SLAM-application: installation and test

• (3D): LeGO-LOAM, LIO-SAM, LVI-SAM, FAST-LIO2, Faster-LIO, VoxelMap, and R3LIVE
  • Tested on Quadruped robot in Gazebo
  • Tested with real-world data in E3-2 building of KAIST

● Results:

● video: Lego-LOAM vs LIO-SAM vs LVI-SAM

● video2: LIO-SAM vs LVI-SAM

● video3: LIO-SAM vs FAST-LIO2

● video4: FAST-LIO2 vs Livox-mapping vs LOAM-Livox using Livox Mid-70 LiDAR, real-world

● video5: FAST-LIO2 in the building with narrow stairs using Ouster OS0-128, real-world

● video6: FAST-LIO2 in the narrow tunnels using Ouster OS0-128 on the UAV (drone)

● video7: Faster-LIO vs FAST-LIO in the building with narrow stairs using Ouster OS0-128, real-world

● video8: VoxelMap in the building using Intel Realsense L515, real-world

● video9: R3LIVE in the building and around the building using Livox Mid-70 LiDAR, FLIR Blackfly S, Pixhawk4 mini, real-world

Requirements

• Dependencies

$ sudo apt-get install -y ros-melodic-navigation ros-melodic-robot-localization ros-melodic-robot-state-publisher

• GTSAM for LVI-SAM and LIO-SAM

$ wget -O gtsam.zip https://github.com/borglab/gtsam/archive/4.0.2.zip
$ unzip gtsam.zip
$ cd gtsam-4.0.2/
$ mkdir build && cd build
$ cmake -DGTSAM_BUILD_WITH_MARCH_NATIVE=OFF ..
$ sudo make install -j8

• Ceres solver only for LVI-SAM

$ sudo apt-get install -y cmake libgoogle-glog-dev libatlas-base-dev libsuitesparse-dev
$ wget http://ceres-solver.org/ceres-solver-1.14.0.tar.gz
$ tar zxf ceres-solver-1.14.0.tar.gz
$ mkdir ceres-bin
$ mkdir solver && cd ceres-bin
$ cmake ../ceres-solver-1.14.0 -DEXPORT_BUILD_DIR=ON -DCMAKE_INSTALL_PREFIX="../solver"  #good for build without being root privileged and at wanted directory
$ make -j8 # 8 : number of cores
$ make test
$ make install

• glog, g++-9 and gcc-9 for Faster-LIO

$ sudo apt-get install libgoogle-glog-dev
$ sudo add-apt-repository ppa:ubuntu-toolchain-r/test
$ sudo apt update
$ sudo apt install gcc-9 g++-9
$ sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-9 60 --slave /usr/bin/g++ g++ /usr/bin/g++-9

Note: Ouster-ros package cannot be built with gcc and g++ with the version higher than 6

• When building ouster-ros,

catkin b -DCMAKE_C_COMPILER=gcc-6 -DCMAKE_CXX_COMPILER=g++-6 -DCMAKE_BUILD_TYPE=Release

• CGAL and pcl-tools for R3LIVE

$ sudo apt install libcgal-dev pcl-tools

Optionally,
$ sudo apt install meshlab

Installation

● LeGO-LOAM

$ cd ~/your_workspace/src
$ git clone https://github.com/RobustFieldAutonomyLab/LeGO-LOAM.git
$ cd ..
$ catkin build -DCMAKE_BUILD_TYPE=Release

● LIO-SAM

$ cd ~/your_workspace/src
$ git clone https://github.com/TixiaoShan/LIO-SAM.git
$ cd ..
$ catkin build -DCMAKE_BUILD_TYPE=Release

● LVI-SAM

$ cd ~/your_workspace/src
$ git clone https://github.com/TixiaoShan/LVI-SAM.git
$ cd ..
$ catkin build -DCMAKE_BUILD_TYPE=Release

● Trouble shooting for LVI-SAM

• for OpenCV 4.X, edit LVI-SAM/src/visual_odometry/visual_loop/ThirdParty/DVision/BRIEF.cpp:53

// cv::cvtColor(image, aux, CV_RGB2GRAY);
cv::cvtColor(image, aux, cv::COLOR_RGB2GRAY);

● FAST-LIO2

$ cd ~/your_workspace/src
$ git clone https://github.com/Livox-SDK/livox_ros_driver.git
$ cd ..
$ catkin build -DCMAKE_BUILD_TYPE=Release

$ cd ~/your_workspace/src
$ git clone --recursive https://github.com/hku-mars/FAST_LIO.git
$ cd ..
$ catkin build -DCMAKE_BUILD_TYPE=Release

● Faster-LIO

$ cd ~/your_workspace/src
$ git clone https://github.com/gaoxiang12/faster-lio.git

$ cd faster-lio/thirdparty
$ tar -xvf tbb2018_20170726oss_lin.tgz

$ cd ~/your_workspace
$ catkin build -DCUSTOM_TBB_DIR=$(pwd)/src/faster-lio/thirdparty/tbb2018_20170726oss -DCMAKE_BUILD_TYPE=Release

● VoxelMap

$ cd ~/your_workspace/src
$ git clone https://github.com/Livox-SDK/livox_ros_driver.git
$ cd ..
$ catkin build -DCMAKE_BUILD_TYPE=Release

$ git clone https://github.com/hku-mars/VoxelMap.git
$ cd ..
$ catkin build -DCMAKE_BUILD_TYPE=Release

● Trouble shooting for VoxelMap

• /usr/include/lz4.h:196:57: error: conflicting declaration ‘typedef struct LZ4_stream_t LZ4_stream_t’ ...
  • You could meet this error in ROS-melodic. Fix as here

$ sudo mv /usr/include/flann/ext/lz4.h /usr/include/flann/ext/lz4.h.bak
$ sudo mv /usr/include/flann/ext/lz4hc.h /usr/include/flann/ext/lz4.h.bak

$ sudo ln -s /usr/include/lz4.h /usr/include/flann/ext/lz4.h
$ sudo ln -s /usr/include/lz4hc.h /usr/include/flann/ext/lz4hc.h

● R3LIVE

$ cd ~/your_workspace/src
$ git clone https://github.com/hku-mars/r3live.git
$ cd ..
$ catkin build -DCMAKE_BUILD_TYPE=Release

● Trouble shooting for R3LIVE

• LiDAR incoming frame too old ...
  • Original Livox-ros-driver does not publish the data with ROS timestamp, but LiDAR time.
  • So, use modified livox-ros-driver here
  • If that does not solve the problem, edit lddc.cpp yourself, line 563:

  //livox_msg.header.stamp = ros::Time((timestamp - init_lidar_tim - packet_offset_time )  / 1e9 + init_ros_time);
    livox_msg.header.stamp = ros::Time::now();
    /**************** Modified for R2LIVE **********************/
    ros::Publisher *p_publisher = Lddc::GetCurrentPublisher(handle);
    if (kOutputToRos == output_type_)
    {
      p_publisher->publish(livox_msg);
    }
  

● How to properly set configuration for R3LIVE

• Camera calibration - use Kalibr or camera_calibration
  • Kalibr - refer original repo
  • camera_calibration - use as here
• Lidar-Camera calibration
  • Other spinning LiDARs are not supported yet (for RGB mapping), but try to use lidar_camera_calibration repo, if you want to.
  • For LiVOX LiDAR, use livox_camera_calib repo
    • Record a bag file of LiVOX LiDAR data and capture the image from RGB camera you use.
    • Convert a bag file into a PCD file with (change directories in the launch file):

    $ roslaunch livox_camera_calib bag_to_pcd.launch
    

    • Then, calibrate LiDAR and camera as (change directories in the launch and config files):

    $ roslaunch livox_camera_calib calib.launch
    

★Note: extrinsic rotational parameter from livox_camera_calib should be transposed in the r3live_config.yaml file. Refer my extrinsic result and r3live config file

Left: Target image. Right: Target PCD

Left: calibrated image and residuals. Right: calibrated image

Sensor configuration of mine: `Pixhawk4 mini` as an IMU, `FLIR Blackfly S USB3 (BFS-U3-04S2C-C)`, `LiVOX MID-70`

How to run

● check each of config files and launch files in the folders of this repo

Trouble shooting for Gazebo Velodyne plugin

• When using CPU ray, instead of GPU ray, height - width should be interchanged, I used this script file