How to make loiter more accurate with RTK

Hi

In order to avoid GPS drift, I change GNSS to rtk, it can provide position correctly in ±1cm.

although the ardupilot can receiver accurate position information,

drone still have flight drift in loiter mode ,the range around 45 cm.

【Video here!!!】

as i know, there are some weighting(IMU/GPS) parameters can be adjust if ekf is used,

related item such as:

EKF_POS_DELAY

EKF_POSNE_NOISE

EKF_POS_GATE

EKF_RNG_GATE (maybe?)

EKF_VEL_GATE

EKF_VEL_DELAY

more…

Does someone have experience tuning these,

any idea or advice please discus with me, thanks

of course, i’m going to have more experiments to figure out these ekf parameters.

At present the Ardupilot internal representation of GPS values is only to 7 decimal places and cannot give more than +/- 1.5cm accuracy, no matter what system you are using.

We are setting up a much higher accuracy RTK system (+/-6mm) but as the RTK corrections have to go through Ardupilot, which fortunately does not modify the accuracy, so as long as GNSS can do the logging you will get better accuracy. If you are relying on the Ardupilot logs the you are stuck with 1e7 or +/-1.5cm.

Sky54545,

Randy MacKay or Leonard Hall may be able to answer your question.

Dave