1、安装UTF8，本操作会把当前系统的语言改为英文
sudo locale-gen en_US en_US.UTF-8
sudo update-locale LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8
export LANG=en_US.UTF-8
2、查看语言环境：locale
3、安装源设定
1）添加密钥
sudo apt update && sudo apt install curl gnupg2 lsb-release
curl -s https://raw.githubusercontent.com/ros/rosdistro/master/ros.asc | sudo apt-key add -
2）安装源添加
sudo sh -c 'echo "deb [arch=amd64,arm64] http://packages.ros.org/ros2/ubuntu `lsb_release -cs` main" > /etc/apt/sources.list.d/ros2-latest.list'
4、安装ros2
sudo apt update
sudo apt install ros-eloquent-desktop
（或者使用基础版：sudo apt install ros-eloquent-ros-base）
5、环境配置
1)? echo "source /opt/ros/eloquent/setup.bash" >> ~/.bashrc
2) 有可能再/opt/ros/eloquent/中没有setup.bash，如下：
bin ?cmake ?include ?lib ?local_setup.bash ?local_setup.sh ?_local_setup_util.py ?local_setup.zsh ?opt ?setup.bash ?setup.sh ?setup.zsh ?share ?src
那么可以：source local_setup.bash
3)在安装了melodic ros的系统会报错
ROS_DISTRO was set to 'melodic' before. Please make sure that the environment does not mix paths from different distributions.
6、ros2命令的自动补全
sudo apt install python3-argcomplete
7、通信测试
开一个终端：ros2 run demo_nodes_cpp talker
再开一个终端：ros2 run demo_nodes_py listener
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