simple_gazebo

simple_gazebo

ROS2 Crystal Clemmys introduces support for the 3D Simulation and Visualization tool Gazebo 9.

Differences with the ROS1 version here

Install

Install Gazebo More detailed instructions

$ wget https://bitbucket.org/osrf/release-tools/raw/default/one-line-installations/gazebo.sh
$ chmod +x gazebo.sh
$ ./gazebo.sh

Test if Gazebo is working

$ gazebo

Install from debian packages

If you are installing ROS2 from debian packages, you can easily do the same for gazebo.

$ sudo apt install -y  ros-crystal-vision-opencv ros-crystal-gazebo-ros-pkgs

Build from sources

On the other hand, if you are building from sources

Create a workspace for gazebo_ros_pkgs

$ mkdir -p ~/gazebo_ws/src
$ cd ~/gazebo_ws/src
$ git clone -b ros2 https://github.com/ros-simulation/gazebo_ros_pkgs
$ git clone -b ros2 https://github.com/ros-perception/vision_opencv
$ git clone -b ros2 https://github.com/ros-perception/image_common

Install other dependencies

$ cd ..
$ rosdep install --from-paths src --ignore-src -r -y

Build the workspace and source it

$ colcon build
$ source install/local_setup.sh

Usage

Now everything should be ready. You can run a Gazebo world file, as the example provided in the gazebo plugins package

$ gazebo --verbose /opt/ros/crystal/share/gazebo_plugins/worlds/gazebo_ros_diff_drive_demo.world

Now you should be able to see the ROS2 topics used by this example

$ ros2 topic list

For example, to send a velocity command to the robot

$ ros2 topic pub /demo/cmd_demo geometry_msgs/Twist '{linear: {x: 1.0}}' -1

If you want to change the settings for this simulation example, just edit its related world file

$ gedit /opt/ros/crystal/share/gazebo_plugins/worlds/gazebo_ros_diff_drive_demo.world

Troubleshooting

[Err] [Master.cc:96] EXCEPTION: Unable to start server[bind: Address already in use]. There is probably another Gazebo process running.

Kill all the gazebo-related processes:

$ pkill -9 gazebo
$ pkill -9 gzserver
$ pkill -9 gzclient