xbot2_examples

Examples for the XBot2.0 middleware

This repository containes commented examples of use for the XBot2.0 real-time middleware for robotics. The IIT-Teleop robot, a 5-dof robotic arm, is provided as testing platform. Follow the link and install the framework before you go ahead!

Contents

• Simulating a robotic system with Gazebo
• Writing a simple control module as an XBot2 Plugin
• Configuring the middleware
• Inter-plugin communication (data streaming, rpc-like)
• Using ROS from a real-time plugin
• Adding a custom device
• Controlling the robot from ROS

How to build

Standard CMake workflow

• mkdir build && cd build
• ccmake <path-to-repo>
• select a build type and an install folder (must be visible to the dynamic linker), type c and then g
• make -j install
• sudo ldconfig might be required if installing to /usr/local

## How to setup

• make sure that the robot sdf and meshes are visible to Gazebo; for instance, you can add the following line to your .bashrc export GAZEBO_MODEL_PATH=$GAZEBO_MODEL_PATH:<path-to-repo>/models/database
  • set the XBot2 configuration file to the provided example with set_xbot2_config <path-to-repo>/config/teleop_simple_example.yaml (note: this is optional as this information can be provided later as a command line argument)

Note: a more complete teleop_complete_example.yaml is available, too; it requires to enable the XBOT2_EXAMPLES_WITH_GZ flag during compilation.

## How to run

• load the provided .world file to Gazebo with the following command: gazebo <path-to-repo>/world/teleop_xbot2.world you should now see the robot inside Gazebo; a simple bash script <path-to-repo>/run_simulation.bash provides a shorthand for this command.
• run XBot2 with xbot2-core or xbot2-core --verbose (note: add --config <path-to-repo>/config/teleop_simple_example.yaml if you did not use the set_xbot2_config command during the setup phase)

You should now be able to (for instance)

• get the list of loaded plugins -> rosservice call /xbotcore/get_plugin_list
• monitor execution time -> rostopic echo /xbotcore/statistics
• monitor joint state -> rostopic echo /xbotcore/joint_states

Running inside Docker container

• install docker and set it up so that it does not require sudo permissions
• install nvidia container toolkit if you have an nvidia card
• ./docker/run.sh runs the container (the first time it will also download a crazy amount of data!)
• to spawn more bash sessions inside the same container instance, do ./docker/attach.sh
• open three bash sessions
• terminal #1: ./start.sh (starts roscore and gazebo)
• terminal #2: xbot2-core (XBot2 executable)
• terminal #3: xbot2-gui (GUI should appear)