Added README.md for dummy_robot_bringup. (#574)

Signed-off-by: Bey Hao Yun <[email protected]>
Signed-off-by: Alejandro Hernández Cordero <[email protected]>
Signed-off-by: Alejandro Hernandez Cordero <[email protected]>
Co-authored-by: Alejandro Hernández Cordero <[email protected]>

Author: cardboardcode

dummy_robot/dummy_robot_bringup/CMakeLists.txt

@@ -4,7 +4,7 @@ project(dummy_robot_bringup)
 
 find_package(ament_cmake REQUIRED)
 
-install(DIRECTORY launch
+install(DIRECTORY launch rviz
   DESTINATION share/${PROJECT_NAME})
 
 if(BUILD_TESTING)

dummy_robot/dummy_robot_bringup/README.md

@@ -0,0 +1,76 @@
+## **What Is This?**
+
+This is a simple demo robot with all components from publishing **joint states** to publishing **fake laser data** to visualizing the robot model on a map in `RViz2`.
+
+## **Build**
+
+```bash
+colcon build --package-select dummy_map_server dummy_sensors dummy_robot_bringup
+```
+
+## **Run**
+
+```bash
+ros2 launch dummy_robot_bringup dummy_robot_bringup_launch.py
+```
+
+## **Verify**
+
+A similar terminal output should be seen:
+
+```bash
+[INFO] [launch]: All log files can be found below /home/$USER/.ros/log/2022-07-22-17-02-33-629155-comname-39641
+[INFO] [launch]: Default logging verbosity is set to INFO
+[INFO] [dummy_map_server-1]: process started with pid [39643]
+[INFO] [robot_state_publisher-2]: process started with pid [39645]
+[INFO] [dummy_joint_states-3]: process started with pid [39647]
+[INFO] [dummy_laser-4]: process started with pid [39649]
+[dummy_laser-4] [INFO] [1658480554.018685559] [dummy_laser]: angle inc:	0.004363
+[dummy_laser-4] [INFO] [1658480554.018738346] [dummy_laser]: scan size:	1081
+[dummy_laser-4] [INFO] [1658480554.018747091] [dummy_laser]: scan time increment: 0.000028
+[robot_state_publisher-2] Link single_rrbot_link1 had 1 children
+[robot_state_publisher-2] Link single_rrbot_link2 had 1 children
+[robot_state_publisher-2] Link single_rrbot_link3 had 2 children
+[robot_state_publisher-2] Link single_rrbot_camera_link had 0 children
+[robot_state_publisher-2] Link single_rrbot_hokuyo_link had 0 children
+[robot_state_publisher-2] [INFO] [1658480554.019739425] [robot_state_publisher]: got segment single_rrbot_camera_link
+[robot_state_publisher-2] [INFO] [1658480554.019783457] [robot_state_publisher]: got segment single_rrbot_hokuyo_link
+[robot_state_publisher-2] [INFO] [1658480554.019791344] [robot_state_publisher]: got segment single_rrbot_link1
+[robot_state_publisher-2] [INFO] [1658480554.019796905] [robot_state_publisher]: got segment single_rrbot_link2
+[robot_state_publisher-2] [INFO] [1658480554.019801861] [robot_state_publisher]: got segment single_rrbot_link3
+[robot_state_publisher-2] [INFO] [1658480554.019806522] [robot_state_publisher]: got segment world
+```
+
+The robot should be displayed similarly in `RViz2`:
+
+![](img/robot_in_rviz.gif)
+
+## **FAQ**
+
+`Q`: I ran `ros2 launch dummy_robot_bringup dummy_robot_bringup_launch.py` and `rviz2`. However, nothing is displayed in `RViz2` window.
+
+`A`: This issue could be related to the **ROS 2 Daemon**. It serves the same role as a **ROS1 Master** but within **ROS 2**. Restarting the daemon, as follows, should resolve this issue.
+
+`Reference`: https://github.com/ros2/ros2cli/issues/582#issuecomment-775997721
+
+```bash
+ros2 daemon stop; ros2 daemon start
+# Verify
+# Open new terminal
+ros2 launch dummy_robot_bringup dummy_robot_bringup_launch.py
+# Open new terminal
+ros2 node list
+```
+
+```bash
+# You should see the following terminal output:
+/dummy_joint_states
+/dummy_laser
+/dummy_map_server
+/robot_state_publisher
+```
+
+## **References**
+
+- Original Rolling Demo Tutorial: https://docs.ros.org/en/rolling/Tutorials/Demos/dummy-robot-demo.html
+- What is ROS 2 Daemon: https://answers.ros.org/question/327348/what-is-ros2-daemon/

dummy_robot/dummy_robot_bringup/config/dummy_robot.rviz

@@ -15,13 +15,16 @@
 import os
 
 from launch import LaunchDescription
-from launch.substitutions import FileContent
 from launch_ros.actions import Node
-from launch_ros.substitutions import FindPackageShare
+from launch_ros.substitutions import FileContent, FindPackageShare
 
 
 def generate_launch_description():
+
     pkg_share = FindPackageShare('dummy_robot_bringup').find('dummy_robot_bringup')
+
+    default_rviz_config_path = os.path.join(pkg_share, 'rviz/dummy_robot.rviz')
+
     urdf_file = os.path.join(pkg_share, 'launch', 'single_rrbot.urdf')
     robot_desc = FileContent(urdf_file)
     rsp_params = {'robot_description': robot_desc}
@@ -31,5 +34,8 @@ def generate_launch_description():
         Node(package='robot_state_publisher', executable='robot_state_publisher',
              output='screen', parameters=[rsp_params]),
         Node(package='dummy_sensors', executable='dummy_joint_states', output='screen'),
-        Node(package='dummy_sensors', executable='dummy_laser', output='screen')
+        Node(package='dummy_sensors', executable='dummy_laser', output='screen'),
+        Node(package='rviz2', executable='rviz2', name='rviz2', output='screen',
+             arguments=['-d', default_rviz_config_path])
+
     ])

dummy_robot/dummy_robot_bringup/img/robot_in_rviz.gif

@@ -23,6 +23,7 @@
   <exec_depend>launch</exec_depend>
   <exec_depend>launch_ros</exec_depend>
   <exec_depend>robot_state_publisher</exec_depend>
+  <exec_depend>rviz2</exec_depend>
 
   <test_depend>ament_cmake_gtest</test_depend>
   <test_depend>ament_lint_auto</test_depend>