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  3. Mainline PX4 or voxl-px4 bug causing inconsistent Vz and z estimates by EKF2?

Mainline PX4 or voxl-px4 bug causing inconsistent Vz and z estimates by EKF2?

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  • Cliff WongC Cliff Wong

    Hey there, if you are flying solely with VIO (no GPS), suggest loading our indoor estimator params to add to the current setup on PX4. Outdoor vio+gps is here. These set the vio sensitivity that is in line with the suggestions mention on your PX4 forum's thread. Also we're assuming that extrinsics.conf values have not changed and are same as the factory settings.

    Secondly, if you run voxl-inspect-pose vvhub_body_wrt_local on voxl2 it will apply the extrinsics and output pose that should be inline w/PX4's local position. If those values are correct, then we're looking at a PX4 tuning/config issue (we can still help).

    One thing that looks weird on your PX4 flight log is Roll and Yaw rates are not keeping up w/respective setpoints (noisy). [Hence, thirdly, suggest an] IMU calibration on the PX4 side.

    Lastly in /etc/modalai/voxl-vision-hub.conf there's a parameter called en_reset_vio_if_initialized_inverted. It is set to true as it's to account if vio was accidentally initialized upside down (while carrying the drone for example). You can set it to false and if there's a mismatch on VIO-PX4, you'll see it immediately.

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    hmlow
    Regular
    wrote on last edited by hmlow
    #8

    @Cliff-Wong

    While the logs and graphs above are based on my own customized aircraft, I just tried the same maneuver on the Starling (with shipped params and configured for indoor VIO) and i can confirm that the same observation is repeatable.

    Im curious if you guys would see the same uncommanded climb/sink if you would roll your own Starling aircraft left (or right) for 10 - 20m (3m/s, with CP turned off) and then in the opposite direction. The logs would also show that the EKF2 estimates having the same issues as i have described here and on the github post..

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    • H hmlow

      @Cliff-Wong

      While the logs and graphs above are based on my own customized aircraft, I just tried the same maneuver on the Starling (with shipped params and configured for indoor VIO) and i can confirm that the same observation is repeatable.

      Im curious if you guys would see the same uncommanded climb/sink if you would roll your own Starling aircraft left (or right) for 10 - 20m (3m/s, with CP turned off) and then in the opposite direction. The logs would also show that the EKF2 estimates having the same issues as i have described here and on the github post..

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      hmlow
      Regular
      wrote on last edited by
      #9

      Hi did anyone manage to verify this?

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      • H hmlow

        Hi did anyone manage to verify this?

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        hmlow
        Regular
        wrote on last edited by
        #10

        Any devs?

        I was able to produce this issue on two separate Starlings and a customized 250g drone

        wilkinsafW 1 Reply Last reply
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        • H hmlow

          Any devs?

          I was able to produce this issue on two separate Starlings and a customized 250g drone

          wilkinsafW Offline
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          wilkinsaf
          ModalAI Team
          wrote on last edited by
          #11

          @hmlow I was seeing the same thing on my starling. Have you tried completely disconnecting the GPS/baro unit on top and turning off the parameter HAS_MAG?

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          • wilkinsafW wilkinsaf

            @hmlow I was seeing the same thing on my starling. Have you tried completely disconnecting the GPS/baro unit on top and turning off the parameter HAS_MAG?

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            hmlow
            Regular
            wrote on last edited by
            #12

            @wilkinsaf That solved the issue for you?

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            • H hmlow

              @wilkinsaf That solved the issue for you?

              wilkinsafW Offline
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              wilkinsaf
              ModalAI Team
              wrote on last edited by
              #13

              @hmlow yes. Ideally you would adjust the EKF2 parameters to increase the gps/mag threshold so they wouldn't affect your local position. But, quick and dirty is to unplug the gps unit. See if that solves your issue. If it does, then worry about EKF2 parameters

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              • wilkinsafW wilkinsaf

                @hmlow yes. Ideally you would adjust the EKF2 parameters to increase the gps/mag threshold so they wouldn't affect your local position. But, quick and dirty is to unplug the gps unit. See if that solves your issue. If it does, then worry about EKF2 parameters

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                hmlow
                Regular
                wrote on last edited by
                #14

                @wilkinsaf actually no, I'm using neither GPS nor mag (disabled both) as my flights are entirely indoors

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                • H hmlow

                  @wilkinsaf actually no, I'm using neither GPS nor mag (disabled both) as my flights are entirely indoors

                  wilkinsafW Offline
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                  wilkinsaf
                  ModalAI Team
                  wrote on last edited by
                  #15

                  @hmlow

                  So, basically the main issue is that in the logs the qvio and ekf2 are reporting different position estimates? But, everything is flying correctly?

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                  • wilkinsafW wilkinsaf

                    @hmlow

                    So, basically the main issue is that in the logs the qvio and ekf2 are reporting different position estimates? But, everything is flying correctly?

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                    hmlow
                    Regular
                    wrote on last edited by hmlow
                    #16

                    @wilkinsaf Flying correctly for the most part yes.

                    Except during specific maneuvers as i have described in my first post (details in the github link) and the third post.
                    Its challenging to summarize the issue in a few lines..

                    wilkinsafW 1 Reply Last reply
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                    • H hmlow

                      @wilkinsaf Flying correctly for the most part yes.

                      Except during specific maneuvers as i have described in my first post (details in the github link) and the third post.
                      Its challenging to summarize the issue in a few lines..

                      wilkinsafW Offline
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                      wilkinsaf
                      ModalAI Team
                      wrote on last edited by
                      #17

                      @hmlow I was flying over the weekend, and saw some inconsistencies as well tbh. The quality of the QVIO was reporting not as high as it was in version 0.9.5 SDK release. I will ask the devs and see what they say.
                      First, I need to compile some logs from voxl-qvio.

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