UR5 Controller Singularity

Figure 1: UR5 Robot with Ridgeback in OpenRAVE within a Singularity container with Ubuntu 14.04 and ROS Indigo. The host operating system is Ubuntu 18.04.

Developers and Contributors

UR5Controller Singularity was developed by the Robot Manipulation Lab in the School of Computing at the University of Leeds.

• Author: Rafael Papallas, Wissam Bejjani.
• Current maintainor: Rafael Papallas, Wissam Bejjani.

License

UR5Controller Singularity is licensed under GNU General Public License v3.0. The full license is available here.

Instructions

This is a Singularity container for ur5controller package.

Clone and build the singularity:

git clone https://github.com/roboticsleeds/ur5controller_singularity
cd ur5controller_singularity
./build.sh

This should create a local Ubuntu 14.04 file system with ROS Indigo, or\_urdf, and ur5controller in it.

It will take a while to build (approximately 40 minutes). Once built, you will automatically enter into the singualrity environment (which will build your catkin workspace).

When you need to enter your singularity environment, simply run ./run.sh.

This should put you into a singularity environment. To test if everything was succesful you can run:

cd ~/ur5_demo
python ur5_demo.py

And you should see an OpenRAVE window with UR5 being loaded.

Binding directories

As you can see from the above configuration you can have a home directory living on your host machine and then bind that directory as the home directory of the container. As a result you can now put files under that home dir and both the host and the container can read and write in it.

Another way to do this is to bind the directory using --bind (--bind=absolute_path_of_source_dir:absolute_path_of_target_dir) flag:

singularity run --contain --home=home:$HOME --bind=/home/rafael/Documents/my_project:/home/my_project ur5controller

This will bind /home/rafael/Documents/my_project to container's /home directory.

Unfortunetly, you can't bind the target directory to container's user home (e.g /home/rafael) directory. We found a workaround to this. Under home/.bashrc of this repository we have placed the following code:

# Delete all links that are broken
find ./ -maxdepth 1 -follow -type l -delete

# This code is to create a symbolic link of any directory located under /home/.
# When you use --bind in singularity to bind a directory from host to the container
# you can't bind that directory under $HOME but only under /home/, therefore a
# workaround to this was to create a symbolic link to all fo the directories under
# /home/ to $HOME.
for filename in $(find /home -maxdepth 1 ! -path "/home/$USER" ! -path '*/\.*' ! -path '/home'); do
    ln -sf $filename $HOME
done

This code will create symbolic links for every directory located under container's /home/ directory to $HOME (i.e., /home/user_name).

So with the above .bashrc code whenever you start a singularity container like this:

singularity run --contain --home=home:$HOME --bind=/home/rafael/Documents/my_project:/home/my_project ur5controller

Will bind /home/rafael/Documents/my_project to /home/my_project/ and will create a symbolic link of /home/my_project/ to /home/rafael/my_project. As a result we are "binding" a directory from the host file system to the container under container's user home directory.

With all that said, if you want to bind a directory to the container you just need to edit the run.sh file and add --bind=source:target as you wish.

For example:

singularity run --contain --home=home:$HOME --bind=/home/rafael/Documents/my_project_1:/home/my_project_1 --bind=/home/rafael/Documents/my_project_2:/home/my_project_2 ur5controller

Here we are binding two directories: my_project_1 and my_project_2.

Notes

• Note that we have pre-generated the robot inverse kinematics for OpenRAVE and placed them under your singularity home directory just to save time as this takes a while. This is just the kinematics for our specific configuration, if you change the model then OpenRAVE will generate new IK solutions for your new model.
• During build time we create some temporary files (scripts and build) that we are using to build everything. Once finished we erase those files.
• The home directory located under this repository contains the following important data: .openrave with the prepoulated IK solutions to UR5 robot, .bashrc containing important commands to successfully run ROS and the UR5Controller.
• Anything you create in the container under home will be persistent but if you write anything outside home this will not be writable. If you need to make changes to the singularity container, then run write.sh to enter into a root session within your singularity container.
• You can work in home directory outside singularity (say if you are using an IDE software) and the changes should be immediately available within the singularity environment. So you can edit your source code outside the container using your host machine and then execute the code within the container.