使用奥比中光RGBD摄像头运行ORB_SLAM2

•  源码地址

　　https://github.com/raulmur/ORB_SLAM2.git

• 启动指令

　　第一个终端启动AstraPro Camera:

　　roslaunch astra_camera astrapro.launch

　　第二个终端启动ROS_SLAM：

　　rosrun ORB_SLAM2 RGBD xr_ws/src/ORB_SLAM2/Vocabulary/ORBvoc.txt xr_ws/src/ORB_SLAM2/Examples/ROS/ORB_SLAM2/AstraPro.yaml 

　　1.第一个参数指定相机类型：RGBD。根据实际需求另有Mono，MonoAR，Stereo，RGBD可选。

　　2.PATH_TO_VOCABULARY，指定ORBvoc.txt路径。

　　3.PATH_TO_SETTINGS_FILE，相机参数与ORB参数文件路径。

　　下面给出文中使用的配置文件，仅供参考。

%YAML:1.0
#--------------------------------------------------------------------------------------------
# Camera Parameters. Adjust them!
#--------------------------------------------------------------------------------------------
# Camera calibration and distortion parameters (OpenCV) 
Camera.fx: 564.2
Camera.fy: 563.7
Camera.cx: 328.6
Camera.cy: 236.4


Camera.k1: 0.138
Camera.k2: -0.185
Camera.p1: -0.0004
Camera.p2: 0.007
Camera.width: 640
Camera.height: 480
# Camera frames per second 
Camera.fps: 30.0
# IR projector baseline times fx (aprox.)
Camera.bf: 40.0
# Color order of the images (0: BGR, 1: RGB. It is ignored if images are grayscale)
Camera.RGB: 1
# Close/Far threshold. Baseline times.
ThDepth: 40.0
# Deptmap values factor
DepthMapFactor: 1.0
#--------------------------------------------------------------------------------------------
# ORB Parameters
#--------------------------------------------------------------------------------------------
# ORB Extractor: Number of features per image
ORBextractor.nFeatures: 1000
# ORB Extractor: Scale factor between levels in the scale pyramid     
ORBextractor.scaleFactor: 1.2
# ORB Extractor: Number of levels in the scale pyramid    
ORBextractor.nLevels: 8
# ORB Extractor: Fast threshold
# Image is divided in a grid. At each cell FAST are extracted imposing a minimum response.
# Firstly we impose iniThFAST. If no corners are detected we impose a lower value minThFAST
# You can lower these values if your images have low contrast            
ORBextractor.iniThFAST: 20
ORBextractor.minThFAST: 7
#--------------------------------------------------------------------------------------------
# Viewer Parameters
#--------------------------------------------------------------------------------------------
Viewer.KeyFrameSize: 0.05
Viewer.KeyFrameLineWidth: 1
Viewer.GraphLineWidth: 0.9
Viewer.PointSize:2
Viewer.CameraSize: 0.08
Viewer.CameraLineWidth: 3
Viewer.ViewpointX: 0
Viewer.ViewpointY: -0.7
Viewer.ViewpointZ: -1.8
Viewer.ViewpointF: 500

 

• 运行结果

　　(1) 特征点提取结果。

　　（2）点云图、相机位姿、追踪结果显示。

　　

• 问题记录

　  执行build_ros.sh 出现 'undefined reference to symbol '_ZN5boost6system15system_categoryEv' 错误，具体如下：

CMakeFiles/Makefile2:163: recipe for target 'CMakeFiles/Stereo.dir/all' failed
make[1]: *** [CMakeFiles/Stereo.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....
[100%] Linking CXX executable ../RGBD
/usr/bin/ld: CMakeFiles/RGBD.dir/src/ros_rgbd.cc.o: undefined reference to symbol '_ZN5boost6system15system_categoryEv'
/usr/lib/x86_64-linux-gnu/libboost_system.so: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
CMakeFiles/RGBD.dir/build.make:223: recipe for target '../RGBD' failed
make[2]: *** [../RGBD] Error 1
CMakeFiles/Makefile2:754: recipe for target 'CMakeFiles/RGBD.dir/all' failed
make[1]: *** [CMakeFiles/RGBD.dir/all] Error 2
Makefile:127: recipe for target 'all' failed
make: *** [all] Error 2

　　解决方法：切换目录至 Examples/ROS/ORB_SLAM2，编辑CMakeLists.txt,添加-lboost_system一项，如下所示。

set(LIBS 
${OpenCV_LIBS} 
${EIGEN3_LIBS}
${Pangolin_LIBRARIES}
${PROJECT_SOURCE_DIR}/../../../Thirdparty/DBoW2/lib/libDBoW2.so
${PROJECT_SOURCE_DIR}/../../../Thirdparty/g2o/lib/libg2o.so
${PROJECT_SOURCE_DIR}/../../../lib/libORB_SLAM2.so
-lboost_system
)

　　再次编译，错误消失。

• 参考文献

　　Mur-Artal R , Tardos J D . ORB-SLAM2: an Open-Source SLAM System for Monocular, Stereo and RGB-D Cameras[J]. IEEE Transactions on Robotics, 2017, 33(5):1255-1262.