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Implementing PX4 avoidance in mission mode using the voxl and QGC

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  • S Offline
    S Offline
    scottesicdrone
    Contributor
    wrote on last edited by
    #11

    Thank you for your help, the UDP connection seems to be working for the most part! The connection is initiated and the ROS connections seem to be connected but it seems like the pointcloud isn't being updated fast enough. I checked the pointcloud topic made by the snap_dfs manager and that was being updated at around 2Hz at most and the avoidance algorithm requires the pointcloud to updated at least 10Hz. I also opened up the pointcloud in rviz and saw that the pointcloud was updating at that rate. Is this normal behavior or is something else going on here? I apologize that I keep encountering roadblocks but I do think I am close to getting this!

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    • Chad SweetC Offline
      Chad SweetC Offline
      Chad Sweet
      ModalAI Team
      wrote on last edited by
      #12

      Check out the bottom of this readme where it recommends different parameters to increase frame rate. https://github.com/ATLFlight/dfs-ros-example

      Basically, in any computer vision task it's a tradeoff of frame rate and resolution

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      • Chad SweetC Offline
        Chad SweetC Offline
        Chad Sweet
        ModalAI Team
        wrote on last edited by
        #13

        And FWIW, you don't need high resolution for obstacle avoidance. Just need to see things not to run in to!

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        • Chad SweetC Offline
          Chad SweetC Offline
          Chad Sweet
          ModalAI Team
          wrote on last edited by
          #14

          @scottesicdrone curious to see if you were you able to get things working?

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          • J DataJ Offline
            J DataJ Offline
            J Data
            wrote on last edited by J Data
            #15

            @Chad-Sweet
            I had a look the link you shared: snap_vio
            But I think it is not working correctly with the voxl module I have.
            Currently, I am running ROS noetic on the voxl module, and try to run the VIO with downward camer.
            By using snap_camera_ros (I edited it a little bit to use the downward camera), I can see the downward camera is correctly set up for snap_vio. Also, I can see snap_imu is working correctly, so I can see the output of imu (angular_velocity and linear_acceleration).

            But I cannot see any output of /downward/vio/odometry.

            Could you please help me to run snap_vio with the voxl module?
            What should I check first?

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            • J DataJ Offline
              J DataJ Offline
              J Data
              wrote on last edited by
              #16

              The running file is similar with this.

              <!-- camera nodelet -->
              <!-- VIO nodelet -->
              <!-- fisheye camera info spoofer -->
              <!-- imu nodelet -->
              <!-- cpa nodelet -->
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              • J DataJ Offline
                J DataJ Offline
                J Data
                wrote on last edited by J Data
                #17

                @Chad-Sweet
                Update.

                I have output /downward/vio/odometry with some error messages

                [ INFO] [1648150781.892213161]: [VISLAM] Got uav1/imu to uav1/dfc transform; Initializing VISLAM
                [ INFO] [1648150781.892816862]: [VISLAM] (from tf) tbc:
                x: 0.2
                y: 0
                z: -0.025
                
                [ INFO] [1648150781.893485304]: [VISLAM] (from tf) ombc:
                X: 0
                Y: 2.356
                Z: 0
                
                MachineVision is licensed as community user
                LNX_8074 supported? 1
                LNX_8096 supported? 1
                LNX_IA64 supported? 1
                WINDOWS supported? 0
                AR ERROR: arFileOpen(): Failed to open file: /data/.ros/vislam/Configuration.SF.xml
                FASTCV: fcvAvailableHardware Linux
                mempool cur block size 307200, new block size 307200
                AR ERROR: arFileOpen(): Failed to open file: /data/.ros/na
                
                Error:   TF_NAN_INPUT: Ignoring transform for child_frame_id "grav" from authority "unknown_publisher" because of a nan value in the transform (0.000000 0.000000 0.000000) (-nan -nan -nan nan)
                         at line 244 in ~/geometry2/tf2/src/buffer_core.cpp
                Error:   TF_DENORMALIZED_QUATERNION: Ignoring transform for child_frame_id "grav" from authority "unknown_publisher" because of an invalid quaternion in the transform (-nan -nan -nan nan)
                         at line 257 in ~/geometry2/tf2/src/buffer_core.cpp
                [ERROR] [1648150782.073463584]: Ignoring transform for child_frame_id "grav" from authority "unknown_publisher" because of a nan value in the transform (0.000000 0.000000 0.000000) (-nan -nan -nan nan)
                [ERROR] [1648150782.077556213]: Ignoring transform for child_frame_id "grav" from authority "unknown_publisher" because of an invalid quaternion in the transform (-nan -nan -nan nan)
                [ERROR] [1648150782.094956631]: Ignoring transform for child_frame_id "grav" from authority "unknown_publisher" because of a nan value in the transform (0.000000 0.000000 0.000000) (-nan -nan -nan nan)
                [ERROR] [1648150782.095484499]: Ignoring transform for child_frame_id "grav" from authority "unknown_publisher" because of an invalid quaternion in the transform (-nan -nan -nan nan)
                Error:   TF_NAN_INPUT: Ignoring transform for child_frame_id "grav" from authority "unknown_publisher" because of a nan value in the transform (0.000000 0.000000 0.000000) (-nan -nan -nan nan)
                         at line 244 in ~/tf2/src/buffer_core.cpp
                Error:   TF_DENORMALIZED_QUATERNION: Ignoring transform for child_frame_id "grav" from authority "unknown_publisher" because of an invalid quaternion in the transform (-nan -nan -nan nan)
                         at line 257 in ~/geometry2/tf2/src/buffer_core.cpp
                

                and repeated error message of

                [ERROR] [1648150919.088496536]: [VISLAM] ERROR CODE = 2048, Stamp: 1648150919.022946523
                

                I am wondering how urdf should be set. Should there be any rotations of IMU or camera in urdf file?
                urdf file I used has some rotations in y-axis for IMU and cameras.

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                • J DataJ Offline
                  J DataJ Offline
                  J Data
                  wrote on last edited by
                  #18

                  @Chad-Sweet
                  I am using customized urdf for snap_vio which has different numbers (positions and orientations) of sdf_pro.urdf.

                  Is there any urdf file for VOXL?

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                  • J DataJ Offline
                    J DataJ Offline
                    J Data
                    wrote on last edited by
                    #19

                    @Chad-Sweet , No matter the tf setting in the urdf file is, the ros topic outputs are shown in the followings

                    1. rostopic echo mavros/imu/data (in base_link frame): x is backward, y is right, z is down
                    2. rostopic echo downward/imu (in imu frame): x is right, y is backward, z is down
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                    • J DataJ Offline
                      J DataJ Offline
                      J Data
                      wrote on last edited by
                      #20

                      @modalab Hello, can you help me to resolve this problem?

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