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  4. QGC Starts up showing a heading of north no mater the direction of compass

QGC Starts up showing a heading of north no mater the direction of compass

Scheduled Pinned Locked Moved VOXL 2
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  • Eric KatzfeyE Eric Katzfey

    @Chase-Riley It makes me believe that one of the rotations somewhere is not set correctly. What is SENS_BOARD_ROT set to? I guess we can just trace the topic messages through the system to see where it is getting confused. So you already did listener sensor_mag and you can see it publishing and the values updating regularly when you move the unit around? That topic goes to the sensors module that then publishes the vehicle_magnetometer topic. Can you do a listener on that to make sure it looks like it is working?

    Chase RileyC Offline
    Chase RileyC Offline
    Chase Riley
    Regular
    wrote on last edited by
    #21

    @Eric-Katzfey running px4-listener sensor_mag shows the mag data and it changes as I move the GPS/Mag around. So that is behaving how I would expect it to SENS_BOARD_ROT is set to YAW 180. This is due to the VOXL2 being mounted 180 degrees rotated in the air frame.

    Everything seems to go well through an compass calibration. We have done quite a few while troubleshooting this.

    I will take a look at the failsafes when I try to go into position mode, however at this point I think the heading needs to be resolved first either way. Am I correct to think that when rotating the GPS/Mag separate from the VOXL2 I should see a heading change based on the direction of the GPS/Mag? In this case I only see the heading change when rotating the VOXL2 (Which to my knowledge has no Mag on board).

    Eric KatzfeyE 2 Replies Last reply
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    • Chase RileyC Chase Riley

      @Eric-Katzfey running px4-listener sensor_mag shows the mag data and it changes as I move the GPS/Mag around. So that is behaving how I would expect it to SENS_BOARD_ROT is set to YAW 180. This is due to the VOXL2 being mounted 180 degrees rotated in the air frame.

      Everything seems to go well through an compass calibration. We have done quite a few while troubleshooting this.

      I will take a look at the failsafes when I try to go into position mode, however at this point I think the heading needs to be resolved first either way. Am I correct to think that when rotating the GPS/Mag separate from the VOXL2 I should see a heading change based on the direction of the GPS/Mag? In this case I only see the heading change when rotating the VOXL2 (Which to my knowledge has no Mag on board).

      Eric KatzfeyE Offline
      Eric KatzfeyE Offline
      Eric Katzfey
      ModalAI Team
      wrote on last edited by
      #22

      @Chase-Riley Instead of setting SENS_BOARD_ROT you can set the rotation on the IMU driver to -R 4. But don't do both. I would try setting SENS_BOARD_ROT to 0 and keeping the -R 4 on the IMU driver start and see if that makes any difference. Also, do the listener vehicle_magnetometer to see if it is updating nicely like listener sensor_mag does.

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      • Chase RileyC Chase Riley

        @Eric-Katzfey running px4-listener sensor_mag shows the mag data and it changes as I move the GPS/Mag around. So that is behaving how I would expect it to SENS_BOARD_ROT is set to YAW 180. This is due to the VOXL2 being mounted 180 degrees rotated in the air frame.

        Everything seems to go well through an compass calibration. We have done quite a few while troubleshooting this.

        I will take a look at the failsafes when I try to go into position mode, however at this point I think the heading needs to be resolved first either way. Am I correct to think that when rotating the GPS/Mag separate from the VOXL2 I should see a heading change based on the direction of the GPS/Mag? In this case I only see the heading change when rotating the VOXL2 (Which to my knowledge has no Mag on board).

        Eric KatzfeyE Offline
        Eric KatzfeyE Offline
        Eric Katzfey
        ModalAI Team
        wrote on last edited by
        #23

        @Chase-Riley Is there any way that you can orient the board exactly as we have it in one of our drones (Sentinel, Starling) and use our parameter set and see if it works fine then?

        Chase RileyC 3 Replies Last reply
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        • Eric KatzfeyE Eric Katzfey

          @Chase-Riley Is there any way that you can orient the board exactly as we have it in one of our drones (Sentinel, Starling) and use our parameter set and see if it works fine then?

          Chase RileyC Offline
          Chase RileyC Offline
          Chase Riley
          Regular
          wrote on last edited by
          #24

          @Eric-Katzfey I set SENS_BOARD_ROT to No rotation and made the change to the IMU driver as you mentioned and had the same results still always points north on startup. px4-listener vehicle_magnetometer updates nicely as just like px4-listener sensor_mag.

          I was able to flash the sentinel params on to the board and was able to match the orientation of the Sentinel and had the same results. I made sure to change the IMU driver back to original before this test.

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          • Eric KatzfeyE Eric Katzfey

            @Chase-Riley Is there any way that you can orient the board exactly as we have it in one of our drones (Sentinel, Starling) and use our parameter set and see if it works fine then?

            Chase RileyC Offline
            Chase RileyC Offline
            Chase Riley
            Regular
            wrote on last edited by
            #25

            @Eric-Katzfey I went back in this morning and flashed the ci_sentinel-params which seems to be a entire param set and was able to get it working. Now I need to change the VOXL2 orientation. Would you recomend doing this through QGC or the voxl-px4-start? I am unsure which parameter caused it to start to work. Any insight would be appreciated so that I can make that change in my other systems with out having to change a bunch of params.

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            • Eric KatzfeyE Eric Katzfey

              @Chase-Riley Is there any way that you can orient the board exactly as we have it in one of our drones (Sentinel, Starling) and use our parameter set and see if it works fine then?

              Chase RileyC Offline
              Chase RileyC Offline
              Chase Riley
              Regular
              wrote on last edited by
              #26

              @Eric-Katzfey I pulled the params from the system I have working and one of the systems that is having the Mag problem. Weirdly enough there is only 9 differences. I have listed them below. They all seem to be calibration differences if I understand correctly.

              CAL_ACC0_XOFF
              CAL_ACC0_YOFF
              CAL_ACC0_ZOFF

              CAL_GYRO0_XOFF
              CAL_GYRO0_YOFF
              CAL_GYRO0_ZOFF

              CAL_MAG0_XSCALE
              CAL_MAG0_YSCALE
              CAL_MAG0_ZSCALE

              Eric KatzfeyE 1 Reply Last reply
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              • Chase RileyC Chase Riley

                @Eric-Katzfey I pulled the params from the system I have working and one of the systems that is having the Mag problem. Weirdly enough there is only 9 differences. I have listed them below. They all seem to be calibration differences if I understand correctly.

                CAL_ACC0_XOFF
                CAL_ACC0_YOFF
                CAL_ACC0_ZOFF

                CAL_GYRO0_XOFF
                CAL_GYRO0_YOFF
                CAL_GYRO0_ZOFF

                CAL_MAG0_XSCALE
                CAL_MAG0_YSCALE
                CAL_MAG0_ZSCALE

                Eric KatzfeyE Offline
                Eric KatzfeyE Offline
                Eric Katzfey
                ModalAI Team
                wrote on last edited by
                #27

                @Chase-Riley Huh, that's very interesting. I'm guessing that if the rotation isn't set properly and a calibration is done then those calibration parameters will be incorrect such that even when all rotations are specified correctly those old calibration values will mess everything up. So I guess that each time any rotation parameter or option is changed you need to go and recalibrate everything. For your case it seems like you should leave everything the same as Sentinel except change the rotation of the IMU driver in voxl-px4-start to -R 4 and then recalibrate everything.

                Chase RileyC 1 Reply Last reply
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                • Eric KatzfeyE Eric Katzfey

                  @Chase-Riley Huh, that's very interesting. I'm guessing that if the rotation isn't set properly and a calibration is done then those calibration parameters will be incorrect such that even when all rotations are specified correctly those old calibration values will mess everything up. So I guess that each time any rotation parameter or option is changed you need to go and recalibrate everything. For your case it seems like you should leave everything the same as Sentinel except change the rotation of the IMU driver in voxl-px4-start to -R 4 and then recalibrate everything.

                  Chase RileyC Offline
                  Chase RileyC Offline
                  Chase Riley
                  Regular
                  wrote on last edited by
                  #28

                  @Eric-Katzfey It is interesting. I was able to get this working on SDK 1.1.2. This morning I tried to follow the same procedure with one of my SDK 1.0 systems and have had no luck. I reflashed the sentinel params and changed the rotations back to factory just like I did on the SDK 1.1.2 system and had no luck. I am guessing next steps at this point will be to upgrade my SDK 1.0 system to SDK 1.1.2 and see if the issue is solved.

                  Eric KatzfeyE 1 Reply Last reply
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                  • Chase RileyC Chase Riley

                    @Eric-Katzfey It is interesting. I was able to get this working on SDK 1.1.2. This morning I tried to follow the same procedure with one of my SDK 1.0 systems and have had no luck. I reflashed the sentinel params and changed the rotations back to factory just like I did on the SDK 1.1.2 system and had no luck. I am guessing next steps at this point will be to upgrade my SDK 1.0 system to SDK 1.1.2 and see if the issue is solved.

                    Eric KatzfeyE Offline
                    Eric KatzfeyE Offline
                    Eric Katzfey
                    ModalAI Team
                    wrote on last edited by
                    #29

                    @Chase-Riley Definitely would recommend being on 1.1.2 at this point.

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