UBUNTU VERSIONS:

Locosim is compatible with Ubuntu 18/20. The installation instructions have been generalized accordingly. You need replace four strings (PYTHON_PREFIX, PYTHON_VERSION, PIP_PREFIX, ROS_VERSION) with the appropriate values according to your operating systems as follows:

Ubuntu 18:	Ubuntu 20:
PYTHON_PREFIX = python3	PYTHON_PREFIX = python3
PYTHON_VERSION = 3.5	PYTHON_VERSION = 3.8
ROBOTPKG_PYTHON_VERSION=py35	ROBOTPKG_PYTHON_VERSION=py38
PIP_PREFIX = pip3	PIP_PREFIX = pip3
ROS_VERSION = bionic	ROS_VERSION = noetic

NOTE: ROS is no longer supported (only ROS2 Humble) on Ubuntu 22 hence is not possible to install Locosim on Ubuntu 22.

Install ROS

setup your source list:

sudo sh -c 'echo "deb http://packages.ros.org/ros/ubuntu $(lsb_release -sc) main" > /etc/apt/sources.list.d/ros-latest.list'

Set up your keys:

curl -sSL 'http://keyserver.ubuntu.com/pks/lookup?op=get&search=0xC1CF6E31E6BADE8868B172B4F42ED6FBAB17C654' | sudo apt-key add -

install ROS main distro:

sudo apt-get install ros-ROS_VERSION-desktop-full

install ROS packages:

sudo apt-get install ros-ROS_VERSION-urdfdom-py

sudo apt-get install ros-ROS_VERSION-srdfdom

sudo apt-get install ros-ROS_VERSION-joint-state-publisher

sudo apt-get install ros-ROS_VERSION-joint-state-publisher-gui

sudo apt-get install ros-ROS_VERSION-joint-state-controller 

sudo apt-get install ros-ROS_VERSION-gazebo-msgs

sudo apt-get install ros-ROS_VERSION-control-toolbox

sudo apt-get install ros-ROS_VERSION-gazebo-ros

sudo apt-get install ros-ROS_VERSION-controller-manager

sudo apt install ros-ROS_VERSION-joint-trajectory-controller

Pinocchio stuff

Add robotpkg as source repository to apt:

sudo sh -c "echo 'deb [arch=amd64] http://robotpkg.openrobots.org/packages/debian/pub $(lsb_release -sc) robotpkg' >> /etc/apt/sources.list.d/robotpkg.list"

sudo sh -c "echo 'deb [arch=amd64] http://robotpkg.openrobots.org/wip/packages/debian/pub $(lsb_release -sc) robotpkg' >> /etc/apt/sources.list.d/robotpkg.list"

Register the authentication certificate of robotpkg:

sudo apt install -qqy lsb-release gnupg2 curl

curl http://robotpkg.openrobots.org/packages/debian/robotpkg.key | sudo apt-key add -

You need to run at least once apt update to fetch the package descriptions:

sudo apt-get update

Now you can install Pinocchio and the required libraries:

sudo apt install robotpkg-PINOCCHIO_PYTHON_VERSION-eigenpy	

sudo apt install robotpkg-PINOCCHIO_PYTHON_VERSION-pinocchio

sudo apt-get install robotpkg-PINOCCHIO_PYTHON_VERSION-quadprog  

NOTE: If you have issues in installing robotpkg libraries you can try to install them through ROS as:

sudo apt-get install ros-ROS_VERSION-LIBNAME

Python

sudo apt-get install PYTHON_PREFIX-scipy

sudo apt-get install PYTHON_PREFIX-matplotlib

sudo apt-get install PYTHON_PREFIX-termcolor

sudo apt install python3-pip

PIP_PREFIX install cvxpy==1.2.0

Support for Realsense camera (simulation)

This packages are needed if you want to see the PointCloud published by a realsense camera attached at the endeffector. To activate it, you should load the xacro of the ur5 with the flag "vision_sensor:=true".

sudo apt-get install ros-ROS_VERSION-openni2-launch

sudo apt-get install ros-ROS_VERSION-openni2-camera

sudo apt install ros-ROS_VERSION-realsense2-description

Support to simulate Grasping

Unfortunately grasping in Gazebo is still an open issue, I impelented grasping using this plugin that creates a fixed link between the gripper and the object to be grasped. To activate the grasping plugin set gripper_sim parameter to True in your configuration file. The following dependencies are required:

sudo apt-get install ros-ROS_VERSION-eigen-conversions 

sudo apt-get install ros-ROS_VERSION-object-recognition-msgs

sudo apt install ros-ROS_VERSION-roslint

You can check which parameters have to be tuned looking to the following wiki

Configure environment variables

gedit  ~/.bashrc

copy the following lines (at the end of the .bashrc), remember to replace the string PYTHON_VERSION with the appropriate version name as explained in software versions section:

source /opt/ros/ROS_VERSION/setup.bash
source $HOME/ros_ws/install/setup.bash
export PATH=/opt/openrobots/bin:$PATH
export LOCOSIM_DIR=$HOME/ros_ws/src/locosim
export PYTHONPATH=/opt/openrobots/lib/pythonPYTHON_VERSION/site-packages:$LOCOSIM_DIR/robot_control:$PYTHONPATH
export ROS_PACKAGE_PATH=$ROS_PACKAGE_PATH:/opt/openrobots/share/

the .bashrc is a file that is automatically sourced whenever you open a new terminal.

NOTE: people with some operating systems like ARCH LINUX, might need to add "export ROS_IP=127.0.0.1" to the .bashrc.

Download code and setup ROS workspace

Now that you installed all the dependencies you are ready to get the code, but first you need to create a ros workspace to out the code in:

mkdir -p ~/ros_ws/src

cd ~/ros_ws/src

Now you can clone the repository inside the ROS workspace you just created:

git clone https://github.com/mfocchi/locosim.git --recursive

this command should also clone all the submodules, if you want to update them separately just run

git submodule update --init --recursive

source the environment variables

source $HOME/.bashrc

now compile (then this step won't bee needed anymore if you just work in python unless you do not modify / create additional ROS packages)

cd ~/ros_ws/

catkin_make install

the install step install the ros packages inside the "$HOME/ros_ws/install" folder rather than the devel folder. This folder will be added to the ROS_PACKAGE_PATH instead of the devel one. Whenever you modify some of the ROS packages (e.g. the ones that contain the xacro fles inside the robot_description folder), you need to install them to be sure they are been updated in the ROS install folder.

Finally, run (you should do it any time you add a new ros package)

rospack profile

There are some additional utilities that I strongly suggest to install. You can find the list here.

IMPORTANT!

The first time you compile the code the install folder is not existing, therefore won't be added to the PYTHONPATH with the command source $HOME/ros_ws/install/setup.bash, and you won't be able to import the package ros_impedance_controller. Therefore, only once, after the first time that you compile, run again :

source $HOME/ros_ws/install/setup.bash

Now you are ready to run the code as explained here.

Installing Git and SSH key (optional)

To install Git you can open a terminal and run:

sudo apt install git

After that, you can check the version installed and configure the credentials with:

$ git --version
$ git config --global user.name <"name surnace">
$ git config --global user.email <"youremail@yourdomain.it">

After this, if you don't have an SSH key for your Github account, you need to create a new one to use the repositories:

• go to Settings/SSH and GPG Keys

• open a terminal and run these commands:

  $ ssh-keygen 
  $ cd ~/.ssh/
  $ cat id_rsa.pub
  

  Copy the content of your public SSH into the box at the link before and press "New SSH key". You can now clone the repositories with SSH without having to issue the password every time (I suggest to do not set any passphrase).

Tips and Tricks (optional)

1. Most of virtual machines including Virtualbox, do not have support for GPU. This means that if you run Gazebo Graphical User Interface (GUI) it can become very slow. A way to mitigate this is to avoid to start the Gazebo GUI and only start the gzserver process that will compute the dynamics, you will keep the visualization in Rviz. This is referred to planners that employ BaseController or BaseControllerFixed classes. In the Python code where you start the simulator you need to pass this additional argument as follows:

additional_args = 'gui:=false'
p.startSimulator(..., additional_args =additional_args)

2. Another annoying point is the default timeout to kill Gazebo that is by default very long. You can change it (e.g. to 0.1s) by setting the _TIMEOUT_SIGINT = 0.1 and _TIMEOUT_SIGTERM = 0.1:

sudo gedit /opt/ros/ROS_VERSION/lib/PYTHON_PREFIX/dist-packages/roslaunch/nodeprocess.py

this will cause ROS to send a kill signal much sooner.