Poshold did not work with 3.5.1

Using Pixracer with 3.5.1 and a 250 quad copter

Took off in stabilize mode and then switch to Position Hold mode. Copter drifted in the wind in one direction.
Reposition the copter and it continued in that same direction as if in Altitude Hold.

Logs show no errors or indication of failure.


Also the log file date/time did not get set or changed.


I made several flights yesterday with my Pixracer 210 with 3.5Rc1 and everything performed great in all modes. I did have some connection problems with the ESP8266 WiFi radio while trying to calibrate the compass that didn’t seem to be an problem in current stable version.

Not trying EKF3 I see in your parameters? Seems to be solid.

@iseries (Mike)
I’m on the road so it’s slightly difficult for me to analyse log files at the moment but it’s likely one of two problems:

  • the vehicle didn’t change to PosHold because the EKF’s position estimate wasn’t good (i.e no GPS lock). The green light while in stabilize mode is slightly deceptive. It means the vehicle has GPS lock but the EKF may still not have a good position estimate. This is unchanged from AC3.4 but we may change it in a later release candidate.
  • the transmitter trims were off slightly so PosHold thought you wanted to move the vehicle. This can be fixed by re-doing the RC calibration or fix the trims on the transmitter.

I tested PosHold yesterday in master. That’s slightly different from AC3.5-rc1 but still, I’m pretty confident PosHold should work.

Thanks for the testing and feedback.

Found it. The trim was clicked on to the left. Couldn’t see it in the graph or looking at the radio. It kind of showed it was in the center but it didn’t look like the other trims so I clicked it once and it beep to tell me it was centered and now looks like the others. The plot on the graph was hard to see but was 11 units lower than it should be.

When I calibrated the radio I made sure all values were as close as possible to 1500 so I would know. Should have checked that second. Now I know how to create a slow movement in one direction that is controlled. Could maybe use it for a panorama.

Looks like you had a good trip to Australia.



Ah, great that it’s sorted.
Yes, the trip was great, thanks!