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  3. FC v2 Collision prevention issue with voxl 2

FC v2 Collision prevention issue with voxl 2

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  • S Sean Hickey

    @Jetson-Nano

    Can you see if you are using the MO169 or the MO178?

    Jetson NanoJ Offline
    Jetson NanoJ Offline
    Jetson Nano
    Veteran
    wrote last edited by
    #10

    @Sean-Hickey I am using M0178

    S 1 Reply Last reply
    0
    • Jetson NanoJ Jetson Nano

      @Sean-Hickey I am using M0178

      S Offline
      S Offline
      Sean Hickey
      wrote last edited by Sean Hickey
      #11

      @Jetson-Nano

      I was able to identify the issue.

      mpc_pos_mode - acceleration based doesn't call Collision Prevention in any of the newest PX4 builds..

      You need to use mpc_pos_mode - Simple Position Control (0) or mpc_pos_mode - smooth position control (3).

      I was able to test this on a similar setup, and confirmed that collision prevention only worked with the mpc_pos_mode indicated above, and notably did not with mpc_pos_mode acceleration.

      Jetson NanoJ 1 Reply Last reply
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      • S Sean Hickey

        @Jetson-Nano

        I was able to identify the issue.

        mpc_pos_mode - acceleration based doesn't call Collision Prevention in any of the newest PX4 builds..

        You need to use mpc_pos_mode - Simple Position Control (0) or mpc_pos_mode - smooth position control (3).

        I was able to test this on a similar setup, and confirmed that collision prevention only worked with the mpc_pos_mode indicated above, and notably did not with mpc_pos_mode acceleration.

        Jetson NanoJ Offline
        Jetson NanoJ Offline
        Jetson Nano
        Veteran
        wrote last edited by
        #12

        @Sean-Hickey that great, just making sure, did you use optical flow with FC?

        Also could you let me know which branch you used, or the Px4 built file. i want to test it out in my setup.

        S 1 Reply Last reply
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        • Jetson NanoJ Jetson Nano

          @Sean-Hickey that great, just making sure, did you use optical flow with FC?

          Also could you let me know which branch you used, or the Px4 built file. i want to test it out in my setup.

          S Offline
          S Offline
          Sean Hickey
          wrote last edited by
          #13

          @Jetson-Nano

          I used VIO with FC, but the path from obstacle detection to Collision Prevention is unchanged between the 2 modes.

          I used the mainline ModalAI PX4 SDK branch. I can share the built px4 deb build with you if that's helpful, but I would try changing the mpc_pos_mode parameter first on your current build to see if that fixes your issue.

          Jetson NanoJ 1 Reply Last reply
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          • S Sean Hickey

            @Jetson-Nano

            I used VIO with FC, but the path from obstacle detection to Collision Prevention is unchanged between the 2 modes.

            I used the mainline ModalAI PX4 SDK branch. I can share the built px4 deb build with you if that's helpful, but I would try changing the mpc_pos_mode parameter first on your current build to see if that fixes your issue.

            Jetson NanoJ Offline
            Jetson NanoJ Offline
            Jetson Nano
            Veteran
            wrote last edited by
            #14

            @Sean-Hickey
            I already checked with changing the MPC_POS_MODE, did not work.

            Could you share the file, I would like to test it out.

            S 2 Replies Last reply
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            • Jetson NanoJ Jetson Nano

              @Sean-Hickey
              I already checked with changing the MPC_POS_MODE, did not work.

              Could you share the file, I would like to test it out.

              S Offline
              S Offline
              Sean Hickey
              wrote last edited by
              #15

              @Jetson-Nano

              voxl-px4_1.14.0-2.0.142_arm64.deb

              favicon

              Google Docs (drive.google.com)

              I attached the link above, I am using parameters:

              MPC_POS_MODE: Simple position control
              CP_DIST 1.5 m
              CP_DELAY 0.4 s
              CP_GUIDE_ANG : 0 deg
              CP_GO_NO_DATA: Enabled

              1 Reply Last reply
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              • Jetson NanoJ Jetson Nano

                @Sean-Hickey
                I already checked with changing the MPC_POS_MODE, did not work.

                Could you share the file, I would like to test it out.

                S Offline
                S Offline
                Sean Hickey
                wrote last edited by Sean Hickey
                #16

                @Jetson-Nano

                If this doesn't work, on the mavlink console (after testing the collision prevention) call:
                listener obstacle_distance_fused 1
                listener collision_constraints 1

                and let me know the results.

                Jetson NanoJ 2 Replies Last reply
                0
                • S Sean Hickey

                  @Jetson-Nano

                  If this doesn't work, on the mavlink console (after testing the collision prevention) call:
                  listener obstacle_distance_fused 1
                  listener collision_constraints 1

                  and let me know the results.

                  Jetson NanoJ Offline
                  Jetson NanoJ Offline
                  Jetson Nano
                  Veteran
                  wrote last edited by Jetson Nano
                  #17

                  @Sean-Hickey
                  sorry to disturb you again .
                  I am not able to flash with the deb file, could you please share the .px4 file

                  1 Reply Last reply
                  0
                  • S Sean Hickey

                    @Jetson-Nano

                    If this doesn't work, on the mavlink console (after testing the collision prevention) call:
                    listener obstacle_distance_fused 1
                    listener collision_constraints 1

                    and let me know the results.

                    Jetson NanoJ Offline
                    Jetson NanoJ Offline
                    Jetson Nano
                    Veteran
                    wrote last edited by
                    #18

                    @Sean-Hickey

                    I tested with this firmware modalai_fc-v2_1.14.0-2.0.133.px4 from (http://voxl-packages.modalai.com/dists/fc-v2/sdk-1.6/ ) and it worked, but there is no uavcan thats the only problem.

                    I checked with the parameters you mentioned.

                    When i reduce the cp_dist it stops working but with 1.5 m it is working.

                    Eric KatzfeyE 1 Reply Last reply
                    1
                    • Jetson NanoJ Jetson Nano

                      @Sean-Hickey

                      I tested with this firmware modalai_fc-v2_1.14.0-2.0.133.px4 from (http://voxl-packages.modalai.com/dists/fc-v2/sdk-1.6/ ) and it worked, but there is no uavcan thats the only problem.

                      I checked with the parameters you mentioned.

                      When i reduce the cp_dist it stops working but with 1.5 m it is working.

                      Eric KatzfeyE Offline
                      Eric KatzfeyE Offline
                      Eric Katzfey
                      ModalAI Team
                      wrote last edited by
                      #19

                      @Jetson-Nano Can you rebuild to add UAVCAN? The code is here: https://github.com/modalai/px4-firmware/tree/v1.14.0-2.0.133-dev

                      1 Reply Last reply
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