ArduCopter 3.6.10 altitude drop while flying with rtk

Huibean · October 16, 2019, 3:44pm

Flying with rtk, just altitude keep drop and climb, seems like the EKF just not refresh the altitude
log file https://drive.google.com/open?id=1FjwJXhfhjVjigDzlxsT5ounfbyyNrTYv

Huibean · October 21, 2019, 2:18pm

For serious situation the altitude Estimate totally stop working making the drone can not land in ALT Hold ,Loiter ,RTL Mode

Huibean · October 21, 2019, 3:42pm

just found this useful video

Huibean · October 21, 2019, 5:07pm

@tridge @priseborough @rmackay9 , do you have any idea on this?

Huibean · October 22, 2019, 3:10am

just check all the values in dataflash log, only the NKF5.ePos seems to related with EKF altitude none updated

Huibean · October 22, 2019, 9:26am

github.com

ArduPilot/ardupilot/blob/7b0da8970839f5dfc3bc2b96d5391f1d5e15b6be/libraries/AP_NavEKF2/AP_NavEKF2_Outputs.cpp#L283


            posNE.x = 0.0f;
            posNE.y = 0.0f;
            return false;
        }
    }
    return false;
}


// Write the last calculated D position of the body frame origin relative to the EKF origin (m).
// Return true if the estimate is valid
bool NavEKF2_core::getPosD(float &posD) const
{
    // The EKF always has a height estimate regardless of mode of operation
    // Correct for the IMU offset in body frame (EKF calculations are at the IMU)
    // Also correct for changes to the origin height
    if ((frontend->_originHgtMode & (1<<2)) == 0) {
        // Any sensor height drift corrections relative to the WGS-84 reference are applied to the origin.
        posD = outputDataNew.position.z + posOffsetNED.z;
    } else {
        // The origin height is static and corrections are applied to the local vertical position
        // so that height returned by getLLH() = height returned by getOriginLLH - posD

Trying to find out whether the EKF use the gps data or not, is this condition can be replay with dataflash log?