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Unable to subscribe to vehicle_command_position topic

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  • Darshit DesaiD Offline
    Darshit DesaiD Offline
    Darshit Desai
    Regular
    wrote on last edited by Darshit Desai
    #1

    Hi @Moderator I have been trying to subscribe to vehicle_local_position ROS2 PX4 topic in my code but that wasn't working so I checked by echoing the topic directly from the terminal and it shows this error?

    c39768a1-c454-4f6f-a893-6aca2dc148c2-image.png

    After doing some search online, I found that the PX4 and px4_msgs version might be different, since I am using voxl_ros2_foxy any ideas why this would be happening?

    Voxl version info

    voxl2:~/ros2_ws/src/Project_LegionAir(ROS2-port)$ voxl-version
    --------------------------------------------------------------------------------
    system-image: 1.7.1-M0054-14.1a-perf-nightly-20231025
    kernel:       #1 SMP PREEMPT Thu Oct 26 03:25:38 UTC 2023 4.19.125
    --------------------------------------------------------------------------------
    hw version:   M0054
    --------------------------------------------------------------------------------
    voxl-suite:   1.1.2
    --------------------------------------------------------------------------------
    Packages:
    Repo:  http://voxl-packages.modalai.com/ ./dists/qrb5165/sdk-1.1/binary-arm64/
    Last Updated: 2024-05-07 06:01:21
    List:
    	libmodal-cv                 0.4.0
    	libmodal-exposure           0.1.0
    	libmodal-journal            0.2.2
    	libmodal-json               0.4.3
    	libmodal-pipe               2.9.2
    	libqrb5165-io               0.4.2
    	libvoxl-cci-direct          0.2.1
    	libvoxl-cutils              0.1.1
    	mv-voxl                     0.1-r0
    	qrb5165-bind                0.1-r0
    	qrb5165-dfs-server          0.2.0
    	qrb5165-imu-server          1.0.1
    	qrb5165-rangefinder-server  0.1.1
    	qrb5165-slpi-test-sig       01-r0
    	qrb5165-system-tweaks       0.2.3
    	qrb5165-tflite              2.8.0-2
    	voxl-bind-spektrum          0.1.0
    	voxl-camera-calibration     0.5.3
    	voxl-camera-server          1.8.9.1
    	voxl-configurator           0.4.8
    	voxl-cpu-monitor            0.4.7
    	voxl-docker-support         1.3.0
    	voxl-elrs                   0.1.3
    	voxl-esc                    1.3.7
    	voxl-feature-tracker        0.3.2
    	voxl-flow-server            0.3.3
    	voxl-gphoto2-server         0.0.10
    	voxl-jpeg-turbo             2.1.3-5
    	voxl-lepton-server          1.2.0
    	voxl-libgphoto2             0.0.4
    	voxl-libuvc                 1.0.7
    	voxl-logger                 0.3.5
    	voxl-mavcam-manager         0.5.3
    	voxl-mavlink                0.1.1
    	voxl-mavlink-server         1.3.2
    	voxl-microdds-agent         2.4.1-0
    	voxl-modem                  1.0.8
    	voxl-mongoose               7.7.0-1
    	voxl-mpa-to-ros             0.3.7
    	voxl-mpa-to-ros2            0.0.2
    	voxl-mpa-tools              1.1.3
    	voxl-neopixel-manager       0.0.3
    	voxl-opencv                 4.5.5-2
    	voxl-portal                 0.6.3
    	voxl-px4                    1.14.0-2.0.63
    	voxl-px4-imu-server         0.1.2
    	voxl-px4-params             0.3.3
    	voxl-qvio-server            1.0.0
    	voxl-remote-id              0.0.9
    	voxl-ros2-foxy              0.0.1
    	voxl-streamer               0.7.4
    	voxl-suite                  1.1.2
    	voxl-tag-detector           0.0.4
    	voxl-tflite-server          0.3.2
    	voxl-utils                  1.3.3
    	voxl-uvc-server             0.1.6
    	voxl-vision-hub             1.7.3
    	voxl2-system-image          1.7.1-r0
    	voxl2-wlan                  1.0-r0
    --------------------------------------------------------------------------------
    
    1 Reply Last reply
    0
    • B Offline
      B Offline
      brahim
      Contributor
      wrote on last edited by
      #2

      What px4_msgs branch or tag are you using? Please post the branch name. The px4_msgs repo branch is in lockstep with the PX4 branch release, so if there is a mismatch I would expect deserialization issues.

      B 1 Reply Last reply
      0
      • B brahim

        What px4_msgs branch or tag are you using? Please post the branch name. The px4_msgs repo branch is in lockstep with the PX4 branch release, so if there is a mismatch I would expect deserialization issues.

        B Offline
        B Offline
        brahim
        Contributor
        wrote on last edited by brahim
        #3

        @Darshit-Desai Here is the output from echo'ing local position.

        voxl2:~/colcon_ws$ ros2 topic list
        /fmu/in/obstacle_distance
        /fmu/in/offboard_control_mode
        /fmu/in/onboard_computer_status
        /fmu/in/sensor_optical_flow
        /fmu/in/telemetry_status
        /fmu/in/trajectory_setpoint
        /fmu/in/vehicle_attitude_setpoint
        /fmu/in/vehicle_command
        /fmu/in/vehicle_mocap_odometry
        /fmu/in/vehicle_rates_setpoint
        /fmu/in/vehicle_trajectory_bezier
        /fmu/in/vehicle_trajectory_waypoint
        /fmu/in/vehicle_visual_odometry
        /fmu/out/failsafe_flags
        /fmu/out/position_setpoint_triplet
        /fmu/out/sensor_combined
        /fmu/out/timesync_status
        /fmu/out/vehicle_attitude
        /fmu/out/vehicle_control_mode
        /fmu/out/vehicle_local_position
        /fmu/out/vehicle_odometry
        /fmu/out/vehicle_status
        /parameter_events
        /rosout
        voxl2:~/colcon_ws$ ros2 topic echo /fmu/out/vehicle_local_position
        timestamp: 1716299017260605
        timestamp_sample: 1716299017259933
        xy_valid: false
        z_valid: true
        v_xy_valid: false
        v_z_valid: true
        x: -0.015882886946201324
        y: -0.006520443130284548
        z: 3.26619815826416
        delta_xy: [-9.292006097894046e-08, -1.9959152552928572e-07]
        xy_reset_counter: 1
        delta_z: 0.0
        z_reset_counter: 1
        vx: 0.0007984319818206131
        vy: -0.001192234456539154
        vz: 0.006735446862876415
        z_deriv: 0.014136962592601776
        delta_vxy: [-1.0643154382705688e-05, -2.2861408069729805e-05]
        vxy_reset_counter: 1
        delta_vz: 1.583993434906006e-05
        vz_reset_counter: 1
        ax: 0.042993903160095215
        ay: -0.06323475390672684
        az: -0.10127022862434387
        heading: -0.12067540735006332
        delta_heading: 0.0
        heading_reset_counter: 0
        heading_good_for_control: false
        xy_global: false
        z_global: false
        ref_timestamp: 0
        ref_lat: .nan
        ref_lon: .nan
        ref_alt: .nan
        dist_bottom: 0.10000000149011612
        dist_bottom_valid: false
        dist_bottom_sensor_bitfield: 0
        eph: 0.012850395403802395
        epv: 0.3351651430130005
        evh: 0.04047877714037895
        evv: 0.06853056699037552
        dead_reckoning: true
        vxy_max: .inf
        vz_max: .inf
        hagl_min: .inf
        hagl_max: .inf
        ---
        
        

        Voxl version

        system-image: 1.7.4-M0054-14.1a-perf
        kernel:       #1 SMP PREEMPT Fri Feb 9 21:59:24 UTC 2024 4.19.125
        --------------------------------------------------------------------------------
        hw platform:  M0054
        mach.var:     1.0
        --------------------------------------------------------------------------------
        voxl-suite:   1.1.3-1
        Packages:
        Repo:  http://voxl-packages.modalai.com/ ./dists/qrb5165/sdk-1.1/binary-arm64/
        Last Updated: 2024-05-21 13:30:13
        List:
        kernel-module-voxl-fsync-mod-4.19.125     1.0-r0
        kernel-module-voxl-gpio-mod-4.19.125      1.0-r0
        kernel-module-voxl-platform-mod-4.19.125  1.0-r0
        libmodal-cv                               0.4.0
        libmodal-exposure                         0.1.0
        libmodal-journal                          0.2.2
        libmodal-json                             0.4.3
        libmodal-pipe                             2.9.2
        libqrb5165-io                             0.4.2
        libvoxl-cci-direct                        0.2.1
        libvoxl-cutils                            0.1.1
        mv-voxl                                   0.1-r0
        qrb5165-bind                              0.1-r0
        qrb5165-dfs-server                        0.2.0
        qrb5165-imu-server                        1.0.1
        qrb5165-rangefinder-server                0.1.1
        qrb5165-slpi-test-sig                     01-r0
        qrb5165-system-tweaks                     0.2.6
        qrb5165-tflite                            2.8.0-2
        voxl-bind-spektrum                        0.1.0
        voxl-camera-calibration                   0.5.3
        voxl-camera-server                        1.8.9
        voxl-ceres-solver                         2:1.14.0-10
        voxl-configurator                         0.5.2
        voxl-cpu-monitor                          0.4.7
        voxl-docker-support                       1.3.0
        voxl-elrs                                 0.1.3
        voxl-esc                                  1.4.0
        voxl-feature-tracker                      0.3.2
        voxl-flow-server                          0.3.3
        voxl-fsync-mod                            1.0-r0
        voxl-gphoto2-server                       0.0.10
        voxl-gpio-mod                             1.0-r0
        voxl-jpeg-turbo                           2.1.3-5
        voxl-lepton-server                        1.2.0
        voxl-libgphoto2                           0.0.4
        voxl-libuvc                               1.0.7
        voxl-logger                               0.3.5
        voxl-mavcam-manager                       0.5.3
        voxl-mavlink                              0.1.1
        voxl-mavlink-server                       1.3.2
        voxl-microdds-agent                       2.4.1-0
        voxl-modem                                1.0.8
        voxl-mongoose                             7.7.0-1
        voxl-mpa-to-ros                           0.3.7
        voxl-mpa-to-ros2                          0.0.2
        voxl-mpa-tools                            1.1.3
        voxl-neopixel-manager                     0.0.3
        voxl-open-vins                            0.4.4
        voxl-open-vins-server                     0.2.18
        voxl-opencv                               4.5.5-2
        voxl-platform-mod                         1.0-r0
        voxl-portal                               0.6.3
        voxl-px4                                  1.14.0-2.0.63
        voxl-px4-imu-server                       0.1.2
        voxl-px4-params                           0.3.3
        voxl-qvio-server                          1.0.0
        voxl-remote-id                            0.0.9
        voxl-ros2-foxy                            0.0.1
        voxl-streamer                             0.7.4
        voxl-suite                                1.1.3-1
        voxl-tag-detector                         0.0.4
        voxl-tflite-server                        0.3.1
        voxl-utils                                1.3.8
        voxl-uvc-server                           0.1.6
        voxl-vision-hub                           1.7.3
        voxl2-system-image                        1.7.4-r0
        voxl2-wlan                                1.0-r0
        --------------------------------------------------------------------------------
        
        

        px4_msgs branch

        voxl2:~/colcon_ws/src/px4_msgs(release/1.14)$ git branch
        * release/1.14
        
        
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