ROS is a set of well-engineered software libraries for building robotics applications. It includes a wide variety of packages, from low level drivers to efficient implementations of state of the art algorithms. As we strive to build intelligent agents and transfer them to real-world (on a real robot), we need to take advantage of ROS packages to complete the robot application pipeline.
There are three key applications of integrating iGibson with ROS.
Benchmark existing algorithms in a controlled realistic simulation environment. This allows for comparing learning-based methods with classical methods in simulation environments.
Comparing robots in simulation with robots in the real world. In simulation, iGibson can simulate sensors of a robot and publish as messages. In the real world, a real robot publish sensor messages from onboard sensors. Therefore, it is possible to only change the message subscribed and benchmark the performance of downstream applications. This helps locate domain gap and debug algorithms.
Using ROS functions in simulation, such as many motion planning implementations.
The possibility of using iGibson with ROS is unlimited. As a starter, we provide an example of integrating iGibson with ROS for navigation. This is a ROS package integrates iGibson Env with ROS navigation stack. It follows the same node topology and topics as
turtlebot_navigation package. As shown below, so after a policy is trained in iGibson, it requires minimal changes to deploy onto a real turtlebot.
Install ROS: in this package, we use navigation stack from ROS kinetic. Please follow the instructions.
Install iGibson from source following installation guide in python2.7. Note that ROS only supports
python2.7at the moment, so you need to create python2.7 virtual environment to install iGibson instead of python3.x.
git clone https://github.com/StanfordVL/iGibson --recursive cd iGibson conda create -n py2-igibson python=2.7 anaconda # we support python 2.7, 3.5, 3.6, 3.7, 3.8 source activate py2-igibson pip install -e . # This step takes about 4 minutes source deactivate # This step is important because we will NOT use <anaconda installation root>/envs/py2-igibson/bin/python
If you use anaconda for setting up python environment, some tweaks of
PYTHONPATHvariable are required to avoid conflict. In particular:
PATH: conda related needs to be removed from
echo $PATH | grep -oP "[^:;]+" | grep conda ## Remove these paths from $PATH
/opt/ros/kinetic/lib/python2.7/dist-packages(ROS python libraries),
<anaconda installation root>/envs/py2-igibson/lib/python2.7/site-packages(iGibson dependencies) and
<iGibson root>need to be in
PYTHONPATHin this exact order.
mkdir -p ~/catkin_ws
igibson-rosfolder to your
cd <iGibson root>/igibson ln -s $PWD/examples/ros/igibson-ros/ ~/catkin_ws/src/ cd ~/catkin_ws && catkin_make
cd ~/catkin_ws rosdep install --from-paths src --ignore-src -r -y
which python # Should give /usr/bin/python, NOT <anaconda installation root>/envs/py2-igibson/bin/python python -c 'import igibson, rospy, rospkg' # Should run without errors
In order to run iGibson+ROS examples, you will need to perform the following steps:
Prepare ROS environment
source /opt/ros/kinetic/setup.bash source ~/catkin_ws/devel/setup.bash
Repeat Step 3 from Preparation: sanitize
Here are some of the examples that you can run, including gmapping, hector mapping and navigation.
roslaunch igibson-ros turtlebot_rgbd.launch # Bare minimal bringup example roslaunch igibson-ros turtlebot_gmapping.launch # Run gmapping roslaunch igibson-ros turtlebot_hector_mapping.launch # Run hector mapping roslaunch igibson-ros turtlebot_navigation.launch # Run the navigation stack, we have provided the map roslaunch igibson-ros turtlebot_gt_navigation.launch # Run the navigation stack with ground truth localization
The following screenshot is captured when running the bare minimal bringup example.
The following screenshot is captured when running the gmapping example.
Here are all the topics that
turtlebot_rgbd.py publishes and subscribes.
||Camera parameters used in iGibson, same for depth and rgb|
||RGB image captured in iGibson|
||Depth image captured in iGibson, in meters, with dtype being float32|
||Depth image captured in iGibson, mimic raw depth data captured with OpenNI cameras, with dtype being uint16, see more here|
||1-beam LiDAR scan captured in iGibson, in meters, with dtype being float32|
||The pose of
||The pose of
||Velocity command for turtlebot,
||Direct reset turtlebot's pose (i.e. teleportation)|