ROS2-Foxy安装流程

一、安装流程

安装环境：Ubuntu 20.04 + VMWare 16.0 Pro
ROS版本：ROS2 Foxy

1. 设置编码

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.设置软件源

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 -
 
sudo sh -c 'echo "deb [arch=$(dpkg --print-architecture)] http://packages.ros.org/ros2/ubuntu $(lsb_release -cs) main" > /etc/apt/sources.list.d/ros2-latest.list'

3.安装ROS2

sudo apt update
sudo apt install ros-foxy-desktop

4.设置环境变量

source /opt/ros/foxy/setup.bash

如果有安装ROS1，会提示一个警告

5.安装自动补全工具

sudo apt install python3-argcomplete

跑几个例程测试一下： 先运行一个talker：

source /opt/ros/foxy/setup.bash
ros2 run demo_nodes_cpp talker

再运行一个Listener

source /opt/ros/foxy/setup.bash
ros2 run demo_nodes_py listener

ROS2的RWM默认使用的DDS是Fast RTPS，Cyclone DDS默认也安装好了，还可以这样安装RTI Connext：

sudo apt update
sudo apt install ros-foxy-rmw-connext-cpp

安装之后通过环境变量即可切换DDS：

RMW_IMPLEMENTATION=rmw_connext_cpp

如果哪一天不喜欢了，还可以这样删除：

sudo apt remove ros-foxy-* && sudo apt autoremove

二、配置环境变量

workspace是ROS2中的工作空间，也是我们开发机器人代码的位置。 ROS2安装的系统目录称之为“underlay”，我们自己创建的工作空间称之为“overlay”，在一台电脑上往往有多个工作空间。我们可以通过source不同空间的环境变量脚本来更换所使用的workspace，包括ROS2的版本。 如果使用的是Linux系统或者MacOS，需要先熟悉Linux命令行的基本操作，可以参考该教程：http://www.ee.surrey.ac.uk/Teaching/Unix/

设置环境变量

source /opt/ros/foxy/setup.bash

这种方法只能在运行该指令的终端中有效，如果需要在每一个终端中都生效的话，需要将脚本放到bash的启动脚本中：

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

设置完成后查看一下你的环境变量是否设置成功：

printenv | grep -i ROS

如果在局域网的多台电脑中使用ROS2，默认的通信机制会自动建立各机器分布式通信框架，也就是不同电脑之间已经可以通信了，如果你不希望多台电脑之间产生连接，可以设置不同的组网ID，相同ID的电脑之间可以通信，不同ID的电脑之间无法通信。

export ROS_DOMAIN_ID=<your_domain_id>
echo "export ROS_DOMAIN_ID=" >> ~/.bashrc

环境变量的设置在ROS2中非常重要，如果后续使用中发现某些找不到命令、找不到包、找不到文件的错误，都应该首先确认环境变量是否正确设置。

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ROS2 galactic installation

Building ROS 2 on Ubuntu Linux

Table of Contents

System requirements

System setup

    Set locale

    Add the ROS 2 apt repository

    Install development tools and ROS tools

Get ROS 2 code

Install dependencies using rosdep

Install additional DDS implementations (optional)

Build the code in the workspace

Environment setup

    Source the setup script

Try some examples

Next steps after installing

Using the ROS 1 bridge

Additional RMW implementations (optional)

Alternate compilers

    Clang

Stay up to date

Troubleshooting

Uninstall

System requirements

The current Debian-based target platforms for Galactic Geochelone are:

Tier 1: Ubuntu Linux - Focal Fossa (20.04) 64-bit

Tier 3: Debian Linux - Bullseye (11) 64-bit

Other Linux platforms with varying support levels include:

Arch Linux, see alternate instructions

Fedora Linux, see alternate instructions

OpenEmbedded / webOS OSE, see alternate instructions

As defined in REP 2000.
System setup
Set locale

Make sure you have a locale which supports UTF-8. If you are in a minimal environment (such as a docker container), the locale may be something minimal like POSIX. We test with the following settings. However, it should be fine if you’re using a different UTF-8 supported locale.

locale # check for UTF-8

sudo apt update && sudo apt install locales
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

locale # verify settings

Add the ROS 2 apt repository

You will need to add the ROS 2 apt repository to your system. First, make sure that the Ubuntu Universe repository is enabled by checking the output of this command.

apt-cache policy | grep universe
500 http://us.archive.ubuntu.com/ubuntu focal/universe amd64 Packages
release v=20.04,o=Ubuntu,a=focal,n=focal,l=Ubuntu,c=universe,b=amd64

If you don’t see an output line like the one above, then enable the Universe repository with these instructions.

sudo apt install software-properties-common
sudo add-apt-repository universe

Now add the ROS 2 apt repository to your system. First authorize our GPG key with apt.

sudo apt update && sudo apt install curl gnupg lsb-release
sudo curl -sSL https://raw.githubusercontent.com/ros/rosdistro/master/ros.key -o /usr/share/keyrings/ros-archive-keyring.gpg

Then add the repository to your sources list.

echo “deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/ros-archive-keyring.gpg] http://packages.ros.org/ros2/ubuntu $(source /etc/os-release && echo $UBUNTU_CODENAME) main” | sudo tee /etc/apt/sources.list.d/ros2.list > /dev/null

Install development tools and ROS tools

sudo apt update && sudo apt install -y
build-essential
cmake
git
python3-colcon-common-extensions
python3-flake8
python3-pip
python3-pytest-cov
python3-rosdep
python3-setuptools
python3-vcstool
wget

install some pip packages needed for testing

python3 -m pip install -U
flake8-blind-except
flake8-builtins
flake8-class-newline
flake8-comprehensions
flake8-deprecated
flake8-docstrings
flake8-import-order
flake8-quotes
pytest-repeat
pytest-rerunfailures
pytest
setuptools

Ubuntu 18.04 is not an officially supported platform, but may still work. You’ll need at least the following additional dependencies:

python3 -m pip install -U importlib-metadata importlib-resources

Get ROS 2 code

Create a workspace and clone all repos:

mkdir -p ~/ros2_galactic/src
cd ~/ros2_galactic
wget https://raw.githubusercontent.com/ros2/ros2/galactic/ros2.repos
vcs import src < ros2.repos

Install dependencies using rosdep

sudo rosdep init
rosdep update
rosdep install --from-paths src --ignore-src -y --skip-keys “fastcdr rti-connext-dds-5.3.1 urdfdom_headers”

Note: If you’re using a distribution that is based on Ubuntu (like Linux Mint) but does not identify itself as such, you’ll get an error message like Unsupported OS [mint]. In this case append --os=ubuntu:focal to the above command.
Install additional DDS implementations (optional)

If you would like to use another DDS or RTPS vendor besides the default, Eclipse Cyclone DDS, you can find instructions here.
Build the code in the workspace

If you have already installed ROS 2 another way (either via Debians or the binary distribution), make sure that you run the below commands in a fresh environment that does not have those other installations sourced. Also ensure that you do not have source /opt/ros/${ROS_DISTRO}/setup.bash in your .bashrc. You can make sure that ROS 2 is not sourced with the command printenv | grep -i ROS. The output should be empty.

More info on working with a ROS workspace can be found in this tutorial.

cd ~/ros2_galactic/
colcon build --symlink-install

Note: if you are having trouble compiling all examples and this is preventing you from completing a successful build, you can use COLCON_IGNORE in the same manner as CATKIN_IGNORE to ignore the subtree or remove the folder from the workspace. Take for instance: you would like to avoid installing the large OpenCV library. Well then simply run touch COLCON_IGNORE in the cam2image demo directory to leave it out of the build process.
Environment setup
Source the setup script

Set up your environment by sourcing the following file.

. ~/ros2_galactic/install/local_setup.bash

Try some examples

In one terminal, source the setup file and then run a C++ talker:

. ~/ros2_galactic/install/local_setup.bash
ros2 run demo_nodes_cpp talker

In another terminal source the setup file and then run a Python listener:

. ~/ros2_galactic/install/local_setup.bash
ros2 run demo_nodes_py listener

You should see the talker saying that it’s Publishing messages and the listener saying I heard those messages. This verifies both the C++ and Python APIs are working properly. Hooray!
Next steps after installing

Continue with the tutorials and demos to configure your environment, create your own workspace and packages, and learn ROS 2 core concepts.
Using the ROS 1 bridge

The ROS 1 bridge can connect topics from ROS 1 to ROS 2 and vice-versa. See the dedicated documentation on how to build and use the ROS 1 bridge.
Additional RMW implementations (optional)

The default middleware that ROS 2 uses is Cyclone DDS, but the middleware (RMW) can be replaced at runtime. See the guide on how to work with multiple RMWs.
Alternate compilers

Using a different compiler besides gcc to compile ROS 2 is easy. If you set the environment variables CC and CXX to executables for a working C and C++ compiler, respectively, and retrigger CMake configuration (by using --force-cmake-config or by deleting the packages you want to be affected), CMake will reconfigure and use the different compiler.
Clang

To configure CMake to detect and use Clang:

sudo apt install clang
export CC=clang
export CXX=clang++
colcon build --cmake-force-configure

Stay up to date

See Maintaining a source checkout of ROS 2 Galactic to periodically refresh your source installation.
Troubleshooting

Troubleshooting techniques can be found here.
Uninstall

If you installed your workspace with colcon as instructed above, “uninstalling” could be just a matter of opening a new terminal and not sourcing the workspace’s setup file. This way, your environment will behave as though there is no Galactic install on your system.

If you’re also trying to free up space, you can delete the entire workspace directory with:

rm -rf ~/ros2_galactic