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  3. QGC sensors - compass remains red

QGC sensors - compass remains red

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  • S suvasis

    hi Eric,
    I connected using wifi. /usr/bin/voxl-px4 is the command I am using.

    Can you point me to the documentation? Also should I use usbc only and not wifi?

    Thanks.
    suvasis

    Eric KatzfeyE Offline
    Eric KatzfeyE Offline
    Eric Katzfey
    ModalAI Team
    wrote on last edited by
    #9

    @suvasis /usr/bin/voxl-px4 is a bash script and has some inline documentation. It relies on the startup configuration script /etc/modalai/voxl-px4.config which also has some inline documentation.

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    • S suvasis

      hi Eric,
      I connected using wifi. /usr/bin/voxl-px4 is the command I am using.

      Can you point me to the documentation? Also should I use usbc only and not wifi?

      Thanks.
      suvasis

      Eric KatzfeyE Offline
      Eric KatzfeyE Offline
      Eric Katzfey
      ModalAI Team
      wrote on last edited by
      #10

      @suvasis For magnetometer rotation it is specified as the -R option on the start line in /etc/modalai/voxl-px4.config. For example: qshell ist8310 start -R 10 -X -b 1 has a rotation specified by the -R option. This is from the standard PX4 documentation.

      Abdullah01A 1 Reply Last reply
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      • S Offline
        S Offline
        suvasis
        Contributor
        wrote on last edited by
        #11

        hi Eric

        For magnetometer rotation it is specified as the -R option on the start line in /etc/modalai/voxl-px4.config

        IS it the magnetometer not an inherent part of the VOXL2 board? Is it part of GPS? I have not attached GPS to my drone yet, For compass do I need GPS?
        Thanks.
        suvasis

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        • S Offline
          S Offline
          suvasis
          Contributor
          wrote on last edited by
          #12

          hi Eric,
          I have not hooked up the GPS to my vehicle.

          I run the following commands:

          (do't see magnetometer anywhere)
          voxl2:~$ sudo journalctl -u voxl-px4 -f

          -- Logs begin at Tue 2022-09-06 03:18:07 UTC. --
          Mar 21 17:49:39 m0054 bash[1748]: INFO [muorb] SLPI: Advertising remote topic vehicle_command
          Mar 21 17:49:39 m0054 bash[1748]: INFO [commander] Handling Commander command 176
          Mar 21 17:49:39 m0054 bash[1748]: INFO [muorb] SLPI: Advertising remote topic vehicle_command_ack
          Mar 21 17:49:39 m0054 bash[1748]: INFO [mavlink] mode: Onboard, data rate: 100000 B/s on udp port 14556 remote port 14557
          Mar 21 17:49:39 m0054 bash[1748]: INFO [muorb] SLPI: Marking DeviceNode(vehicle_command) as advertised in process_remote_topic
          Mar 21 17:49:39 m0054 bash[1748]: INFO [px4] Startup script returned successfully
          Mar 21 17:49:39 m0054 bash[1748]: INFO [mavlink] partner IP: 127.0.0.1
          Mar 21 17:49:39 m0054 bash[1748]: INFO [muorb] SLPI: Advertising remote topic telemetry_status
          Mar 21 17:49:39 m0054 bash[1748]: INFO [PreFlightCheck] Failed EKF health preflight check while waiting for filter to settle
          Mar 21 17:49:39 m0054 bash[1748]: INFO [muorb] SLPI: Advertising remote topic timesync_status

          and

          (also don't see any address)
          voxl2:~$ sudo i2cdetect -y -r 1
          0 1 2 3 4 5 6 7 8 9 a b c d e f
          00: -- -- -- -- -- -- -- -- -- -- -- -- --
          10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
          20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
          30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
          40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
          50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
          60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
          70: -- -- -- -- -- -- -- --

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          • Chad SweetC Offline
            Chad SweetC Offline
            Chad Sweet
            ModalAI Team
            wrote on last edited by
            #13

            There is no magnetometer on VOXL 2, you need to connect the GPS unit that includes the magnetometer

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            • S Offline
              S Offline
              suvasis
              Contributor
              wrote on last edited by
              #14

              Thankyou Chris, looks like QGC estimated heading information derived from other sensors, like the gyroscope and accelerometer, rather than a magnetometer. I got false idea from QGC.

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              • Eric KatzfeyE Eric Katzfey

                @suvasis For magnetometer rotation it is specified as the -R option on the start line in /etc/modalai/voxl-px4.config. For example: qshell ist8310 start -R 10 -X -b 1 has a rotation specified by the -R option. This is from the standard PX4 documentation.

                Abdullah01A Offline
                Abdullah01A Offline
                Abdullah01
                Contributor
                wrote on last edited by
                #15

                @Eric-Katzfey said in QGC sensors - compass remains red:

                qshell ist8310 start

                Thank you.

                So, if my GPS is in the opposite orientation of the voxl imu by Yaw 180 deg, so I need to change it form 10 to (4), right?

                Eric KatzfeyE 1 Reply Last reply
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                • Abdullah01A Abdullah01

                  @Eric-Katzfey said in QGC sensors - compass remains red:

                  qshell ist8310 start

                  Thank you.

                  So, if my GPS is in the opposite orientation of the voxl imu by Yaw 180 deg, so I need to change it form 10 to (4), right?

                  Eric KatzfeyE Offline
                  Eric KatzfeyE Offline
                  Eric Katzfey
                  ModalAI Team
                  wrote on last edited by
                  #16

                  @Abdullah01 The IMU rotation is handled separately. For the magnetometer in a Holybro GPS unit the rotation is specified as 10 (roll 180, yaw 90) when the unit is mounted on the drone with the arrow pointing towards to front of the drone. If you reverse this and the arrow points to the rear of the drone then you would specify 14 (roll 180, yaw 270).

                  Abdullah01A 1 Reply Last reply
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                  • Eric KatzfeyE Eric Katzfey

                    @Abdullah01 The IMU rotation is handled separately. For the magnetometer in a Holybro GPS unit the rotation is specified as 10 (roll 180, yaw 90) when the unit is mounted on the drone with the arrow pointing towards to front of the drone. If you reverse this and the arrow points to the rear of the drone then you would specify 14 (roll 180, yaw 270).

                    Abdullah01A Offline
                    Abdullah01A Offline
                    Abdullah01
                    Contributor
                    wrote on last edited by Abdullah01
                    #17

                    @Eric-Katzfey said in QGC sensors - compass remains red:

                    mounted on the drone with the arrow pointing towards to front of the drone. If you reverse this and the arrow points to the rear of the drone then you would specify 14 (roll 180, yaw 270).

                    Ok, that means our config file is correct.

                    During the sensor calibration for the accelerometer shows an error in the orientation error pic showsWhatsApp Image 2023-06-13 at 2.19.53 PM.jpeg here

                    Also, for the compass calibration, once I restart the drone after finishing the calibration it goes away and I need to calibrate it again.

                    BTW, the voxl orientation is different than the GPS., and changed the config file to rotate the voxl orientation. Do think this might be the issue?

                    You can see this in the drone setup below, where the original orientation of the voxl is opposite to the drone's front

                    WhatsApp Image 2023-06-14 at 2.47.49 PM Medium.jpeg

                    So, what do you think is the issue? Also, we are using I/O Board do think it needs a different setup?

                    Thank you for your support

                    Eric KatzfeyE 1 Reply Last reply
                    0
                    • Abdullah01A Abdullah01

                      @Eric-Katzfey said in QGC sensors - compass remains red:

                      mounted on the drone with the arrow pointing towards to front of the drone. If you reverse this and the arrow points to the rear of the drone then you would specify 14 (roll 180, yaw 270).

                      Ok, that means our config file is correct.

                      During the sensor calibration for the accelerometer shows an error in the orientation error pic showsWhatsApp Image 2023-06-13 at 2.19.53 PM.jpeg here

                      Also, for the compass calibration, once I restart the drone after finishing the calibration it goes away and I need to calibrate it again.

                      BTW, the voxl orientation is different than the GPS., and changed the config file to rotate the voxl orientation. Do think this might be the issue?

                      You can see this in the drone setup below, where the original orientation of the voxl is opposite to the drone's front

                      WhatsApp Image 2023-06-14 at 2.47.49 PM Medium.jpeg

                      So, what do you think is the issue? Also, we are using I/O Board do think it needs a different setup?

                      Thank you for your support

                      Eric KatzfeyE Offline
                      Eric KatzfeyE Offline
                      Eric Katzfey
                      ModalAI Team
                      wrote on last edited by
                      #18

                      @Abdullah01 Looks like it is the IMU rotation that isn't being specified correctly. It's kind of hard to tell in the picture but, at a minimum, the board is rotated 180 degrees. So it's the IMU rotation that needs to be set.

                      Abdullah01A 1 Reply Last reply
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                      • Eric KatzfeyE Eric Katzfey

                        @Abdullah01 Looks like it is the IMU rotation that isn't being specified correctly. It's kind of hard to tell in the picture but, at a minimum, the board is rotated 180 degrees. So it's the IMU rotation that needs to be set.

                        Abdullah01A Offline
                        Abdullah01A Offline
                        Abdullah01
                        Contributor
                        wrote on last edited by
                        #19

                        @Eric-Katzfey said in QGC sensors - compass remains red:

                        t isn't being specified correctly. It's kind of hard to tell in the picture but, at a minimum, the board is rotated 180 degrees. So it's the IMU rotation that needs to be set.

                        yes, the board is rotated 180 degrees. So, how do I set the rotation of the IMU to 180 degrees? is it in the same config file?

                        I rotate it 180 degrees as shown below

                        AAAA.png

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