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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

    What TOF sensor are you using for obstacle distance?

    Just confirming, you are using the ARK Flow MR facing downwards just for optical flow and position hold, but not for collision prevention?

    Jetson NanoJ Offline
    Jetson NanoJ Offline
    Jetson Nano
    Veteran
    wrote last edited by
    #8

    @Sean-Hickey PMD tof that comes with yellow board M0173 - https://docs.modalai.com/M0173/

    Yes optical flow is facing down, it is used for position hold and not for collision prevention.

    S 1 Reply Last reply
    0
    • Jetson NanoJ Jetson Nano

      @Sean-Hickey PMD tof that comes with yellow board M0173 - https://docs.modalai.com/M0173/

      Yes optical flow is facing down, it is used for position hold and not for collision prevention.

      S Offline
      S Offline
      Sean Hickey
      wrote last edited by
      #9

      @Jetson-Nano

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

      Jetson NanoJ 1 Reply Last reply
      0
      • 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
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                      • 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

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