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Outdoor navigation GPS problem

Scheduled Pinned Locked Moved Qualcomm Flight RB5 5G Drone
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  • V Offline
    V Offline
    vjuliani
    Contributor
    wrote on last edited by
    #1

    The issue is similar to the https://forum.modalai.com/topic/3410/outdoor-navigation-problem one.

    When I try an outdoor flight in position mode using EKF2_GPS_CHECK to 245, QGC shows a lot of GPS Speed Accuracy too low failure messages. With that, the drone status remains in Not Ready and it can't fly.

    If I try to set EKF2_GPS_CHECK to 1, I get Pre-flight check failure: GPS Position Required messages from QGC. So, the status remains in Not Ready and the drone can't fly.

    The only manner I found the drone flight to work was to set COM_ARM_WO_GPS to 1 and use altitude or manual flight mode.

    I think it might be a gps hardware issue, like the one in the topic linked above.

    The GPS model I had is M8N and I already had this issue with VOXL SDK 0.9.5.

    Any suggestions?

    ModeratorM Eric KatzfeyE 2 Replies Last reply
    0
    • V vjuliani referenced this topic on
    • V vjuliani

      The issue is similar to the https://forum.modalai.com/topic/3410/outdoor-navigation-problem one.

      When I try an outdoor flight in position mode using EKF2_GPS_CHECK to 245, QGC shows a lot of GPS Speed Accuracy too low failure messages. With that, the drone status remains in Not Ready and it can't fly.

      If I try to set EKF2_GPS_CHECK to 1, I get Pre-flight check failure: GPS Position Required messages from QGC. So, the status remains in Not Ready and the drone can't fly.

      The only manner I found the drone flight to work was to set COM_ARM_WO_GPS to 1 and use altitude or manual flight mode.

      I think it might be a gps hardware issue, like the one in the topic linked above.

      The GPS model I had is M8N and I already had this issue with VOXL SDK 0.9.5.

      Any suggestions?

      ModeratorM Offline
      ModeratorM Offline
      Moderator
      ModalAI Team
      wrote on last edited by
      #2

      @vjuliani Can you lower the error threshold a bit?

      1 Reply Last reply
      0
      • V vjuliani

        The issue is similar to the https://forum.modalai.com/topic/3410/outdoor-navigation-problem one.

        When I try an outdoor flight in position mode using EKF2_GPS_CHECK to 245, QGC shows a lot of GPS Speed Accuracy too low failure messages. With that, the drone status remains in Not Ready and it can't fly.

        If I try to set EKF2_GPS_CHECK to 1, I get Pre-flight check failure: GPS Position Required messages from QGC. So, the status remains in Not Ready and the drone can't fly.

        The only manner I found the drone flight to work was to set COM_ARM_WO_GPS to 1 and use altitude or manual flight mode.

        I think it might be a gps hardware issue, like the one in the topic linked above.

        The GPS model I had is M8N and I already had this issue with VOXL SDK 0.9.5.

        Any suggestions?

        Eric KatzfeyE Offline
        Eric KatzfeyE Offline
        Eric Katzfey
        ModalAI Team
        wrote on last edited by
        #3

        @vjuliani So if you change EKF2_GPS_CHECK to 1 then it is only looking at number of satellites as a quality metric. But it seems you are still not able to arm unless you allow arming without any GPS. Can you arm and do a manual flight and then attach the log from the flight here? Are you trying this outdoors with a clear unobstructed view to the sky?

        1 Reply Last reply
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        • V Offline
          V Offline
          vjuliani
          Contributor
          wrote on last edited by
          #4

          @Moderator Yes, how can I do that?

          @Eric-Katzfey, yes I am trying outdoors. I am even waiting more than 10 minutes too see if the GPS locks but it doesnt

          IMG_20240710_151704497.jpg

          Here are the logs of two of the outdoor flight attempts with manual flight mode: https://www.mediafire.com/folder/qhidipn0n1xng/RB5-outdoor-flight-logs

          When I tried the outdoor flights with manual flight mode, one of the drone's rotors seemed to not be working properly. You can see it in this video: https://www.youtube.com/watch?v=F7ug6u2W8Yw

          Is there any PX4 parameter I could change in order to try to fix it?

          It happened after upgrading from VOXL SDK 0.9.5 to 1.1.2...

          Thanks in advance!

          Eric KatzfeyE 4 Replies Last reply
          0
          • V vjuliani

            @Moderator Yes, how can I do that?

            @Eric-Katzfey, yes I am trying outdoors. I am even waiting more than 10 minutes too see if the GPS locks but it doesnt

            IMG_20240710_151704497.jpg

            Here are the logs of two of the outdoor flight attempts with manual flight mode: https://www.mediafire.com/folder/qhidipn0n1xng/RB5-outdoor-flight-logs

            When I tried the outdoor flights with manual flight mode, one of the drone's rotors seemed to not be working properly. You can see it in this video: https://www.youtube.com/watch?v=F7ug6u2W8Yw

            Is there any PX4 parameter I could change in order to try to fix it?

            It happened after upgrading from VOXL SDK 0.9.5 to 1.1.2...

            Thanks in advance!

            Eric KatzfeyE Offline
            Eric KatzfeyE Offline
            Eric Katzfey
            ModalAI Team
            wrote on last edited by
            #5

            @vjuliani The log shows a 3D GPS lock with 14 satellites.

            1 Reply Last reply
            0
            • V vjuliani

              @Moderator Yes, how can I do that?

              @Eric-Katzfey, yes I am trying outdoors. I am even waiting more than 10 minutes too see if the GPS locks but it doesnt

              IMG_20240710_151704497.jpg

              Here are the logs of two of the outdoor flight attempts with manual flight mode: https://www.mediafire.com/folder/qhidipn0n1xng/RB5-outdoor-flight-logs

              When I tried the outdoor flights with manual flight mode, one of the drone's rotors seemed to not be working properly. You can see it in this video: https://www.youtube.com/watch?v=F7ug6u2W8Yw

              Is there any PX4 parameter I could change in order to try to fix it?

              It happened after upgrading from VOXL SDK 0.9.5 to 1.1.2...

              Thanks in advance!

              Eric KatzfeyE Offline
              Eric KatzfeyE Offline
              Eric Katzfey
              ModalAI Team
              wrote on last edited by
              #6

              @vjuliani Your GPS location from the log: https://www.google.com/maps/place/22°48'54.2"S+47°02'48.1"W/@-22.8154809,-47.0471945,1108m/data=!3m1!1e3!4m4!3m3!8m2!3d-22.8150558!4d-47.0466938?entry=ttu

              1 Reply Last reply
              0
              • V vjuliani

                @Moderator Yes, how can I do that?

                @Eric-Katzfey, yes I am trying outdoors. I am even waiting more than 10 minutes too see if the GPS locks but it doesnt

                IMG_20240710_151704497.jpg

                Here are the logs of two of the outdoor flight attempts with manual flight mode: https://www.mediafire.com/folder/qhidipn0n1xng/RB5-outdoor-flight-logs

                When I tried the outdoor flights with manual flight mode, one of the drone's rotors seemed to not be working properly. You can see it in this video: https://www.youtube.com/watch?v=F7ug6u2W8Yw

                Is there any PX4 parameter I could change in order to try to fix it?

                It happened after upgrading from VOXL SDK 0.9.5 to 1.1.2...

                Thanks in advance!

                Eric KatzfeyE Offline
                Eric KatzfeyE Offline
                Eric Katzfey
                ModalAI Team
                wrote on last edited by
                #7

                @vjuliani So, the GPS seems to be working okay. It's not clear why you cannot get a global position in PX4 using that data. Let me look through the parameters and see if I can suggest some others to change.

                Eric KatzfeyE 1 Reply Last reply
                0
                • V vjuliani

                  @Moderator Yes, how can I do that?

                  @Eric-Katzfey, yes I am trying outdoors. I am even waiting more than 10 minutes too see if the GPS locks but it doesnt

                  IMG_20240710_151704497.jpg

                  Here are the logs of two of the outdoor flight attempts with manual flight mode: https://www.mediafire.com/folder/qhidipn0n1xng/RB5-outdoor-flight-logs

                  When I tried the outdoor flights with manual flight mode, one of the drone's rotors seemed to not be working properly. You can see it in this video: https://www.youtube.com/watch?v=F7ug6u2W8Yw

                  Is there any PX4 parameter I could change in order to try to fix it?

                  It happened after upgrading from VOXL SDK 0.9.5 to 1.1.2...

                  Thanks in advance!

                  Eric KatzfeyE Offline
                  Eric KatzfeyE Offline
                  Eric Katzfey
                  ModalAI Team
                  wrote on last edited by
                  #8

                  @vjuliani Can you please open a separate forum post for the drone not flying properly? Let's keep this one for the GPS issue only. Thanks!

                  1 Reply Last reply
                  0
                  • Eric KatzfeyE Eric Katzfey

                    @vjuliani So, the GPS seems to be working okay. It's not clear why you cannot get a global position in PX4 using that data. Let me look through the parameters and see if I can suggest some others to change.

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

                    @Eric-Katzfey You can try setting EKF2_GPS_CHECK back to the default 245 value. Then experiment with the various GPS thresholds to see if you can increase any of them to get the drone to go into position mode. The relevant parameters are:

                    Maximum allowed PDOP set by EKF2_REQ_PDOP
                    Maximum allowed horizontal position error set by EKF2_REQ_EPH
                    Maximum allowed vertical position error set by EKF2_REQ_EPV
                    Maximum allowed speed error set by EKF2_REQ_SACC
                    Maximum allowed horizontal position rate set by EKF2_REQ_HDRIFT. This check will only run when the vehicle is on ground and stationary.
                    Maximum allowed vertical position rate set by EKF2_REQ_VDRIFT. This check will only run when the vehicle is on ground and stationary.
                    Maximum allowed horizontal speed set by EKF2_REQ_HDRIFT. This check will only run when the vehicle is on ground and stationary.
                    Maximum allowed vertical velocity discrepancy set by EKF2_REQ_VDRIFT

                    Eric KatzfeyE 1 Reply Last reply
                    0
                    • Eric KatzfeyE Eric Katzfey

                      @Eric-Katzfey You can try setting EKF2_GPS_CHECK back to the default 245 value. Then experiment with the various GPS thresholds to see if you can increase any of them to get the drone to go into position mode. The relevant parameters are:

                      Maximum allowed PDOP set by EKF2_REQ_PDOP
                      Maximum allowed horizontal position error set by EKF2_REQ_EPH
                      Maximum allowed vertical position error set by EKF2_REQ_EPV
                      Maximum allowed speed error set by EKF2_REQ_SACC
                      Maximum allowed horizontal position rate set by EKF2_REQ_HDRIFT. This check will only run when the vehicle is on ground and stationary.
                      Maximum allowed vertical position rate set by EKF2_REQ_VDRIFT. This check will only run when the vehicle is on ground and stationary.
                      Maximum allowed horizontal speed set by EKF2_REQ_HDRIFT. This check will only run when the vehicle is on ground and stationary.
                      Maximum allowed vertical velocity discrepancy set by EKF2_REQ_VDRIFT

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

                      @Eric-Katzfey Since it was originally complaining about speed accuracy then maybe you can increase EKF2_REQ_SACC and see if that error goes away. I do notice from the log that there is a lot of GPS noise and jamming. Not sure if that is part of the issue here though. Is there another open field in a different location that you can try as well?

                      1 Reply Last reply
                      0
                      • V vjuliani referenced this topic on
                      • V Offline
                        V Offline
                        vjuliani
                        Contributor
                        wrote on last edited by
                        #11

                        Hi @Eric-Katzfey

                        Yeah, I will try in another open field in a different location and experiment with the various GPS thresholds you mentioned. Thanks!

                        We did a site survey in the open field area we tried the flights and we got the results below: tela1.png

                        tela2.png

                        We used an AARONIA AG HyperLOG Broadband Directional antenna and a Spectrum Analyzer.

                        It might help.

                        1 Reply Last reply
                        0
                        • V Offline
                          V Offline
                          vjuliani
                          Contributor
                          wrote on last edited by vjuliani
                          #12

                          Hi @Eric-Katzfey

                          As you said, QGC and PX4 were receiving GPS data from M8N, however, EKF2 couldn't estimate the global and local valid positions.

                          After changing EKF2_MAG_TYPE, which value was as None, to Automatic, EKF2 could finished the global and local valid positions estimation and the drone became Ready to Fly with no issues from QGC.

                          So, now, after changing EKF2_REQ_SACC to 0.8m/s and EKF2_MAG_TYPE to Automatic, the drone became Ready to Fly and I could arm it using GPS.

                          Which is curious though is that here https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-px4-params/-/blob/master/params/v1.14/EKF2_helpers/outdoor_gps_baro.params in the EKF2 helper file, which I used to first configure the drone's PX4 params after upgrading from VOXL SDK 0.9.5 to 1.1.2, it says to set EKF2_MAG_TYPE to 0, so I am not sure if setting EKF2_MAG_TYPE to Automatic is the right fix, what are your thoughts? Is 0 meaning Automatic?

                          After setting EKF2_MAG_TYPE to Automatic, I tried some flights in Position Flight Mode and had the same problems of when I had tried the Manual Flight Mode flights (The one showed in the youtube video above), which @Alex-Kushleyev is helping me to figure it out in the https://forum.modalai.com/topic/3634/rb5-can-t-leave-the-ground-properly-when-flying-in-manual-flight-mode/ topic. The logs can be seen here https://www.mediafire.com/folder/jbuu2or25tjdr/position-flight-mode-logs

                          Thanks!

                          Eric KatzfeyE 1 Reply Last reply
                          0
                          • V vjuliani referenced this topic on
                          • V vjuliani

                            Hi @Eric-Katzfey

                            As you said, QGC and PX4 were receiving GPS data from M8N, however, EKF2 couldn't estimate the global and local valid positions.

                            After changing EKF2_MAG_TYPE, which value was as None, to Automatic, EKF2 could finished the global and local valid positions estimation and the drone became Ready to Fly with no issues from QGC.

                            So, now, after changing EKF2_REQ_SACC to 0.8m/s and EKF2_MAG_TYPE to Automatic, the drone became Ready to Fly and I could arm it using GPS.

                            Which is curious though is that here https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-px4-params/-/blob/master/params/v1.14/EKF2_helpers/outdoor_gps_baro.params in the EKF2 helper file, which I used to first configure the drone's PX4 params after upgrading from VOXL SDK 0.9.5 to 1.1.2, it says to set EKF2_MAG_TYPE to 0, so I am not sure if setting EKF2_MAG_TYPE to Automatic is the right fix, what are your thoughts? Is 0 meaning Automatic?

                            After setting EKF2_MAG_TYPE to Automatic, I tried some flights in Position Flight Mode and had the same problems of when I had tried the Manual Flight Mode flights (The one showed in the youtube video above), which @Alex-Kushleyev is helping me to figure it out in the https://forum.modalai.com/topic/3634/rb5-can-t-leave-the-ground-properly-when-flying-in-manual-flight-mode/ topic. The logs can be seen here https://www.mediafire.com/folder/jbuu2or25tjdr/position-flight-mode-logs

                            Thanks!

                            Eric KatzfeyE Offline
                            Eric KatzfeyE Offline
                            Eric Katzfey
                            ModalAI Team
                            wrote on last edited by
                            #13

                            @vjuliani Yes, 0 is automatic.

                            V 1 Reply Last reply
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                            • Eric KatzfeyE Eric Katzfey

                              @vjuliani Yes, 0 is automatic.

                              V Offline
                              V Offline
                              vjuliani
                              Contributor
                              wrote on last edited by vjuliani
                              #14

                              @Eric-Katzfey

                              Ok, thanks

                              Can I use the file:
                              https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-px4-params/-/blob/master/params/v1.14/ci_helpers/ci_sentinel.params

                              To configure RB5 px4 parameters using QGC?

                              I didn't find a specific file to RB5 in the folder

                              tomT 1 Reply Last reply
                              0
                              • V vjuliani

                                @Eric-Katzfey

                                Ok, thanks

                                Can I use the file:
                                https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-px4-params/-/blob/master/params/v1.14/ci_helpers/ci_sentinel.params

                                To configure RB5 px4 parameters using QGC?

                                I didn't find a specific file to RB5 in the folder

                                tomT Offline
                                tomT Offline
                                tom
                                admin
                                wrote on last edited by tom
                                #15

                                @vjuliani You'll want to use these: https://gitlab.com/voxl-public/voxl-sdk/utilities/voxl-px4-params/-/blob/master/params/v1.14/platforms/Sentinel_V1.params

                                Or you can run

                                voxl-configure-px4-params --platform MRB-D0006
                                
                                1 Reply Last reply
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                                • V Offline
                                  V Offline
                                  vjuliani
                                  Contributor
                                  wrote on last edited by vjuliani
                                  #16

                                  @Eric-Katzfey @tom

                                  After running "voxl-configure-px4-params --platform MRB-D0006" to configure RB5 PX4 parameters, I could perform an outdoors flight with RB5 using Position Flight Mode without GPS or motor problems: https://youtu.be/D8zP0hOx8wc

                                  It seems that the issue was RB5 running with Sentinel PX4 parameters after SDK upgrade.

                                  Thank you very much guys for your help

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