Cleanup code and use composable nodes for Gazebo

doc/index.rst

@@ -133,7 +133,7 @@ URDF:
 .. code-block:: xml
 
   <gazebo>
-    <plugin filename="libgz_ros2_control-system.so" name="gz_ros2_control::GazeboSimROS2ControlPlugin">
+    <plugin filename="gz_ros2_control-system" name="gz_ros2_control::GazeboSimROS2ControlPlugin">
       <parameters>$(find gz_ros2_control_demos)/config/cart_controller.yaml</parameters>
     </plugin>
   </gazebo>
@@ -142,7 +142,7 @@ SDF:
 
 .. code-block:: xml
 
-  <plugin filename="libgz_ros2_control-system.so" name="gz_ros2_control::GazeboSimROS2ControlPlugin">
+  <plugin filename="gz_ros2_control-system.so" name="gz_ros2_control::GazeboSimROS2ControlPlugin">
     <parameters>$(find gz_ros2_control_demos)/config/cart_controller.yaml</parameters>
   </plugin>
 
@@ -172,7 +172,7 @@ URDF:
 .. code-block:: xml
 
   <gazebo>
-    <plugin filename="libgz_ros2_control-system.so" name="gz_ros2_control::GazeboSimROS2ControlPlugin">
+    <plugin filename="gz_ros2_control-system" name="gz_ros2_control::GazeboSimROS2ControlPlugin">
       ...
       <ros>
         <namespace>my_namespace</namespace>
@@ -185,7 +185,7 @@ SDF:
 
 .. code-block:: xml
 
-  <plugin filename="libgz_ros2_control-system.so" name="gz_ros2_control::GazeboSimROS2ControlPlugin">
+  <plugin filename="gz_ros2_control-system" name="gz_ros2_control::GazeboSimROS2ControlPlugin">
     ...
     <ros>
       <namespace>my_namespace</namespace>
@@ -226,7 +226,7 @@ URDF:
     ...
   <ros2_control>
   <gazebo>
-    <plugin name="gz_ros2_control::GazeboSimROS2ControlPlugin" filename="libgz_ros2_control-system">
+    <plugin name="gz_ros2_control::GazeboSimROS2ControlPlugin" filename="gz_ros2_control-system">
       ...
     </plugin>
   </gazebo>
@@ -241,7 +241,7 @@ SDF:
     </hardware>
     ...
   <ros2_control>
-  <plugin name="gz_ros2_control::GazeboSimROS2ControlPlugin" filename="libgz_ros2_control-system">
+  <plugin name="gz_ros2_control::GazeboSimROS2ControlPlugin" filename="gz_ros2_control-system">
     ...
   </plugin>
 
@@ -327,14 +327,38 @@ You can run some of the mobile robots running the following commands:
   ros2 launch gz_ros2_control_demos diff_drive_example.launch.py
   ros2 launch gz_ros2_control_demos tricycle_drive_example.launch.py
   ros2 launch gz_ros2_control_demos ackermann_drive_example.launch.py
+  ros2 launch gz_ros2_control_demos mecanum_drive_example.launch.py
+
+When the Gazebo world is launched you can run the following command to move the robots.
+
+.. code-block:: shell
+
+  ros2 run gz_ros2_control_demos example_mobile_robots
+
+You can also drive the robots from the keyboard using the following command:
+
+.. code-block:: shell
+
+  ros2 run teleop_twist_keyboard teleop_twist_keyboard --ros-args -p stamped:=true
 
-When the Gazebo world is launched you can run some of the following commands to move the robots.
+You can also manually publish on the ``/cmd_vel`` topic to drive the robots:
 
 .. code-block:: shell
 
-  ros2 run gz_ros2_control_demos example_diff_drive
-  ros2 run gz_ros2_control_demos example_tricycle_drive
-  ros2 run gz_ros2_control_demos example_ackermann_drive
+  ros2 topic pub --rate 10 /cmd_vel geometry_msgs/msg/TwistStamped "
+  twist:
+    linear:
+      x: 0.7
+      y: 0.0
+      z: 0.0
+    angular:
+      x: 0.0
+      y: 0.0
+      z: 1.0"
+
+For these demos you can verify that the robot is moving at the desired velocities be echoing the ``/gz/odom`` topic.
+This topic gets the simulation-real odometry of the robot from Gazebo.
+You can also echo the ``<controller_name>/odom`` topic to verify how accurate the odometry calculated by the controller is in comparison to the odometry from ``/gz/odom``.
 
 To demonstrate the setup of a namespaced robot, run
 
@@ -348,13 +372,6 @@ which will launch a diff drive robot within the namespace ``r1``.
 
   The ros2_control settings for the controller_manager and the controller defined in ``diff_drive_controller.yaml`` use wildcards to match all namespaces.
 
-To run the Mecanum mobile robot run the following commands to drive it from the keyboard:
-
-.. code-block:: shell
-
-  ros2 launch gz_ros2_control_demos mecanum_drive_example.launch.py
-  ros2 run teleop_twist_keyboard teleop_twist_keyboard --ros-args -p stamped:=true
-
 Gripper
 -----------------------------------------------------------
 

gz_ros2_control_demos/config/diff_drive_controller.yaml

@@ -5,14 +5,13 @@
     joint_state_broadcaster:
       type: joint_state_broadcaster/JointStateBroadcaster
 
-/**/diff_drive_base_controller:
+/**/diff_drive_controller:
   ros__parameters:
     type: diff_drive_controller/DiffDriveController
     left_wheel_names: ["left_wheel_joint"]
     right_wheel_names: ["right_wheel_joint"]
 
     wheel_separation: 1.25
-    #wheels_per_side: 1  # actually 2, but both are controlled by 1 signal
     wheel_radius: 0.3
 
     wheel_separation_multiplier: 1.0
@@ -29,8 +28,8 @@
     enable_odom_tf: true
 
     cmd_vel_timeout: 0.5
-    #publish_limited_velocity: true
-    #velocity_rolling_window_size: 10
+    publish_limited_velocity: true
+    velocity_rolling_window_size: 10
 
     # Velocity and acceleration limits
     # Whenever a min_* is unspecified, default to -max_*

gz_ros2_control_demos/config/ros_gz_bridge_config.yaml

@@ -0,0 +1,13 @@
+---
+- 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
+
+# Topic published by OdometryPublisher plugin, only for debugging purposes
+- ros_topic_name: "/gz/odom"
+  gz_topic_name: "/gz/odom"
+  ros_type_name: "nav_msgs/msg/Odometry"
+  gz_type_name: "gz.msgs.Odometry"
+  direction: GZ_TO_ROS

gz_ros2_control_demos/examples/example_diff_drive.cpp → gz_ros2_control_demos/examples/example_mobile_robots.cpp

@@ -25,10 +25,10 @@ int main(int argc, char * argv[])
   rclcpp::init(argc, argv);
 
   std::shared_ptr<rclcpp::Node> node =
-    std::make_shared<rclcpp::Node>("diff_drive_test_node");
+    std::make_shared<rclcpp::Node>("example_mobile_robots_node");
 
   auto publisher = node->create_publisher<geometry_msgs::msg::TwistStamped>(
-    "/diff_drive_base_controller/cmd_vel", 10);
+    "/cmd_vel", 10);
 
   RCLCPP_INFO(node->get_logger(), "node created");