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  3. April Tag Relocalization with External Fight Controller

April Tag Relocalization with External Fight Controller

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  • A Offline
    A Offline
    afdrus
    Regular
    wrote on last edited by
    #1

    Hi everyone,
    I am trying to use the April Tag Relocalization with an External Flight Controller. Everything works fine on the voxel's side i.e. the tag is detected and my debugging show that the body frame with respect to the fixed frame is computed correctly. However, it is unclear to me how the correction of the April Tag is transmitted to the autopilot since the documentation says:

    "When enabled, any SET_POSITION_TARGET_LOCAL_NED mavlink messages received through UDP will have its position, velocity, acceleration, and yaw values updated with the fixed frame offset before being sent to PX4 over UART. This is very useful for MAVROS and MAVSDK processes running locally or remotely."

    I was expecting this to work also with an external flight controller by sending the setpoints from a remote ground station, but the drone keeps NOT following the tag's corrections. Could you provide some help with this issue?

    Thanks in advance for your response.

    A 1 Reply Last reply
    0
    • A afdrus

      Hi everyone,
      I am trying to use the April Tag Relocalization with an External Flight Controller. Everything works fine on the voxel's side i.e. the tag is detected and my debugging show that the body frame with respect to the fixed frame is computed correctly. However, it is unclear to me how the correction of the April Tag is transmitted to the autopilot since the documentation says:

      "When enabled, any SET_POSITION_TARGET_LOCAL_NED mavlink messages received through UDP will have its position, velocity, acceleration, and yaw values updated with the fixed frame offset before being sent to PX4 over UART. This is very useful for MAVROS and MAVSDK processes running locally or remotely."

      I was expecting this to work also with an external flight controller by sending the setpoints from a remote ground station, but the drone keeps NOT following the tag's corrections. Could you provide some help with this issue?

      Thanks in advance for your response.

      A Offline
      A Offline
      afdrus
      Regular
      wrote on last edited by
      #2

      I was able to make it work. I have only one question left: is it possible to leverage the Relocalization only in Offboard mode and not in Mission? Or am I missing something?

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      • A afdrus

        I was able to make it work. I have only one question left: is it possible to leverage the Relocalization only in Offboard mode and not in Mission? Or am I missing something?

        A Offline
        A Offline
        afdrus
        Regular
        wrote on last edited by
        #3

        To conclude this post in the hope to help someone else who's having the same problem, I found this reply on another question in this forum which dates back to 2021. I guess the Relocalization still works only in Offboard and NOT in Mission. The same applies for an external flight controller e.g. in Ardupilot it works in Guided Mode and NOT in Auto.

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