1、添加中科大ROS源
1.1、添加源
sudo sh -c '. /etc/lsb-release && echo "deb http://mirrors.ustc.edu.cn/ros/ubuntu/ `lsb_release -cs` main" > /etc/apt/sources.list.d/ros-latest.list'
1. 2、添加公钥
sudo apt-key adv --keyserver 'hkp://keyserver.ubuntu.com:80' --recv-key C1CF6E31E6BADE8868B172B4F42ED6FBAB17C654
1. 3、更新源
sudo apt update
2、安装ROS
2.1、版本选择
ROS分ROS1、ROS2，同时在不同ubuntu版本下有不同的版本。
ubuntu18.04对应的版本：
ROS1——Melodic Morenia
ROS2——Dashing Diademata
2.2、安装ROS1
sudo apt install ros-melodic-desktop-full
sudo apt install ros-melodic-rqt*
这个命令将安装完整的ROS软件，包括ROS，rqt，rviz，机器人通用库，2D / 3D模拟器，导航和2D / 3D感知等等的全套基础组件
2.3、设置环境变量
echo "source /opt/ros/melodic/setup.bash" >> ~/.bashrc
source ~/.bashrc
2.4、下载python-ros组件
sudo apt install python-rosdep python-rosinstall python-rosinstall-generator python-wstool build-essential
3、使用
3.1、初始化rosdep
初始化rosdep时报错：
$ sudo rosdep init
ERROR: cannot download default sources list from:
https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/sources.list.d/20-default.list
Website may be down.
解决方法参考：解决rosdep init ERROR: cannot download default sources list 问题
修改文件 /etc/hosts
203.208.40.66 translate.google.com
203.208.40.66 translate.googleapis.com
199.232.28.133 raw.githubusercontent.com
192.30.253.118 gist.github.com
185.199.110.153 github.io
151.101.113.194 github.global.ssl.fastly.net
52.216.227.168 github-cloud.s3.amazonaws.com
52.74.223.119 github.com
199.232.28.133 avatars1.githubusercontent.com
199.232.28.133 avatars2.githubusercontent.com
199.232.28.133 avatars0.githubusercontent.com
199.232.28.133 avatars3.githubusercontent.com
199.232.28.133 user-images.githubusercontent.com
199.232.28.133 avatars.githubusercontent.com
199.232.28.133 github.map.fastly.net
199.232.28.133 avatars7.githubusercontent.com
# Amazon AWS Start
54.239.31.69 aws.amazon.com
54.239.30.25 console.aws.amazon.com
54.239.96.90 ap-northeast-1.console.aws.amazon.com
54.240.226.81 ap-southeast-1.console.aws.amazon.com
54.240.193.125 ap-southeast-2.console.aws.amazon.com
54.239.54.102 eu-central-1.console.aws.amazon.com
177.72.244.194 sa-east-1.console.aws.amazon.com
176.32.114.59 eu-west-1.console.aws.amazon.com
54.239.31.128 us-west-1.console.aws.amazon.com
54.240.254.230 us-west-2.console.aws.amazon.com
54.239.38.102 s3-console-us-standard.console.aws.amazon.com
54.231.49.3 s3.amazonaws.com
52.219.0.4 s3-ap-northeast-1.amazonaws.com
54.231.242.170 s3-ap-southeast-1.amazonaws.com
54.231.251.21 s3-ap-southeast-2.amazonaws.com
54.231.193.37 s3-eu-central-1.amazonaws.com
52.218.16.140 s3-eu-west-1.amazonaws.com
52.92.72.2 s3-sa-east-1.amazonaws.com
54.231.236.6 s3-us-west-1.amazonaws.com
54.231.168.160 s3-us-west-2.amazonaws.com
52.216.80.48 github-cloud.s3.amazonaws.com
54.231.40.3 github-com.s3.amazonaws.com
52.216.20.171 github-production-release-asset-2e65be.s3.amazonaws.com
52.216.228.168 github-production-user-asset-6210df.s3.amazonaws.com
修改文件：/etc/resolv.conf ，添加google的DNS
nameserver 8.8.8.8
nameserver 8.8.4.4
注：系统中缺少文件 /etc/ros/rosdep/sources.list.d/20-default.list，内容如下
# os-specific listings first
yaml https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/osx-homebrew.yaml osx
# generic
yaml https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/base.yaml
yaml https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/python.yaml
yaml https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/ruby.yaml
gbpdistro https://raw.githubusercontent.com/ros/rosdistro/master/releases/fuerte.yaml fuerte
# newer distributions (Groovy, Hydro, ...) must not be listed anymore, they are being fetched from the rosdistro index.yaml instead
3.2、更新
rosdep update
注意：更新时，不要使用root权限，即不要使用sudo，否则会有提示
$ sudo rosdep update
reading in sources list data from /etc/ros/rosdep/sources.list.d
Warning: running 'rosdep update' as root is not recommended.
You should run 'sudo rosdep fix-permissions' and invoke 'rosdep update' again without sudo.
万一使用sudo，可以使用提示的命令清除下，然后再使用rosdep update
sudo rosdep fix-permissions
rosdep update
如果报错，多执行几遍
3.3、安装Catkin
Catkin是ROS对CMake进行的扩展
sudo apt-get install ros-melodic-catkin python-catkin-tools
4、运行
ROS著名的测试程序就是：键盘控制小乌龟运动；
分别在三个终端中运行，如下命令：
roscore
rosrun turtlesim turtlesim_node
rosrun turtlesim turtle_teleop_key
效果如下：
