Ubuntu 20.04 安装ROS Noetic

ros noetic将是ros1的最后一个版本

Configure your Ubuntu repositories to allow "restricted," "universe," and "multiverse."

1、设置软件源

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

2、添加秘钥

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

3、更新源列表并安装

sudo apt update

sudo apt install ros-noetic-desktop-full

4、设置环境变量

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

source ~/.bashrc

5、构建包的依赖项

初始ros noetic版本发布时，没有这一命令，后来补上了

sudo apt install python3-rosdep python3-rosinstall python3-rosinstall-generator python3-wstool build-essential
sudo rosdep init
rosdep update

如果你的网络穿墙能力不佳，执行rosdep init和rosdep update可能失败报错。解决办法如下

#安装rosdepc
pip3 install rosdepc

#执行rosdepc init会下载/etc/ros/rosdep/sources.list.d/20-default.list这个文件
rosdepc init

#打开/usr/lib/python3/dist-packages/rosdistro/__init__.py文件，修改DEFAULT_INDEX_URL
#修改为清华源即可
sudo vim /usr/lib/python3/dist-packages/rosdistro/__init__.py

DEFAULT_INDEX_URL = 'https://mirrors.tuna.tsinghua.edu.cn/rosdistro/index-v4.yaml'

#备注如果在Ubuntu18.04中，先修改
sudo vim /usr/lib/python2.7/dist-packages/rosdistro/__init__.py
#如果修改下面文件中的地址后,执行rosdep update后，打印的Query rosdistro index的地址仍是原来的地址，

#那就再修改
sudo vim /usr/local/lib/python3.6/dist-packages/rosdistro/__init__.py
#如果还不行，那就再修改
sudo vim ~/.local/lib/python2.7/site-packages/rosdistro/__init__.py