gwendolen-rosbridge

Gwendolen environment that allows agents to publish/subscribe to ROS topics using rosbridge.

Works for all ROS 1 and ROS 2 distros that support the rosbridge library.

We are using the java_rosbridge library to connect to rosbridge using Java code.

To test:

1. Install MCAPL using the Eclipse method, and make sure it is working
2. Install ROS, any version, and make sure it is working
3. Install Rosbridge for the ROS version that you installed (and make sure it is working!)
4. Copy lib/3rdparty/java_rosbridge_all.jar to lib/3rdparty folder in MCAPL
5. Edit .classpath found in the root of MCAPL, and add the line <classpathentry kind="lib" path="lib/3rdparty/java_rosbridge_all.jar"/>
   • Make sure you refresh the project if using Eclipse. Otherwise if this does not work, it may be necessary to add the above jar to the project dependencies manually in the Eclipse properties if using Eclipse, or in the build.xml (from the root folder of MCAPL) if using from the command line
6. Copy the src/examples/gwendolen/ros folder to MCAPL root
7. Start ROS with rosbridge in a terminal using:
   • For ROS 1: roslaunch rosbridge_server rosbridge_websocket.launch
   • For ROS 2: ros2 launch rosbridge_server rosbridge_websocket_launch.xml
8. In Eclipse, go to src/examples/gwendolen/ros, right-click hello.ail, select run as > run configurations, type run-AIL in the search box (should be there if MCAPL was installed correctly), and click on run
   • You should see the messages from Gwendolen agents in the terminal from step 6
9. Open another terminal (remember to source your ROS distro) and use the command (this is where messages from Gwendolen will appear):
   • For ROS 1: rostopic echo /java_to_ros
   • For ROS 2: ros2 topic echo /java_to_ros
10. To test the subscriber, open another terminal and type:

• For ROS 1: rostopic pub ros_to_java std_msgs/String "hello from ros"
• For ROS 2: ros2 topic pub /ros_to_java std_msgs/String "data: hello from ros"
• You should see "hello from ros" in the Eclipse terminal

If you require extra message types, clone the code from java_rosbridge, add the messages you require (src/ros/msgs), run mvn package and copy the newly generated jar target/java_rosbridge-2.0.2-jar-with-dependencies.jar to lib/3rdparty folder in MCAPL, rename it to java_rosbridge_all.jar and overwrite it.

Message types available in the current jar:

• actionlib_msgs: GoalId (Time stamp, String id)
• geometry_msgs: Twist (Vector3 linear, Vector3 angular)
• geometry_msgs: Vector3 (double x, double y, double z)
• move_base_msgs: MoveBaseActionResult (Header header, Status status, Result result)
• move_base_msgs: Result ()
• move_base_msgs: Status (GoalId goal_id, String status, String text)
• sensor_msgs: Image(Header header, int height, int width, String encoding, int is_bigendian, int step, byte[] data)
• std_msgs: Header(int seq, Time stamp, String frame_id)
• std_msgs: PrimitiveMsg(data)
• std_msgs: Time(int secs, int nsecs)