ubuntu16.04编译ORBSLAM2问题解决

• 在编译ubuntu16.04ros包的时候出现以下问题
• `/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:218: recipe for target ‘../RGBD’ failed
  make[2]: * [../RGBD] Error 1
  CMakeFiles/Makefile2:67: recipe for target ‘CMakeFiles/RGBD.dir/all’ failed
  make[1]: * [CMakeFiles/RGBD.dir/all] Error 2
  make[1]: * 正在等待未完成的任务….
  /usr/bin/ld: CMakeFiles/Stereo.dir/src/ros_stereo.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/Stereo.dir/build.make:218: recipe for target ‘../Stereo’ failed
  make[2]: * [../Stereo] Error 1
  CMakeFiles/Makefile2:104: recipe for target ‘CMakeFiles/Stereo.dir/all’ failed
  make[1]: * [CMakeFiles/Stereo.dir/all] Error 2
  Makefile:127: recipe for target ‘all’ failed
  make: * [all] Error 2

`
- 代码块高亮
- 出错原因为：libboost_system.so 与libboost_filesystem.so找不到链接目录
- 解决方案为

locate  boost_system
//查找到目录
/usr/lib/x86_64-linux-gnu/libboost_system.a
/usr/lib/x86_64-linux-gnu/libboost_system.so
/usr/lib/x86_64-linux-gnu/libboost_system.so.1.58.0
/usr/local/MATLAB/R2017a/bin/glnxa64/libboost_system.so.1.56.0

locate boost_filesystem
//查找到目录
/usr/lib/x86_64-linux-gnu/libboost_filesystem.a
/usr/lib/x86_64-linux-gnu/libboost_filesystem.so
/usr/lib/x86_64-linux-gnu/libboost_filesystem.so.1.58.0
/usr/local/MATLAB/R2017a/bin/glnxa64/libboost_filesystem.so.1.56.0

将libboost_system.so与libboost_filesystem.so复制到ORB_SLAM2/lib下，并且将ORBSLAM2/Examples/ROS/ORBSLAM2下的Cmakelists.txt中加入库目录，具体为
在set(LIBS
${OpenCV_LIBS}
${EIGEN3_LIBS}
${Pangolin_LIBRARIES}
${PROJECT_SOURCE_DIR}/../../../Thirdparty/DBoW2/lib/libDBoW2.so
${PROJECT_SOURCE_DIR}/../../../Thirdparty/g2o/lib/libg2o.so
${PROJECT_SOURCE_DIR}/../../../lib/libORB_SLAM2.so
之后加入${PROJECT_SOURCE_DIR}/../../../lib/libboost_filesystem.so
${PROJECT_SOURCE_DIR}/../../../lib/libboost_system.so
问题得以解决

[  0%] Built target rospack_genmsg_libexe
[  0%] Built target rosbuild_precompile
[ 11%] Linking CXX executable ../Mono
[ 22%] Linking CXX executable ../RGBD
[ 33%] Linking CXX executable ../Stereo
[ 44%] Linking CXX executable ../MonoAR
[ 55%] Built target Mono
[ 66%] Built target RGBD
[ 77%] Built target Stereo
[100%] Built target MonoAR