSpeed sensor!) and got this.
I think it looks pretty good (as far as dead reckoning goes) - or maybe I’m missing something?
@timtuxworth that worked, but wasn’t quite a correct test. You should have made RC7 go above 1800 to disable GPS. The switching to a non-GPS EKF source isn’t quite the same thing as disabling GPS.
The results were good though:
about 125m error in 5 minutes, which is 25 meters/minute.
The result was the same for both of your IMUs:
this is definately better than average for this type of dead-reckoning test!
Thanks Tridge. BTW - the Zealot H743 has 3 IMUs.
I’ll try to test again with low wind and (and flipping the GPS switch all the way high). Weather dependent - but it will happen.
Great weather today. 0 m/s windspeed (measured at the ground)
I got 3 flights, switched off GPS on each and switched to second EKF configuration to avoid fallback to DCM. I let the plane fly as long as I felt safe on no GPS. I think there might have been a breeze up higher as there was some drift especially on the second flight. This was running on 4.4.0 beta 4.
I’m kind of disappointed, is this the best we can expect? Should I be doing something different?
Another flight at a different location. 0m/s windspeed where I was standing. Same plane, same FC. After about 3 minutes it was off by about 150m so I pulled the trigger and re-enabled the GPS. Looking forward to some more ideas @tridge …
I would try doing few circles before disabling GPS.
Other than that optical flow with appropriate rangefinder could help further constraining drift even when the wind is changing.
Could you tell me how to multiply arsp.airspeed with ctun.e2t, I could not do it with mission planner, thanks
Tridge and I have been using mavexplorer.py. You might also be able to do it in plot.ardupilot.org
thanks, I did it use this link