# CameraManager::Initialize() failed on tracking_slave.launch

Source: https://forum.modalai.com/topic/203/cameramanager-initialize-failed-on-tracking_slave-launch
Category: General Questions (https://forum.modalai.com/category/2/general-questions)
Posted: 2021-04-18 09:19:45 UTC by shlee853
Replies: 1 · Views: 388

## shlee853 · 2021-04-18 09:19:45 UTC

Hi guys,

I'm testing on apriltag using flight deck.
I configured my voxl-vision-px4.conf as like this.

/**
 * VOXL Vision PX4 Configuration File
 *
 */
{
        "qgc_ip":       "192.168.219.182",
        "en_localhost_mavlink_udp":     true,
        "en_secondary_qgc":     false,
        "secondary_qgc_ip":     "192.168.1.214",
        "qgc_udp_port_number":  14550,
        "localhost_udp_port_number":    14551,
        "en_vio":       true,
        "en_voa":       false,
        "en_send_vio_to_qgc":   false,
        "en_send_voa_to_qgc":   false,
        "en_adsb":      false,
        "adsb_uart_bus":        7,
        "adsb_uart_baudrate":   57600,
        "px4_uart_bus": 5,
        "px4_uart_baudrate":    921600,
        "offboard_mode":        "figure_eight",

    "R_imu_to_body":    [[0, 1, 0], [1, 0, 0], [0, 0, -1]],
    "T_imu_wrt_body":   [0.068, -0.015, -0.008],
    "height_body_above_ground_m": 0.05,
    "T_stereo_wrt_body":    [0.10, -0.04, 0.0],
    "land_on_tag_id":   1,
    "follow_tag_id":    1,
    "en_apriltag_fixed_frame":  true,
    "fixed_apriltags":  [
       {
        "tag_id":   1,
        "R_tag_to_fixed":   [[0, -1, 0], [1, 0, 0], [0, 0, 1]],
        "T_tag_wrt_fixed":  [0, 0, 0]
        },
       {
        "tag_id":   0,
        "R_tag_to_fixed":   [[0, -1, 0], [1, 0, 0], [0, 0, 1]],
        "T_tag_wrt_fixed":  [0, 5, 0]
        }

     ],
    "en_transform_mavlink_pos_setpoints_from_fixed_frame":  true,
    "en_fixed_frame_pipe": false,

    "fixed_frame_filter_len": 5

}

and I launch ROS for tracking camera with salve mode.

But, camera cannot be opened.

Could you please help me it?

/ # bash
yocto:/# 
yocto:/# 
yocto:/# 
yocto:/# roslaunch voxl_cam_ros tracking_slave.launch 
... logging to /home/root/.ros/log/73ae7aaa-a026-11eb-a27f-ec5c68cd25a1/roslaunch-apq8096-3492.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://192.168.219.101:44434/

SUMMARY
========

PARAMETERS
 * /rosdistro: indigo
 * /rosversion: 1.11.21
 * /tracking/voxl_cam_nodelet/cam_id: 1
 * /tracking/voxl_cam_nodelet/cam_name: tracking
 * /tracking/voxl_cam_nodelet/frame_id: tracking_frame
 * /tracking/voxl_cam_nodelet/frame_rate: 15
 * /tracking/voxl_cam_nodelet/height: 480
 * /tracking/voxl_cam_nodelet/is_cam_master: False
 * /tracking/voxl_cam_nodelet/skip_n_frames: 0
 * /tracking/voxl_cam_nodelet/snav_raw10_compatability: True
 * /tracking/voxl_cam_nodelet/width: 640

NODES
  /tracking/
    tracking_nodelet_manager (nodelet/nodelet)
    voxl_cam_nodelet (nodelet/nodelet)

auto-starting new master
process[master]: started with pid [3511]
ROS_MASTER_URI=http://localhost:11311/

setting /run_id to 73ae7aaa-a026-11eb-a27f-ec5c68cd25a1
process[rosout-1]: started with pid [3524]
started core service [/rosout]
process[tracking/tracking_nodelet_manager-2]: started with pid [3527]
process[tracking/voxl_cam_nodelet-3]: started with pid [3534]
[ INFO] [1618737258.731583874]: Initializing nodelet with 4 worker threads.
[ INFO] [1618737258.991213919]: SnapCamDriver Starting
[ INFO] [1618737258.991545689]: Monotonic offset: 1618737188.166319025
libcam.enable.publish  1
libcam.enable.publish.dump 0
libcam.publish.buffer.policy max
libcam.publish.buffer.max 3
libcam.debug.level info
libcam.dump.dir /data/misc/camera/dumps
ERROR: could not open camera subscriber for cam id 1
[ERROR] [1618737276.166226697]: CameraManager::Initialize() failed
[ERROR] [1618737276.166769612]: Unable to open camera.

## Reply by Chad Sweet (ModalAI staff) · 2021-04-18 16:38:13 UTC

I assume you are using the master version of voxl-vision-px4.

Since the is_cam_master is false, is voxl-vision-px4 still running? vvpx4 would be the camera master in that case

Can you check what TRACKING_CAM_ID is? 

'echo $TRACKING_CAM_ID'

If you have high-res, stereo and tracking plugged in TRACKING_CAM_ID should be 1 which matches what you have in the launch file