Servers by jDrones

MP shows non-zero wind speed, logs (NKF2) show zero wind speed


(Alexander Marinšek) #1

Firs of all, I’m new to the community, so shout out to all of the amazing developers, who design and maintain Ardupilot.

Recently I started flying a multirotor with Ardupilot (Pixhawk 1) and I wish to do some post-flight analysis. I set up a simple mission, went out to fly and while in flight using mission planner I could see all of the desired data in real-time, including estimated wind speed and direction. Afterwards I downloaded the logs, from which I managed to get most of the flight data, without wind (and air) speed data.
I tried visualizing the data using MAVExplorer (Ubuntu machine), but the logs NKF2.VWN NKF2.VWE NKF7.VWN NKF7.VWE are all zero. I should point out, that I was flying without an airspeed sensor and with normal GPS (not RTK), but still managed to see estimate wind speed and direction values in MP.

Before flying I set all of the parameters as proposed in the Ardupilot documentation and rebooted the Pixhawk:

  • EKF_ENABLE = 0 (turns off the legacy EKF)
  • EK2_ENABLE = 1 (turns on EKF2)
  • EK2_IMU_MASK = 3 (Instructs EKF2 to run two instances, one for IMU1 (MPU6000) and one for IMU2 (LDG20H + LSM303D)
  • AHRS_EKF_TYPE = 2 (tells the flight control system to use EKF2
  • LOG_BITMASK = 131071 (logs 50Hz data from startup)

I also tried setting the log_bitmask to 45054 (NearlyAll), but the result was the same.

How come I can see the wind speed and direction during flight in MP, but the logs show wind speed zero and how can I obtain a log file including wind data?

There were other members posting similar questions some time ago, but I couldn’t find a proper answer:
How to enable wind speed logging?
Zero EKF wind speeds in copter?
Airspeed reporting in MAVLINK
Where can I find the airspeed value in the log?

Cheers,
Alex