$ sudo sh -c 'echo "deb http://packages.ros.org/ros/ubuntu $(lsb_release -sc) main" > /etc/apt/sources.list.d/ros-latest.list'
$ sudo apt install curl
$ curl -s https://raw.githubusercontent.com/ros/rosdistro/master/ros.asc | sudo apt-key add -
$ sudo apt update
$ sudo apt install ros-noetic-desktop-full
$ echo $SHELL
# shell이 bash일 때 아래 명령어 실행
$ echo "source /opt/ros/noetic/setup.bash" >> ~/.bashrc
$ source ~/.bashrc
$ sudo apt install python3-rosdep python3-rosinstall python3-rosinstall-generator python3-wstool build-essential
$ sudo rosdep init
$ rosdep update
$ roscore
$ mkdir -p ~/catkin_ws/src
$ cd catkin_ws
$ catkin_make
만약 Could NOT find PY_em (missing: PY_EM) error가 발생하면 아래 명령어 실행
$ pip install empy
$ vim ~/.bashrc
# 마지막 줄에 추가
# insert 누른 후
source ~/catkin_ws/devel/setup.bash
# esc 누른 후
# :wq
# enter
$ source ~/.bashrc