# ROS

## ROS
### Install [ROS Melodic Morenia](http://wiki.ros.org/melodic/Installation/Ubuntu) in Ubuntu 18.04 LTS (Bionic Beaver)

# setup your sources.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 -s https://raw.githubusercontent.com/ros/rosdistro/master/ros.asc | sudo apt-key add -

# installation
sudo apt update
sudo apt install ros-melodic-desktop-full

# environment setup for bash
echo "source /opt/ros/melodic/setup.bash" >> ~/.bashrc
source ~/.bashrc

# environment setup for zsh
echo "source /opt/ros/melodic/setup.zsh" >> ~/.zshrc
source ~/.zshrc

# dependencies for building packages
sudo apt install python-rosdep python-rosinstall python-rosinstall-generator python-wstool build-essential

# initialize rosdep
sudo rosdep init
rosdep update

### Command Cheat Sheet
-`rqt_graph`

---

## ROS 2
### Install ROS 2 Galactic Geochelone
- Offical [building guide](https://docs.ros.org/en/galactic/Installation/Ubuntu-Development-Setup.html#building-ros-2-on-ubuntu-linux) is for Ubuntu 20.04
- The following building step is tested on Ubuntu 18.04

#### Building ROS 2 on Ubuntu 18.04

# Add the ROS 2 apt repository
sudo apt install software-properties-common
sudo add-apt-repository universe
sudo apt update && sudo apt install curl gnupg lsb-release
sudo curl -sSL https://raw.githubusercontent.com/ros/rosdistro/master/ros.key  -o /usr/share/keyrings/ros-archive-keyring.gpg
echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/ros-archive-keyring.gpg] http://packages.ros.org/ros2/ubuntu $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/ros2.list > /dev/null

# Install development tools and ROS tools
sudo apt update && sudo apt install -y \
  build-essential \
  cmake \
  git \
  python3-colcon-common-extensions \
  python3-flake8 \
  python3-pip \
  python3-pytest-cov \
  python3-rosdep \
  python3-setuptools \
  python3-vcstool \
  wget
# install some pip packages needed for testing
python3 -m pip install -U \
  flake8-blind-except \
  flake8-builtins \
  flake8-class-newline \
  flake8-comprehensions \
  flake8-deprecated \
  flake8-docstrings \
  flake8-import-order \
  flake8-quotes \
  pytest-repeat \
  pytest-rerunfailures \
  pytest \
  setuptools

# Install dependencies fot Ubuntu 18.04
python3 -m pip install -U importlib-metadata importlib-resources

# Get ROS 2 code
mkdir -p ~/ros2_galactic/src
cd ~/ros2_galactic
wget https://raw.githubusercontent.com/ros2/ros2/galactic/ros2.repos
vcs import src < ros2.repos

# Install dependencies using rosdep
sudo rosdep init
rosdep update
rosdep install --from-paths src --ignore-src --rosdistro galactic -y --skip-keys "console_bridge fastcdr fastrtps rti-connext-dds-5.3.1 urdfdom_headers"

# Build the code in the workspace
cd ~/ros2_galactic/
colcon build --symlink-install

##### Environment setup

# Source the setup script
. ~/ros2_galactic/install/local_setup.bash

##### Examples

# In one terminal
. ~/ros2_galactic/install/local_setup.bash
ros2 run demo_nodes_cpp talker

# In another terminal
. ~/ros2_galactic/install/local_setup.bash
ros2 run demo_nodes_py listener

### Command Cheat Sheet
- `ros2 topic info /turtle1/cmd_vel`
- `ros2 topic echo /scan`
- `ros2 service list -t`
- `ros2 node list`
- `colcon build --packages-select flip_laser`
- `ros2 param list`

### RCLPY
#### Logging
- https://github.com/ros2/examples/blob/669ec3e6807a0b2620a01b26513e713e8a9a14f0/rclpy/services/minimal_client/examples_rclpy_minimal_client/client.py#L35

---

## Gazebo
- Run Gazebo in VMware
`export SVGA_VGPU10=0`
`echo "export SVGA_VGPU10=0" >> ~/.bashrc`
https://answers.gazebosim.org//question/13214/virtual-machine-not-launching-gazebo/
- [Aerodynamics](http://gazebosim.org/tutorials?tut=aerodynamics&cat=physics)

## Reference
- https://varhowto.com/install-ros-noetic-raspberry-pi-4/