1. Ubuntu换源（通过软件和更新换源更简单）

• 备份文件：sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak
• 修改文件：sudo vi /etc/apt/sources.list，内容参考：https://mirror.tuna.tsinghua.edu.cn/help/ubuntu/ 以Ubuntu 18.04 LTS为例：

# 默认注释了源码镜像以提高 apt update 速度，如有需要可自行取消注释
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse

# 预发布软件源，不建议启用
# deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse
# deb-src https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-proposed main restricted universe multiverse

2. 添加ROS软件源

   sudo sh -c '. /etc/lsb-release && echo "deb https://mirrors.tuna.tsinghua.edu.cn/ros/ubuntu/ $DISTRIB_CODENAME main" >> /etc/apt/sources.list.d/ros-latest.list'
   

3. 添加密钥

   sudo apt-key adv --keyserver 'hkp://keyserver.ubuntu.com:80' --recv-key C1CF6E31E6BADE8868B172B4F42ED6FBAB17C654
   

4. 更新软件源

   sudo apt update//相比于apt-get而言，apt是更新、更为推崇的命令，尽量用这个
   

5. 安装ROS

sudo apt install ros-melodic-desktop-full

6. 初始化rosdepc

sudo apt install python3-pip
sudo pip3 install rosdepc
sudo rosdepc init
rosdepc update

7. 添加环境变量

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

8. 安装rosinstall

   sudo apt install python-rosinstall python-rosinstall-generator python-wstool build-essential
   rosinstall也是ROS中的一个常用工具，可以下载和安装ROS中的功能包程序。
   

9. 验证

   roscore
   rosrun turtlesim turtlesim_node
   rosrun turtlesim turtle_teleop_key