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98% Packet Loss between QGC & Vehicle

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  • Chuck BokathC Offline
    Chuck BokathC Offline
    Chuck Bokath
    Contributor
    wrote on last edited by
    #3

    I dont think so. QGC is connected on the VPN. I only have VPN comm link definitions. Are there any parms that can be adjusted for message rates on the vehicle?

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    • tomT Offline
      tomT Offline
      tom
      admin
      wrote on last edited by
      #4

      @Chuck-Bokath Are you using a Windows machine to run QGroundControl? If so, there are known issues with the default firewall settings that need to be tweaked.

      From https://docs.qgroundcontrol.com/master/en/Support/troubleshooting_qgc.html feb5f33a-232c-452e-9ae2-9515672b583e-image.png

      Chuck BokathC 1 Reply Last reply
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      • tomT tom

        @Chuck-Bokath Are you using a Windows machine to run QGroundControl? If so, there are known issues with the default firewall settings that need to be tweaked.

        From https://docs.qgroundcontrol.com/master/en/Support/troubleshooting_qgc.html feb5f33a-232c-452e-9ae2-9515672b583e-image.png

        Chuck BokathC Offline
        Chuck BokathC Offline
        Chuck Bokath
        Contributor
        wrote on last edited by
        #5

        @tom The vehicle connects. I am just dropping a ton of packets. I followed the instructions, Ground Control is allowed.

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        • tomT Offline
          tomT Offline
          tom
          admin
          wrote on last edited by
          #6

          @Chuck-Bokath I'll mirror your setup and do some digging.

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          • tomT Offline
            tomT Offline
            tom
            admin
            wrote on last edited by
            #7

            @Chuck-Bokath Okay so what I have setup is a VOXL Flight connected to our OpenVPN server using a V2 LTE modem and a Google Fi SIM. I then have QGC running on my Ubuntu desktop machine which is also connected to my VPN server. I have voxl-vision-px4 running on my VOXL Flight pointing to the IP address of my ground station assigned by the VPN server.

            Here is my current packet loss % e0251dc2-b0d3-456d-926e-a0268cb4cde3-image.png
            Completely normal sitting around 5% and dropping.

            A couple thoughts for you:

            1. A constant connection / disconnection could be related to two different devices attempting to use the same key to connect to your VPN server and they are constantly kicking each other off. So that is one thing to check. Make sure the VOXL and ground control station are using unique keys.

            2. We have seen in the past where Windows machines have bandwidth issue when using QGC. Do you have a machine with Ubuntu 18.04 on it that you could test with? This is the OS that the majority of our internal machines are loaded with.

            Chuck BokathC 1 Reply Last reply
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            • tomT tom

              @Chuck-Bokath Okay so what I have setup is a VOXL Flight connected to our OpenVPN server using a V2 LTE modem and a Google Fi SIM. I then have QGC running on my Ubuntu desktop machine which is also connected to my VPN server. I have voxl-vision-px4 running on my VOXL Flight pointing to the IP address of my ground station assigned by the VPN server.

              Here is my current packet loss % e0251dc2-b0d3-456d-926e-a0268cb4cde3-image.png
              Completely normal sitting around 5% and dropping.

              A couple thoughts for you:

              1. A constant connection / disconnection could be related to two different devices attempting to use the same key to connect to your VPN server and they are constantly kicking each other off. So that is one thing to check. Make sure the VOXL and ground control station are using unique keys.

              2. We have seen in the past where Windows machines have bandwidth issue when using QGC. Do you have a machine with Ubuntu 18.04 on it that you could test with? This is the OS that the majority of our internal machines are loaded with.

              Chuck BokathC Offline
              Chuck BokathC Offline
              Chuck Bokath
              Contributor
              wrote on last edited by
              #8

              @tom Thanks for the tips. I'll verify the key issue with openvpn. That didnt occur to me. They are both using the same key. I do have several machines with Ubuntu on them. I'll try that next. Thanks!

              w/r/t voxl-vision-px4 running and attempting to run a shell script after openvpn connects much less pinging a server on the vpn; -- should the voxl system experience such a large load making those operations fail?

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              • tomT Offline
                tomT Offline
                tom
                admin
                wrote on last edited by
                #9

                @Chuck-Bokath Those shouldn't be super large loads so that shouldn't interfere with any of the other processes on VOXL. I'm guessing it's all related to the keys, that would explain a lot of this behavior that you're seeing.

                Chuck BokathC 1 Reply Last reply
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                • tomT tom

                  @Chuck-Bokath Those shouldn't be super large loads so that shouldn't interfere with any of the other processes on VOXL. I'm guessing it's all related to the keys, that would explain a lot of this behavior that you're seeing.

                  Chuck BokathC Offline
                  Chuck BokathC Offline
                  Chuck Bokath
                  Contributor
                  wrote on last edited by
                  #10

                  @tom It may have done the trick. I had QGC running in the background with the vehicle on, connected to the vpn. When I changed the keys; the vehicle's led 1 changed from solid green to flashing green, then to flashing red. I googled around for the led flash pattern, bc it never seems good when a system flashes red - I haven't found what flash red mean yet, though i ran across a mention where flashing green means firmware upgrade? I suspect the red means the flash of the firmware failed. I can't get back into the system via adb or any method so far. If, in fact the flashing red light mean error with the firmware can you point me to the correct docs to reload the firmware and get my system back to the previous state? I feel that the key issue was the culprit.

                  thank you!

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                  • tomT Offline
                    tomT Offline
                    tom
                    admin
                    wrote on last edited by
                    #11

                    @Chuck-Bokath Can you describe the hardware you're using? Is it just an M500 or a custom build? Can you also describe which LED is doing this behavior, or send a picture or video of what you're seeing so we can figure out what is going on?

                    No ADB can mean a couple things. See this topic for some instructions on how to get it back: https://forum.modalai.com/topic/488/adb-or-wi-fi-no-longer-communicating?_=1636651334161

                    Chuck BokathC 1 Reply Last reply
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                    • tomT tom

                      @Chuck-Bokath Can you describe the hardware you're using? Is it just an M500 or a custom build? Can you also describe which LED is doing this behavior, or send a picture or video of what you're seeing so we can figure out what is going on?

                      No ADB can mean a couple things. See this topic for some instructions on how to get it back: https://forum.modalai.com/topic/488/adb-or-wi-fi-no-longer-communicating?_=1636651334161

                      Chuck BokathC Offline
                      Chuck BokathC Offline
                      Chuck Bokath
                      Contributor
                      wrote on last edited by
                      #12

                      @tom Tom, Thanks for the help. The connection issue was definitively the VPN key. I used the same keys with different login credentials. I created a new user cert, and new profile, associated those 2 together downloaded the ovpn and create a separate instance of the vpn session. No problem connecting with the vehicle, though it says thats its at 60% loss. I have a goo connection with ATT at -90 RSRP, low SNR.

                      The flickering lights appear to be from a bad battery. I change batteries when I went into the office, and all was better.

                      Also, the ability to push the signals from the modem to a server via wget works well. I believe that was symptom of the vpn key issue.

                      Now, I just need to figure out how to compile a c program to use the voxl-inspect-gps program to pull real time off the gps pipe. Is there a concise document you can point me to? Will I need to compile on a ubuntu system then push it over to the vehicle? Thats fine, I am use to that..

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                      • tomT Offline
                        tomT Offline
                        tom
                        admin
                        wrote on last edited by
                        #13

                        @Chuck-Bokath Great to hear that you're making progress. As for developing your new program you can use the voxl-emulator docker image: https://docs.modalai.com/voxl-emulator/ in order to compile programs for VOXL on an Ubuntu machine. Here is a good doc on MPA https://docs.modalai.com/voxl-sdk/#what-is-modal-pipe-architecture-mpa

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