Periodic position estimation error

Hi.

I use PX4 v1.4.2. And GPS receiver uses Piksi(Swift Navigation).
I am challenging to incorporate Piksi’s driver perfectly.
Currently, it seems that the flight controller is able to recognize the position information, but it gets out of fix periodically, causing a big error.
I think that such values are not shown in raw GPS data, so is there any need for setting?
Or simply, is my program wrong?

I’ve had similar issues, solved it by increasing the parameters EKF2_*_GATE. Some documentation can be found here https://dev.px4.io/en/tutorials/tuning_the_ecl_ekf.html. However this doesn’t fix the GPS losing RTK.

Thank you Bart.

As you say, by adjusting the parameters of the Kalman filter, I was able to reduce errors.
I do not understand fundamentally, so I will study more.

It is sort of a statistical check to verify if the measurements are good. If the measurements are not good, they get rejected. However if the parameters/thresholds are too low, it also rejects many good measurements.

I see!
Thank you Bart.
Your advice was very helpful.