一、安装Intel® RealSense™ SDK 2.0

         Intel® RealSense™ SDK 2.0 的DKMS内核驱动包（librealsense2-dkms）支持Ubuntu LTS内核版本4.4、4.8、4.10、4.13、4.15、4.18、5.0、5.3、5.4。

        1.1 查看自己的内核版本：

sudo cat /proc/version

        如果非上述版本，需要手动安装和修补版本，请移步官网教程：https://github.com/IntelRealSense/librealsense/blob/master/doc/distribution_linux.md

本教程不适合你。

        1.2 注册服务器公钥：

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-key F6E65AC044F831AC80A06380C8B3A55A6F3EFCDE || sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-key F6E65AC044F831AC80A06380C8B3A55A6F3EFCDE

        如果公钥无法检索，检查并指定代理设置：

export http_proxy="http://<proxy>:<port>"

        重新运行该命令。

        1.3 将服务器添加到储存库列表

sudo add-apt-repository "deb https://librealsense.intel.com/Debian/apt-repo $(lsb_release -cs) main" -u

        1.4 安装库

sudo apt-get install librealsense2-dkms
sudo apt-get install librealsense2-utils

        上面两行代码将部署librealsense2 udevs规则，构建和激活内核模块、运行库和可执行演示和工具包。

        1.5 可选择安装开发人员和调试包：

sudo apt-get install librealsense2-dev
sudo apt-get install librealsense2-dbg

        1.6 验证内核是否已经更新：

modinfo uvcvideo | grep "version:"

         version后面出现realsense表示更新成功。

        1.7 启动realsense-viewer

        插入D455相机，可能需要USB3.0及以上接口。启动realsense-viewer：

realsense-viewer

        通过界面左侧的选项可以打开imu，双目和rgb相机模块，右上可切换2D、3D界面：

         成功！退出realsense-viewer界面。

二、realsense-ros的安装与编译

        2.1 创建工作空间

       创建工作空间 ，这里~/Packages/RealsenseRos_ws可以自定义路径，但必须包含/src：

mkdir -p ~/Packages/RealsenseRos_ws/src

cd ~/Packages/RealsenseRos_ws/src

         2.2 从github上下载realsense-ros并修改指针：

git clone https://github.com/IntelRealSense/realsense-ros.git
cd realsense-ros/
git checkout `git tag | sort -V | grep -P "^2.\d+\.\d+" | tail -1`
cd ..

        2.3 安装ddynamic_reconfigure

        初始化工作空间前，最好检查一下ddynamic_reconfigure是否安装。

        执行如下命令（注意将melodic改为自己的ROS对应版本，修改“melodic”为"kinect"、"neotic"等等）：

sudo apt-get install ros-melodic-ddynamic-reconfigure

        否则会出现报错：提示没有ddynamic_reconfigure。

        2.4 初始化工作空间       

catkin_init_workspace
cd ..
catkin_make clean

        2.5 安装源码

catkin_make -DCATKIN_ENABLE_TESTING=False -DCMAKE_BUILD_TYPE=Release
catkin_make install

        2.6 添加工作路径到bashrc文件

        注意修改~/Packages/RealsenseRos_ws/为自己的路径。

echo "source ~/Packages/RealsenseRos_ws/devel/setup.bash" >> ~/.bashrc
source ~/.bashrc

        2.7 插上相机并启动相机

        插上相机运行

roslaunch realsense2_camera rs_camera.launch

        如果出现报错：[camera/realsense2_camera_manager-2]进程已经死亡。报错如下：

/opt/ros/melodic/lib/nodelet/nodelet: symbol lookup error: /home/khz/ROS/catkin_ws/devel/lib//librealsense2_camera.so: undefined symbol: _ZN2cv3MatC1EiiiRKNS_7Scalar_IdEE
[camera/realsense2_camera_manager-2] process has died [pid 4924, exit code 127, cmd /opt/ros/melodic/lib/nodelet/nodelet manager __name:=realsense2_camera_manager __log:=/home/khz/.ros/log/81b1e24a-8f95-11ec-8270-344b50000000/camera-realsense2_camera_manager-2.log].
log file: /home/khz/.ros/log/81b1e24a-8f95-11ec-8270-344b50000000/camera-realsense2_camera_manager-2*.log
[camera/realsense2_camera-3] process has finished cleanly
log file: /home/khz/.ros/log/81b1e24a-8f95-11ec-8270-344b50000000/camera-realsense2_camera-3*.log

        如下图：

         由于出现提示：未定义标识符undefined symbol: _ZN2cv3MatC1EiiiRKNS_7Scalar_IdEE。猜测是OpenCV库的问题。

        解决方案：

        首先看看自己有没有安装OpenCV，没有安装请先安装，安装过程略。

        如果已经安装，打开realsense-ros的功能包文件夹下 realsense2_camera 文件夹下的 CmakeLists.txt文件，做出如下修改：

        添加set(OpenCV_DIR /usr/local/share/OpenCV/)到find_package前（下图11行，注意检查自己OpenCV的路径），添加OpenCV REQUIRED到find_package里（下图26行，注意放在括号里）。

         添加${OpenCV_LIBS}到目标链接库里（下图127行）

         然后跳回2.5再次安装，完成后执行roslaunch realsense2_camera rs_camera.launch。看到如下图就是启动成功了（有Realsense Node Is Up就行，警告可以忽略）。

         2.8 启动RGBD相机

        如果是RGBD相机，需启用第二步验证：

roslaunch realsense2_camera rs_rgbd.launch

        如果出现报错：

Resource not found: rgbd_launch
ROS path [0]=/opt/ros/melodic/share/ros
ROS path [1]=/home/andyvictory/Packages/RealsenseRos_ws/src
ROS path [2]=/opt/ros/melodic/share
The traceback for the exception was written to the log file

        安装RGBD的launch（注意ROS版本）：

sudo apt install ros-melodic-rgbd-launch

        安装成功！

参考文章：

https://blog.csdn.net/qq_44305475/article/details/123686786?ops_request_misc=&request_id=&biz_id=102&utm_term=d455&utm_medium=distribute.pc_search_result.none-task-blog-2~all~sobaiduweb~default-2-123686786.nonecase&spm=1018.2226.3001.4187https://blog.csdn.net/qq_44305475/article/details/123686786?ops_request_misc=&request_id=&biz_id=102&utm_term=d455&utm_medium=distribute.pc_search_result.none-task-blog-2~all~sobaiduweb~default-2-123686786.nonecase&spm=1018.2226.3001.4187https://blog.csdn.net/robinvista/article/details/115732239?ops_request_misc=&request_id=&biz_id=102&utm_term=d455&utm_medium=distribute.pc_search_result.none-task-blog-2~all~sobaiduweb~default-3-115732239.nonecase&spm=1018.2226.3001.4187https://blog.csdn.net/robinvista/article/details/115732239?ops_request_misc=&request_id=&biz_id=102&utm_term=d455&utm_medium=distribute.pc_search_result.none-task-blog-2~all~sobaiduweb~default-3-115732239.nonecase&spm=1018.2226.3001.4187

https://blog.csdn.net/qq_40186909/article/details/113104595?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522166312286216782391821994%2522%252C%2522scm%2522%253A%252220140713.130102334.pc%255Fall.%2522%257D&request_id=166312286216782391821994&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2~all~first_rank_ecpm_v1~pc_rank_v39-2-113104595-null-null.142%5Ev47%5Epc_rank_34_2,201%5Ev3%5Econtrol_2&utm_term=realsense%20%E7%9A%84%20D%20%E7%9F%A9%E9%98%B5&spm=1018.2226.3001.4187https://blog.csdn.net/qq_40186909/article/details/113104595?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522166312286216782391821994%2522%252C%2522scm%2522%253A%252220140713.130102334.pc%255Fall.%2522%257D&request_id=166312286216782391821994&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2~all~first_rank_ecpm_v1~pc_rank_v39-2-113104595-null-null.142%5Ev47%5Epc_rank_34_2,201%5Ev3%5Econtrol_2&utm_term=realsense%20%E7%9A%84%20D%20%E7%9F%A9%E9%98%B5&spm=1018.2226.3001.4187