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MAVSDK Python Example Hanging

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  • K Offline
    K Offline
    kiprock
    Contributor
    wrote on last edited by
    #1

    Hello! I tried the MAVSDK python example this afternoon and it looks like it's hanging while waiting for global position estimate:

    root@apq8096:/home# python3 takeoff_and_land2.py
    Waiting for mavsdk_server to be ready...
    Connected to mavsdk_server!
    Waiting for drone to connect...
    Drone discovered with UUID: 3762846593019032885
    Waiting for drone to have a global position estimate...
    

    Suggestions for debugging?

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    • modaltbM Offline
      modaltbM Offline
      modaltb
      ModalAI Team
      wrote on last edited by
      #2

      Hey Kip,

      I'm guessing you have GPS lock right? You can see this if you have QGC connected, there's a little satellite icon on the top bar.

      To be honest I think it could be commented out, this was a copy/pasta from the MAVSDK examples.

      For your use case we discussed, here's another example that should be in the container as well, showing how to set the "waypoints" using VIO:

      Link Preview Image
      offboard_position_ned2.py · master · voxl / VOXL Docker Images / voxl-docker-mavsdk-python · GitLab

      Example of how to use MAVSDK Python in a Docker container running on target.

      favicon

      GitLab (gitlab.com)

      Here's the video for that one as reference (NOTE: the April Tag in the video isn't being used. BUT, this is a good example of how you could configure april tags on the ground and program their locations. Then during this flight, the m500 could do a course correction if needed for higher accuracy). https://www.youtube.com/watch?v=V3vVs8fEOZs

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      • K Offline
        K Offline
        kiprock
        Contributor
        wrote on last edited by
        #3

        QGC says "No GPS Lock for Vehicle" and gps status is set to 0.

        I'm having another strange problem that might be related... when trying to run voxl-vision-px4 the system is crashing entirely.

        ~ # voxl-vision-px4 --debug_fixed_frame
        loading config file
        =================================================================
        Parameters as loaded from config file:
        qgc_ip:                     192.168.0.218
        en_localhost_mavlink_udp    1
        en_secondary_qgc:           0
        secondary_qgc_ip:           192.168.1.214
        en_vio:                     1
        en_voa:                     0
        en_send_vio_to_qgc:         0
        en_send_voa_to_qgc:         0
        en_adsb:                    0
        adsb_uart_bus:              7
        adsb_uart_baudrate:         57600
        px4_uart_bus:               5
        px4_uart_baudrate:          921600
        offboard_mode:              off
        R_imu_to_body:
         0.0000   1.0000   0.0000
         1.0000   0.0000   0.0000
         0.0000   0.0000  -1.0000
        T_imu_wrt_body:
         0.0680  -0.0150  -0.0080
        height_body_above_ground_m:  0.050
        land_on_tag_id:             0
        follow_tag_id:              0
        en_apriltag_fixed_frame:    1
        en_transform_mavlink_pos_setpoints_from_fixed_frame:1
        n_fixed_apriltags:          1
        Fixed apriltag #0:
            tag id: 0
            R_tag_to_fixed:
         0.0000  -1.0000   0.0000
         1.0000   0.0000   0.0000
         0.0000   0.0000   1.0000
            T_tag_wrt_fixed:
         0.0000   0.0000   0.0000
        
        T_stereo_wrt_body:
         0.1000  -0.0400   0.0000
        en_fixed_frame_pipe:        0
        fixed_frame_filter_len:     5
        =================================================================
        WARNING, exising instance of voxl-vision-px4 found, attempting to stop it
        starting geometry module
        starting uart mavlink
        
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        • K Offline
          K Offline
          kiprock
          Contributor
          wrote on last edited by kiprock
          #4

          The flight computer doesn't seem to be getting any positional data for some reason. Is this normal? (see the last line below)

          ~ # systemctl restart voxl-vision-px4
          ~ #
          ~ #
          ~ # systemctl status voxl-vision-px4
          ● voxl-vision-px4.service - voxl-vision-px4
             Loaded: loaded (/usr/bin/voxl-vision-px4; enabled; vendor preset: enabled)
             Active: active (running) since Sat 2021-04-03 00:11:47 UTC; 5s ago
           Main PID: 4007 (voxl-vision-px4)
             CGroup: /system.slice/voxl-vision-px4.service
                     └─4007 /usr/bin/voxl-vision-px4
          
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: LNX_8074 supported? 1
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: LNX_8096 supported? 1
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: LNX_IA64 supported? 1
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: WINDOWS supported? 0
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: FASTCV: fcvAvailableHardware Linux
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: FASTCV: fcvAvailableHardware Linux
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: [146.135049] SNAV INFO: CameraManager is finished initializing.
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: [146.135099] SNAV INFO: Starting camera image streaming...
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: [146.146347] SNAV ERROR: Error starting camera streaming. Exiting.
          Apr 03 00:11:47 apq8096 voxl-vision-px4[4007]: ERROR: failed to start modalai vision lib
          
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          • modaltbM Offline
            modaltbM Offline
            modaltb
            ModalAI Team
            wrote on last edited by
            #5

            Hey @kiprock ,

            Checking in with ya, we had a side email going and I believe getting the camera configuration setup got voxl-vision-px4 going.

            Were you able to get a GPS signal going? Depending on the reception, we sometimes need to move outside of our building to pickup satellites.

            Thanks!

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            • K Offline
              K Offline
              kiprock
              Contributor
              wrote on last edited by
              #6

              I was able to resolve. I had been following the ModalAI Vision Lib documentation and selected the wrong camera configuration, which causes failures and problems with the core voxl-vision software. The default is #1, but the m500 is #3 (hires + stereo + tracking). Problem solved. Thanks!

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              • Chad SweetC Offline
                Chad SweetC Offline
                Chad Sweet
                ModalAI Team
                wrote on last edited by
                #7

                Good news. We will get that updated to be a little more clear.

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