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Collision Prevention

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  • ? Offline
    ? Offline
    A Former User
    wrote on last edited by
    #2

    System image 3.3.0 / Voxl-suite 0.4.6 supports collision prevention using stereo cameras (voxl-dfs-server) and the en_voa flag in /etc/modalai/voxl-vision-px4.conf

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    • G Offline
      G Offline
      gauravshukla914
      Regular
      wrote on last edited by
      #3

      @Alex-Gardner Thanks for the reply. I updated the image to 3.3.0. I've also set the en_voa flag to true in the configuration file. However when I do the "voxl-vision-px4 -s" to print the obstacle date, I get nothing.
      On checking the services running by voxl-inspect-services, I see that the voxl-dfs -server is enabled but not running. Is there anything else that I need to do?
      Also, I'm able to see the stereo camera output in the rqt image viewer.

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      • G Offline
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        gauravshukla914
        Regular
        wrote on last edited by
        #4

        @Alex-Gardner Also, just to let you know, we have the stereo camera replaced, so we have attempted the stereo calibration once. And we pushed the files to VOXL.
        When I do on - voxl-dfs-server I get this
        voxl-dfs-server

        skip_n_frames: 5
        n_disparity_levels: 48

        Failed to open calibration file: /data/modalai/opencv_stereo_intrinsics.yml

        But the calibaration method that we performed pushes left.yaml and right.yaml files. Is there anything wrong that I'm doing?

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        • G Offline
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          gauravshukla914
          Regular
          wrote on last edited by
          #5

          Update - we were able to push the opencv_intrinsics.yml. But when I do voxl-inspect-services, it still shows dfs server enabled, but not running.

          Prasad AntervediP 1 Reply Last reply
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          • G Offline
            G Offline
            gauravshukla914
            Regular
            wrote on last edited by
            #6

            Update - we are able to get the obstacle data printed on the terminal. But this only comes when we run the voxl-dfs-server in one terminal and then run voxl-vision-px4 -s in other terminal.
            Do we have to always run voxl-dfs-server in one window for this?

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            • ? Offline
              ? Offline
              A Former User
              wrote on last edited by
              #7

              voxl-dfs-server and voxl-vision-px4 should run in the background just fine if they're marked as enabled in voxl-inspect-services. If you boot the voxl and see that dfs server is enabled but not running, then can you paste the output of journalctl -u voxl-dfs-server so we can see why it's aborting

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              • G Offline
                G Offline
                gauravshukla914
                Regular
                wrote on last edited by
                #8

                @Alex-Gardner its now perfectly running on boot up. Thanks for the help.

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                • G Offline
                  G Offline
                  gauravshukla914
                  Regular
                  wrote on last edited by
                  #9

                  @Alex-Gardner I want to check the stereo disparity. However, when I do the voxl streamer -c dfs-server, the stream is getting stuck on the the VLC media player. How do I see the disparity output?

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                  • ? Offline
                    ? Offline
                    A Former User
                    wrote on last edited by
                    #10

                    The config option is dfs-disparity not dfs-server

                    Daniel RyuD 1 Reply Last reply
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                    • ? A Former User

                      The config option is dfs-disparity not dfs-server

                      Daniel RyuD Offline
                      Daniel RyuD Offline
                      Daniel Ryu
                      Regular
                      wrote on last edited by
                      #11

                      @Alex-Gardner Different guy, but I followed the same steps as above and am also just getting a black screen on the VLC player for

                      voxl-streamer -c dfs-disparity
                      

                      Everything else seems to be working fine when I run voxl-inspect-services (you can see my status here https://forum.modalai.com/topic/409/obstacle_detection-messages-not-appearing/3).

                      I would like to have collision avoidance integrated onto my drone for a time sensitive project, but the documentation for voxl-dfs-server is not yet present and I am out of resources to turn to.

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                      • G gauravshukla914

                        Update - we were able to push the opencv_intrinsics.yml. But when I do voxl-inspect-services, it still shows dfs server enabled, but not running.

                        Prasad AntervediP Offline
                        Prasad AntervediP Offline
                        Prasad Antervedi
                        wrote on last edited by
                        #12

                        @gauravshukla914 Hi! I am also getting the same error (i.e. "Failed to open calibration file: /data/modalai/opencv_stereo_intrinsics.yml" ). How did you manage to get the opencv_stereo_intrinsics.yml file. Did you write it yourself?
                        Thanks in advance 😄

                        Daniel RyuD 1 Reply Last reply
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                        • G Offline
                          G Offline
                          gauravshukla914
                          Regular
                          wrote on last edited by
                          #13

                          @Prasad-Antervedi as far as I rember we calibrated the stereo cameras and then pushed the resulting files into voxl.

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                          • Prasad AntervediP Prasad Antervedi

                            @gauravshukla914 Hi! I am also getting the same error (i.e. "Failed to open calibration file: /data/modalai/opencv_stereo_intrinsics.yml" ). How did you manage to get the opencv_stereo_intrinsics.yml file. Did you write it yourself?
                            Thanks in advance 😄

                            Daniel RyuD Offline
                            Daniel RyuD Offline
                            Daniel Ryu
                            Regular
                            wrote on last edited by
                            #14

                            @Prasad-Antervedi Try following these: https://docs.modalai.com/calibrate-cameras/

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