$\newcommand{\d}{\mathrm{d}} \newcommand{\bff}{\boldsymbol{f}} \newcommand{\bfg}{\boldsymbol{g}} \newcommand{\bfp}{\boldsymbol{p}} \newcommand{\bfq}{\boldsymbol{q}} \newcommand{\bfx}{\boldsymbol{x}} \newcommand{\bfu}{\boldsymbol{u}} \newcommand{\bfv}{\boldsymbol{v}} \newcommand{\bfA}{\boldsymbol{A}} \newcommand{\bfB}{\boldsymbol{B}} \newcommand{\bfC}{\boldsymbol{C}} \newcommand{\bfM}{\boldsymbol{M}} \newcommand{\bfJ}{\boldsymbol{J}} \newcommand{\bfR}{\boldsymbol{R}} \newcommand{\bfT}{\boldsymbol{T}} \newcommand{\bfomega}{\boldsymbol{\omega}} \newcommand{\bftau}{\boldsymbol{\tau}}$

System: ROS, Gazebo

The Robot Operating System (ROS) is a flexible framework for writing and executing robot programs. It is a collection of tools, libraries, and conventions that aim to simplify the task of creating complex and robust robot behavior across a wide variety of robotic platforms.

ROS installation

Set-up your computer to accept software from packages.ros.org and set-up your keys following the steps described at http://wiki.ros.org/kinetic/Installation/Ubuntu

Now, install the ROS bare bones

command-line

# Installation
sudo apt-get update
sudo apt-get install python-wstool ros-kinetic-ros-base
# Initialize rosdep
sudo rosdep init
rosdep update

Create a ROS workspace

Let’s create a catkin workspace

command-line

source /opt/ros/kinetic/setup.bash
cd ~/catkin_ws/src
catkin_init_workspace

Even though the workspace is empty (there are no packages in the $\texttt{src}$ folder, just a single $\texttt{CMakeLists.txt}$ symbolic link) you can still build the workspace

command-line

cd ~/catkin_ws/
catkin_make

Before continuing, source your workspace $\texttt{setup.bash}$ file

command-line

source ~/catkin_ws/devel/setup.bash

To make sure your workspace is properly overlayed by the setup script, make sure ROS_PACKAGE_PATH environment variable includes the path to your workspace

command-line

echo $ROS_PACKAGE_PATH

This is the expected output

/home/USERNAME/catkin_ws/src:/opt/ros/kinetic/share

Configure your .bashrc

Every time you start a new terminal, the file ~/.bashrc will be sourced. When you already have an opened terminal, you can source it manually running this command

command-line

source ~/.bashrc

In order to use ROS, you need to source the ROS setup.bash file, therefore, it's recommended to include the previous command in your .bashrc file. You can do so by running this

command-line

echo "source ~/catkin_ws/devel/setup.bash" >> ~/.bashrc

Testing the installation

Let's try to run $\texttt{roscore}$ in a first terminal. Then, publish a $\texttt{std_msgs/String}$ message to the topic $\texttt{/some_topic_name}$ a second terminal. Finally, subscribe to the same topic and print it out the message in a third terminal:

command-line

# Terminal 1
roscore
# Terminal 2
rostopic pub -r 1 /some_topic_name std_msgs/String 'Hello World!'
# Terminal 3
rostopic echo /some_topic_name

ROS packages installation

For the sections where interaction with hardware components is required, we will simulate these components using Gazebo.

ROS packages from source

Go to the source folder of your ROS workspace

command-line

cd ~/catkin_ws/src

Make sure that you have cloned the course repository.

Now, use the $\texttt{wstool}$ to install required packages from source repositories

command-line

wstool init .
wstool merge osr_course_pkgs/dependencies.rosinstall
wstool update

Install any missing dependencies using rosdep

command-line

rosdep update
rosdep install --from-paths . --ignore-src -r -y

If rosdep is unable to install python-termcolor, install it manually

command-line

sudo apt-get install python-termcolor

Now compile your ROS workspace:

command-line

cd ~/catkin_ws && catkin_make install

Dependencies

rosdep is very useful to install system dependencies but those dependencies have to be included by the ROS community, therefore few packages need to be install manually:

command-line

# Packages from Ubuntu repositories
sudo apt-get install blender openscad python-rtree
# Python modules
pip install control trimesh --user

Testing the installation

Let's try visualizing the robot using RVIZ

command-line

roslaunch osr_description visualize_robot_gripper.launch

Play with the sliders to see how you can move the robot. This is a simple visualization where nothing is actually simulated. A simple test could be to move the robot to a configuration where it is in self-collision.

Finally, check that you can run the gazebo simulation:

command-line

roslaunch osr_gazebo robotic_setup.launch

gzserver --verbose

roslaunch osr_gazebo robotic_setup.launch gui:=false

To learn more about this topic

Take a look at the ROS Tutorials.