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Web Camera Node

  • This node can publish ROS image messages to port 8080 of a webpage, providing the functionality to view camera images via a web browser.

Viewing Images Via Webpage​

  • Viewing Methods

    • Local Viewing

      • Open a web browser and enter the URL: localhost:8080

    • Local Network Viewing

      • Open a web browser and enter the URL: Robot's IP:8080

        • For example: 192.168.31.198:8080

  • Viewing Images

    • Head Camera

      • Click on /camera/color/'s image_raw

    • Chin Camera

      • Click on /chin_camera/'s image

Node Startup​

  • Node Name

    • web_video_server

  • Package Path

    • ~/robot_ros_application/catkin_ws/src/web_video_server

  • Starting the Node

    • Method 1

      • The robot will automatically run the ~/start.sh script upon startup, which starts a series of basic functional nodes, including web_video_server. Therefore, this node is already running after the robot is powered on.

      • You can view all active nodes using the Ubuntu command rosnode list, where web_video_server corresponds to /web_video_server.

        lemon@lemon-NUC8i3BEH:~$ rosnode list 
        /BodyHubNode
        /SensorHubNode
        /camera/realsense2_camera
        /camera/realsense2_camera_manager
        /chin_camera
        /head_toward_sound
        /ik_module_node
        /joystick_handle_node
        /keyboards_node
        /mqtt_node
        /ros_aiui_node
        /ros_broadcast_node
        /ros_color_node
        /ros_face_node
        /ros_fruit_node
        /ros_gesture_node
        /ros_label_node
        /ros_mic_arrays
        /ros_msg_node
        /ros_socket_node
        /ros_speech_node
        /rosout
        /slam_mapping_node
        /vision_node
        /web_video_server                   # web_video_server node

      • If you receive a prompt that the page cannot be accessed when opening the webpage, it may indicate that the node has not started or has exited abnormally. The solution is as follows:

        • If you enter rosnode list in the terminal and receive the prompt ERROR: Unable to communicate with master!, like this:

          lemon@lemon-NUC8i3BEH:~$ rosnode list 
          ERROR: Unable to communicate with master!

          • Simply rerun the start.sh script:

            cd ~/ && ./start.sh

        • If the active node list output is missing only the web_video_server node compared to the table above, you can use Method 2 to run this node individually.

    • Method 2

      • Run the node individually

        source ~/robot_ros_application/catkin_ws/devel/setup.bash
        rosrun web_video_server web_video_server

        After starting the node, do not close this terminal or manually interrupt the node, as the webpage display of the camera image relies on the normal operation of this node.