Good day everybody,
We experienced a crash recently on a copter using ArduCopter 3.5.4 on a Pixhawk. We had a GPS glitch (which last for about 14 seconds) while flying in stabilize. Then, a couple of seconds after the primary EKF switched multiple times (see Figure 1).
This caused major oscillations on the copter and we finally crashed. We found that there’s a significant delta between the estimated attitude of both EKFs. So, switching from one to the other causes significant discontinuities in the actual attitude estimation. Figure 2 shows the estimated pitch for both EKFs and we clearly see that there’s a drift between them. Indeed, looking at our previous dataflash logs, we observed that most of the time.
In the short term, we just disable the second EKF. However, we still want to investigate
The log file is available here:
- Why does a GPS glitch causes the primary EKF to change?
- What can cause so much difference in the estimated attitude of both EKF?
Your help is very appreciated.