Ubuntu18.04下成功实现ORB_SLAM2 奥比中光astra深度相机
在ROS环境下，采用奥比中光的Astra深度相机，复现ORB_SLAM2代码，真的太难了，不过csdn上有好多大佬，纯纯地靠大佬们带飞，基本上我是参照这篇博客使用奥比中光Orbbec Astra Pro在ROS下跑orb_slam2_梁小憨憨的博客-CSDN博客来实现的，博主写的超级详细，简直是搞视觉SLAM小白的福音。所以针对我在实现ORB_SLAM2过程中存在的问题做个简单整理：
一、在ROS melodic环境下安装奥比中光相机驱动
1、按照参考的博客开始安装，到run astra_camera这步时，深度图可以看到，彩色图像显示“NO image”,应该是相机接口的问题，我试了他的解决方法，好像还是有问题，然后就去一顿搜索。
（1）首先查看相机接口：
lsusb可以查阅到：
Bus 001 Device 019: ID 2bc5:0502 # RGB模块
Bus 001 Device 018: ID 2bc5:0403 # 深度模块
（2）接着修改Astrapro.launch
cd ~/home/wsy/robot_positioning_ws/src/astra_camera/launch
gedit astrapro.launch改为如下所示：（只改RGB模块）
source一下：
source ~/rgbd_ws/devel/setup.bash再次运行：
roslaunch astra_camera astrapro.launch二、安装ORB_SLAM2
按照步骤一步步来，直到实时运行ORB_SLAM2在编译的时候出现问题了：
./build_ros.sh运行完之后会出现一堆错误，按照这篇Ubuntu18.04 编译 ORB-SLAM2（./build.sh + ./build_ros.sh）完整流程，各种报错处理（踩坑总结）_m0_60355964的博客-CSDN博客_./build_ros.sh
1、解决部分问题，但是有个“'sudo rosdep init' and 'rosdep update'”问题困扰很久：
[rosbuild] Building package ORB_SLAM2
Failed to invoke /opt/ros/noetic/bin/rospack deps-manifests ORB_SLAM2
[rospack] Error: the rosdep view is empty: call 'sudo rosdep init' and 'rosdep update'
CMake Error at /opt/ros/noetic/share/ros/core/rosbuild/public.cmake:129 (message):
Failed to invoke rospack to get compile flags for package 'ORB_SLAM2'.
Look above for errors from rospack itself. Aborting. Please fix the
broken dependency!Call Stack (most recent call first):
/opt/ros/noetic/share/ros/core/rosbuild/public.cmake:207 (rosbuild_invoke_rospack)
CMakeLists.txt:4 (rosbuild_init)
-- Configuring incomplete, errors occurred!
See also "/home/liuxinze/catkin_ws/src/ORB_SLAM2/Examples/ROS/ORB_SLAM2/build/CMakeFiles/CMakeOutput.log".
make: *** No targets specified and no makefile found. Stop.
按照如下步骤进行终端输入：
sudo -H pip3 install rosdepc
sudo rosdepc init
rosdepc update
参考：orb_slam2编译 ./build_ros.sh出现问题 很久没办法解决 请大家帮个忙谢谢！-编程语言-CSDN问答
2、还遇到了“Pangolin could not be found because dependency Eigen3 could not be found”的问题。
问题报错如下：
CMake Error at CMakeLists.txt:25 (find_package):
Found package configuration file:/usr/local/lib/cmake/Pangolin/PangolinConfig.cmake
but it set Pangolin_FOUND to FALSE so package "Pangolin" is considered to
be NOT FOUND. Reason given by package:Pangolin could not be found because dependency Eigen3 could not be found.
-- Configuring incomplete, errors occurred!
See also "/home/dongying/study/ManhattanSLAM/build/CMakeFiles/CMakeOutput.log".
See also "/home/dongying/study/ManhattanSLAM/build/CMakeFiles/CMakeError.log".
Makefile:940: recipe for target 'cmake_check_build_system' failed
make: *** [cmake_check_build_system] Error 1
参照博客：Pangolin could not be found because dependency Eigen3 could not be found._复古蓝的博客-CSDN博客
解决方法如下：
在CMakeLists.txt文件下修改，CMakeLists.txt文件路径为：
/home/wsy/工作空间/src/ORB_SLAM2/Examples/ROS/ORB_SLAM2
找到find_package(Eigen3 3.1.0 REQUIRED）并进行以下修改：
find_package(Eigen3 REQUIRED NO_MODULE)这样问题就解决的差不多了，可以正常运行了。