# Real-Time Robotics Framework

### Sidebar

getting_started:tutorials:hal4

# Using ROS through the HAL

EEROS can communicate with ROS through the HAL, see Interfacing with ROS.

In the EEROS library you will find a directory with examples. For this example see RosTest2.cpp.

Open a shell and run roscore. Open another shell in the build directory of your EEROS library and run

$sudo -E examples/ros/rosTest2 -c RosTest2Config.json ### Publishing This example runs your EEROS application as a ROS node under the name /eerosNode. It publishes three topics • /test/val (of type double) • /test/state (of type boolean) Use the same tools as in Control System Talking to ROS to show nodes, topics and messages. ### Subscribing Open another shell in the build directory of your EEROS library and run rosNodeTalker. This is not a EEROS program but simply starts a ROS node which publishes a couple of test topics. As soon as rosNodeTalker runs, your example application will receive the two topics • /rosNodeTalker/val (of type double) • /rosNodeTalker/state (of type boolean) and logs its transported message values into the console. Use$ rqt_graph

to show a graph with all involved nodes together with their topics.

### Another Example

There is another example, RosExample with HalConfigRos.json. It demonstrates the use of more message types.