po-mobile-ros-robot

Gazebo Garden

4/20/25 TODO complete migration to Gazebo Garden

https://github.com/oc-robotics/differential_drive_robot/tree/jason

• Update lidar.xacro https://github.com/joshnewans/articubot_one/blob/new_gazebo/description/lidar.xacro

• Update camera.xacro https://github.com/joshnewans/articubot_one/blob/new_gazebo/description/camera.xacro

• Update launch file https://github.com/joshnewans/articubot_one/blob/new_gazebo/launch/launch_sim.launch.py

• Rename gz_bridge.yml to gz_bridge.yaml and update with:(https://discord.com/channels/1204942703243173918/1362926788468015285/1363385886317744283)

• Update obstacle_worlds.sdf to include sensor plugins

• Update RViz configuration to visualize camera and LiDAR data

• Get wheels moving in RViz

• Katelynn: Needs big googly eyes

Update lidar

• Update lidar.xacro

lidar.xacro

<?xml version="1.0"?>
<robot xmlns:xacro="http://www.ros.org/wiki/xacro" >
 
    <joint name="laser_joint" type="fixed">
        <parent link="chassis"/>
        <child link="laser_frame"/>
        <origin xyz="0.122 0 0.212" rpy="0 0 0"/>
    </joint>
 
    <link name="laser_frame">
        <visual>
            <geometry>
                <cylinder radius="0.05" length="0.04"/>
            </geometry>
            <material name="red"/>
        </visual>
        <visual>
            <origin xyz="0 0 -0.05"/>
            <geometry>
                <cylinder radius="0.01" length="0.1"/>
            </geometry>
            <material name="black"/>
        </visual>
        <collision>
            <geometry>
                <cylinder radius="0.05" length="0.04"/>
            </geometry>
        </collision>
        <xacro:inertial_cylinder mass="0.1" length="0.04" radius="0.05">
            <origin xyz="0 0 0" rpy="0 0 0"/>
        </xacro:inertial_cylinder>
    </link>
 
 
 
    <gazebo reference="laser_frame">
        <material>Gazebo/Black</material>
 
        <sensor name="gpu_lidar" type="gpu_lidar">
            <pose relative_to="lidar_frame"> 0 0 0 0 0 0 </pose>
            <visualize>true</visualize>
            <update_rate>10</update_rate>
            <lidar>
                <scan>
                    <horizontal>
                        <samples>360</samples>
                        <min_angle>-3.14</min_angle>
                        <max_angle>3.14</max_angle>
                    </horizontal>
                </scan>
                <range>
                    <min>0.3</min>
                    <max>12</max>
                </range>
            </lidar>
            <topic>lidar</topic>
            <gz_frame_id>laser_frame</gz_frame_id>
        </sensor>
    </gazebo>
 
</robot>

• Check scan topic

ros2 topic info /scan

Type: sensor_msgs/msg/LaserScan
Publisher count: 1
Subscription count: 0

ros2 topic echo /scan

header:
  stamp:
    sec: 3014
    nanosec: 400000000
  frame_id: laser_frame
angle_min: -3.140000104904175
angle_max: 3.140000104904175
angle_increment: 0.01749303564429283
time_increment: 0.0
scan_time: 0.0
range_min: 0.30000001192092896
range_max: 12.0
ranges:
- 0.5050193071365356
- 0.5051422715187073
- 0.5053883790969849
- 0.5057575106620789
- 0.5062493681907654
- 0.506863534450531

Add Sim Camera

• Resources

  • https://articulatedrobotics.xyz/tutorials/mobile-robot/hardware/camera
  • https://github.com/joshnewans/articubot_one/tree/new_gazebo

• Create description/camera.xacro file

description/camera.xacro

<?xml version="1.0"?>
<robot xmlns:xacro="http://www.ros.org/wiki/xacro" >
 
    <joint name="camera_joint" type="fixed">
        <parent link="chassis"/>
        <child link="camera_link"/>
        <origin xyz="0.276 0 0.181" rpy="0 0.18 0"/>
    </joint>
 
    <link name="camera_link">
        <visual>
            <geometry>
                <box size="0.010 0.03 0.03"/>
            </geometry>
            <material name="black"/>
        </visual>
        <visual>
            <origin xyz="0 0 -0.05"/>
            <geometry>
                <cylinder radius="0.002" length="0.1"/>
            </geometry>
            <material name="black"/>
        </visual>
    </link>
 
 
    <joint name="camera_optical_joint" type="fixed">
        <parent link="camera_link"/>
        <child link="camera_link_optical"/>
        <origin xyz="0 0 0" rpy="${-pi/2} 0 ${-pi/2}"/>
    </joint>
 
    <link name="camera_link_optical"></link>
 
 
 
    <gazebo reference="camera_link">
        <material>Gazebo/Black</material>
 
        <sensor name="camera" type="camera">
            <pose> 0 0 0 0 0 0 </pose>
            <visualize>true</visualize>
            <update_rate>10</update_rate>
            <camera>
                <camera_info_topic>camera/camera_info</camera_info_topic>
                <horizontal_fov>1.089</horizontal_fov>
                <image>
                    <format>R8G8B8</format>
                    <width>640</width>
                    <height>480</height>
                </image>
                <clip>
                    <near>0.05</near>
                    <far>8.0</far>
                </clip>
            </camera>
            <topic>camera/image_raw</topic>
            <gz_frame_id>camera_link_optical</gz_frame_id>
        </sensor>
    </gazebo>
 
</robot>

• Test image topic

ros2 topic echo /camera/image_raw

header:
  stamp:
    sec: 142
    nanosec: 500000000
  frame_id: camera_link_optical
height: 480
width: 640
encoding: rgb8
is_bigendian: 0
step: 1920
data:
- 218
- 218
- 218
- 218
- 218
- 218
- 218
...

ros_gz_bridge

• https://index.ros.org/p/ros_gz_bridge/

• Fix gz_topic_name error

gz-bridge.yaml

- ros_topic_name: "clock"
  gz_topic_name: "clock"
  ros_type_name: "rosgraph_msgs/msg/Clock"
  gz_type_name: "gz.msgs.Clock"
  direction: GZ_TO_ROS
 
  # gz topic published by Sensors plugin
- ros_topic_name: "scan"
  gz_topic_name: "lidar" # Fixed gz_topic_name
  ros_type_name: "sensor_msgs/msg/LaserScan"
  gz_type_name: "gz.msgs.LaserScan"
  direction: GZ_TO_ROS
 
  # gz topic published by Sensors plugin (Camera)
- ros_topic_name: "camera/camera_info"
  gz_topic_name: "camera/camera_info"
  ros_type_name: "sensor_msgs/msg/CameraInfo"
  gz_type_name: "gz.msgs.CameraInfo"
  direction: GZ_TO_ROS
 
 
# gz topic published by DiffDrive plugin
- ros_topic_name: "odom"
  gz_topic_name: "odom"
  ros_type_name: "nav_msgs/msg/Odometry"
  gz_type_name: "gz.msgs.Odometry"
  direction: GZ_TO_ROS
 
# gz topic published by JointState plugin
- ros_topic_name: "/joint_states"
  gz_topic_name: "/world/empty/model/my_bot/joint_state" # Fixed gz_topic_name
  ros_type_name: "sensor_msgs/msg/JointState"
  gz_type_name: "gz.msgs.Model"
  direction: GZ_TO_ROS
 
  # gz topic published by DiffDrive plugin
- ros_topic_name: "tf"
  gz_topic_name: "tf"
  ros_type_name: "tf2_msgs/msg/TFMessage"
  gz_type_name: "gz.msgs.Pose_V"
  direction: GZ_TO_ROS
 
- ros_topic_name: "/cmd_vel"
  gz_topic_name: "/model/my_bot/cmd_vel" # Fixed gz_topic_name
  ros_type_name: "geometry_msgs/msg/Twist"
  gz_type_name: "gz.msgs.Twist"
  direction: ROS_TO_GZ
 
#   # gz topic subscribed to by DiffDrive plugin
# - ros_topic_name: "diff_cont/cmd_vel_unstamped"
#   gz_topic_name: "cmd_vel"
#   ros_type_name: "geometry_msgs/msg/Twist"
#   gz_type_name: "gz.msgs.Twist"
#   direction: ROS_TO_GZs

Launch file

launch/launch_sim.launch.py

import os
 
from ament_index_python.packages import get_package_share_directory
 
from launch import LaunchDescription
from launch.actions import IncludeLaunchDescription, DeclareLaunchArgument
from launch.launch_description_sources import PythonLaunchDescriptionSource
from launch.substitutions import LaunchConfiguration
 
from launch_ros.actions import Node
 
def generate_launch_description():
    package_name='differential_drive_robot'
 
    rsp = IncludeLaunchDescription(
                PythonLaunchDescriptionSource([os.path.join(
                    get_package_share_directory(package_name),'launch','rsp.launch.py'
                )]), launch_arguments={'use_sim_time': 'true'}.items()
    )
 
    default_world = os.path.join(
	get_package_share_directory(package_name),
	'worlds',
	'obstacle_world.sdf'
    # 'empty.world'
    )
 
    world = LaunchConfiguration('world')
 
    world_arg = DeclareLaunchArgument(
        'world',
        default_value=default_world,
        description='World to load'
    )
 
    # Include the Gazebo launch file, provided by the ros_gz_sim package
    gazebo = IncludeLaunchDescription(
                PythonLaunchDescriptionSource([os.path.join(
                    get_package_share_directory('ros_gz_sim'), 'launch', 'gz_sim.launch.py')]),
                    launch_arguments={'gz_args': ['-r -v4 ', world], 'on_exit_shutdown': 'true'}.items()
             )
 
    # Run the spawner node from the ros_gz_sim package
    spawn_entity = Node(package='ros_gz_sim', executable='create',
                        arguments=['-topic', 'robot_description',
                                   '-name', 'my_bot',
                                   '-z', '0.1'],
                        output='screen')
 
    # # Bridge for cmd_vel and other topics
    # bridge = Node(
    #     package='ros_gz_bridge',
    #     executable='parameter_bridge',
    #     parameters=[{
    #         'config_file': os.path.join(get_package_share_directory(package_name), 'config', 'bridge.yaml'),
    #     }],
    #     output='screen'
    # )
 
    bridge_params = os.path.join(get_package_share_directory(package_name),'config','gz_bridge.yaml')
    ros_gz_bridge = Node(
        package="ros_gz_bridge",
        executable="parameter_bridge",
        arguments=[
            '--ros-args',
            '-p',
            f'config_file:={bridge_params}',
        ]
    )
 
    ros_gz_image_bridge = Node(
        package="ros_gz_image",
        executable="image_bridge",
        arguments=["/camera/image_raw"]
    )
 
    # Launch them all!
    return LaunchDescription([
        rsp,
        world_arg,
        gazebo,
        spawn_entity,
        ros_gz_bridge,
        ros_gz_image_bridge
    ])
 

Run simulation

• Update obstacle_worlds.sdf to include sensor plugins

  <plugin
       filename="gz-sim-sensors-system"
       name="gz::sim::systems::Sensors">
       <render_engine>ogre2</render_engine>
     </plugin>
 
- Drive the robot
```bash
ros2 run teleop_twist_keyboard teleop_twist_keyboard

• List gazebo topics

 gz topic -l

/camera/camera_info
/camera/image_raw
/clock
/gazebo/resource_paths
/gui/camera/pose
/gui/record_video/stats
/keyboard/keypress
/model/my_bot/cmd_vel
/model/my_bot/joint_state
/model/my_bot/odometry
/model/my_bot/tf
/scan
/scan/points
/sensors/marker
/stats
/world/empty/clock
/world/empty/dynamic_pose/info
/world/empty/pose/info
/world/empty/scene/deletion
/world/empty/scene/info
/world/empty/state
/world/empty/stats

• List ros topics

ros2 topic list

/camera/camera_info
/camera/image_raw
/camera/image_raw/compressed
/camera/image_raw/compressedDepth
/camera/image_raw/theora
/clock
/cmd_vel
/joint_states
/odom
/parameter_events
/robot_description
/rosout
/scan
/tf
/tf_static

Fix wheel joint issue

• https://github.com/Training-Dummy/diff_drive_robot

• Drive the

ros2 run teleop_twist_keyboard teleop_twist_keyboard

RViz

• Update diff-drive.rviz

diff-drive.rviz

Panels:
  - Class: rviz_common/Displays
    Help Height: 78
    Name: Displays
    Property Tree Widget:
      Expanded:
        - /Global Options1
        - /Status1
        - /RobotModel1/Description Topic1
        - /TF1
        - /LaserScan1
        - /Image1
        - /Image1/Topic1
      Splitter Ratio: 0.5
    Tree Height: 433
  - Class: rviz_common/Selection
    Name: Selection
  - Class: rviz_common/Tool Properties
    Expanded:
      - /2D Goal Pose1
      - /Publish Point1
    Name: Tool Properties
    Splitter Ratio: 0.5886790156364441
  - Class: rviz_common/Views
    Expanded:
      - /Current View1
    Name: Views
    Splitter Ratio: 0.5
  - Class: rviz_common/Time
    Experimental: false
    Name: Time
    SyncMode: 0
    SyncSource: ""
Visualization Manager:
  Class: ""
  Displays:
    - Alpha: 0.5
      Cell Size: 1
      Class: rviz_default_plugins/Grid
      Color: 160; 160; 164
      Enabled: true
      Line Style:
        Line Width: 0.029999999329447746
        Value: Lines
      Name: Grid
      Normal Cell Count: 0
      Offset:
        X: 0
        Y: 0
        Z: 0
      Plane: XY
      Plane Cell Count: 10
      Reference Frame: <Fixed Frame>
      Value: true
    - Alpha: 1
      Class: rviz_default_plugins/RobotModel
      Collision Enabled: false
      Description File: ""
      Description Source: Topic
      Description Topic:
        Depth: 5
        Durability Policy: Volatile
        History Policy: Keep Last
        Reliability Policy: Reliable
        Value: /robot_description
      Enabled: true
      Links:
        All Links Enabled: true
        Expand Joint Details: false
        Expand Link Details: false
        Expand Tree: false
        Link Tree Style: Links in Alphabetic Order
        base_link:
          Alpha: 1
          Show Axes: false
          Show Trail: false
        camera_link:
          Alpha: 1
          Show Axes: false
          Show Trail: false
          Value: true
        camera_link_optical:
          Alpha: 1
          Show Axes: false
          Show Trail: false
        caster_wheel:
          Alpha: 1
          Show Axes: false
          Show Trail: false
          Value: true
        chassis:
          Alpha: 1
          Show Axes: false
          Show Trail: false
          Value: true
        laser_frame:
          Alpha: 1
          Show Axes: false
          Show Trail: false
          Value: true
        left_wheel:
          Alpha: 1
          Show Axes: false
          Show Trail: false
          Value: true
        right_wheel:
          Alpha: 1
          Show Axes: false
          Show Trail: false
          Value: true
      Mass Properties:
        Inertia: false
        Mass: false
      Name: RobotModel
      TF Prefix: ""
      Update Interval: 0
      Value: true
      Visual Enabled: true
    - Class: rviz_default_plugins/TF
      Enabled: true
      Frame Timeout: 15
      Frames:
        All Enabled: true
        base_link:
          Value: true
        camera_link:
          Value: true
        camera_link_optical:
          Value: true
        caster_wheel:
          Value: true
        chassis:
          Value: true
        laser_frame:
          Value: true
      Marker Scale: 1
      Name: TF
      Show Arrows: true
      Show Axes: true
      Show Names: true
      Tree:
        base_link:
          chassis:
            camera_link:
              camera_link_optical:
                {}
            caster_wheel:
              {}
            laser_frame:
              {}
      Update Interval: 0
      Value: true
    - Alpha: 1
      Autocompute Intensity Bounds: true
      Autocompute Value Bounds:
        Max Value: 10
        Min Value: -10
        Value: true
      Axis: Z
      Channel Name: intensity
      Class: rviz_default_plugins/LaserScan
      Color: 255; 255; 255
      Color Transformer: ""
      Decay Time: 0
      Enabled: true
      Invert Rainbow: false
      Max Color: 255; 255; 255
      Max Intensity: 4096
      Min Color: 0; 0; 0
      Min Intensity: 0
      Name: LaserScan
      Position Transformer: ""
      Selectable: true
      Size (Pixels): 3
      Size (m): 0.009999999776482582
      Style: Flat Squares
      Topic:
        Depth: 5
        Durability Policy: Volatile
        Filter size: 10
        History Policy: Keep Last
        Reliability Policy: Reliable
        Value: /scan
      Use Fixed Frame: true
      Use rainbow: true
      Value: true
    - Class: rviz_default_plugins/Image
      Enabled: true
      Max Value: 1
      Median window: 5
      Min Value: 0
      Name: Image
      Normalize Range: true
      Topic:
        Depth: 5
        Durability Policy: Volatile
        History Policy: Keep Last
        Reliability Policy: Reliable
        Value: /camera/image_raw
      Value: true
  Enabled: true
  Global Options:
    Background Color: 48; 48; 48
    Fixed Frame: base_link
    Frame Rate: 30
  Name: root
  Tools:
    - Class: rviz_default_plugins/Interact
      Hide Inactive Objects: true
    - Class: rviz_default_plugins/MoveCamera
    - Class: rviz_default_plugins/Select
    - Class: rviz_default_plugins/FocusCamera
    - Class: rviz_default_plugins/Measure
      Line color: 128; 128; 0
    - Class: rviz_default_plugins/SetInitialPose
      Covariance x: 0.25
      Covariance y: 0.25
      Covariance yaw: 0.06853891909122467
      Topic:
        Depth: 5
        Durability Policy: Volatile
        History Policy: Keep Last
        Reliability Policy: Reliable
        Value: /initialpose
    - Class: rviz_default_plugins/SetGoal
      Topic:
        Depth: 5
        Durability Policy: Volatile
        History Policy: Keep Last
        Reliability Policy: Reliable
        Value: /goal_pose
    - Class: rviz_default_plugins/PublishPoint
      Single click: true
      Topic:
        Depth: 5
        Durability Policy: Volatile
        History Policy: Keep Last
        Reliability Policy: Reliable
        Value: /clicked_point
  Transformation:
    Current:
      Class: rviz_default_plugins/TF
  Value: true
  Views:
    Current:
      Class: rviz_default_plugins/Orbit
      Distance: 8.984903335571289
      Enable Stereo Rendering:
        Stereo Eye Separation: 0.05999999865889549
        Stereo Focal Distance: 1
        Swap Stereo Eyes: false
        Value: false
      Focal Point:
        X: 0.05397603660821915
        Y: 0.08794327825307846
        Z: 0.05943708494305611
      Focal Shape Fixed Size: true
      Focal Shape Size: 0.05000000074505806
      Invert Z Axis: false
      Name: Current View
      Near Clip Distance: 0.009999999776482582
      Pitch: 0.22020354866981506
      Target Frame: <Fixed Frame>
      Value: Orbit (rviz)
      Yaw: 2.755408763885498
    Saved: ~
Window Geometry:
  Displays:
    collapsed: false
  Height: 987
  Hide Left Dock: false
  Hide Right Dock: false
  Image:
    collapsed: false
  QMainWindow State: 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
  Selection:
    collapsed: false
  Time:
    collapsed: false
  Tool Properties:
    collapsed: false
  Views:
    collapsed: false
  Width: 1908
  X: 0
  Y: 0
 

• Run RViz

rviz2 -d src/differential_drive_robot/config/diff-drive.rviz