This repository is the implementation of our paper "Ct-LVI: A Framework Towards Continuous-time Laser-Visual-Inertial Odometry and Mapping".

A running demo can be found at https://cslinzhang.github.io/Ct-LVI/Ct-LVI.html

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Prerequisites

• Install depends follow the instructions of "cartographer" and "cartographer_ros" respectively.

• Build OpenCV 3.3.1 (other version may work fine if it includes implementation of SURF keypoint detector) from source with "opencv_contrib"

• Build GTSAM 4.0.2 with compile options as follows:

  cmake -DGTSAM_USE_SYSTEM_EIGEN=ON -DGTSAM_WITH_TBB=OFF -DGTSAM_BUILD_WITH_MARCH_NATIVE=OFF -DGTSAM_COMPILE_OPTIONS_PUBLIC="" ..

• Build PCL 1.8.0 with compile options as follows:

  cmake -DPCL_ENABLE_SSE=OFF ..

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Build

• Clone this repository in your ROS workspace

• Set CMake variable "OpenCV_DIR" in the root CMakeLists.txt of "cartographer".

• Return to the root folder of your ROS workspace (which has the same directory as this "README" file) and run:

  catkin_make_isolated
  

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Run an online demo

Our HD Dataset

• Some demo sequences can be downloaded via:

  • HD dataset: link, pwd: bsqi

• Set the file path parameters (TRAJECTORY_BUILDER_3D.lvio_config_filename, POSE_GRAPH.camera_intrinsics_filename, and POSE_GRAPH.dbow_voc_filename) of the config file (tongji.lua)

• roslaunch ctlvi demo_ctlvi_tongji.launch bag_filename:=BAG_FILE_PATH where BAG_FILE_PATH is the full path of the downloaded bag file in your device

• Some results on the self-collected HD dataset.

  
  

NTU-VIRAL

• The dataset is available online at NTU-VIRAL

• Set the file path parameters (TRAJECTORY_BUILDER_3D.lvio_config_filename, POSE_GRAPH.camera_intrinsics_filename, and POSE_GRAPH.dbow_voc_filename) of the config file (viral.lua)

• ```roslaunch ctlvi demo_ctlvi_viral.launch bag_filename:=BAG_FILE_PATH```
  

  where BAG_FILE_PATH is the full path of the downloaded bag file in your device

• Results on VIRAL
  

  

Your own data

• Write a urdf file of your device and save it to folder 'urdf'
• Write a configuration file of your data and save it to 'config'
• Write a launch file of your data and save it to 'launch'
• Run your bag as above examples

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Run offline and view mapping result

Launch dlio offline

roslaunch ctlvi ctlvi_offline_tongji bag_filenames:=BAG_FILE_PATH

View mapping result

roslaunch ctlvi ctlvi_map_viewer_rectified urdf_filename:=tongji pose_graph_pb_filename:=PG_FILENAME range_data_pb_filename:=RD_FILENAME rate:=100

where PG_FILENAME and RD_FILENAME are binary pbstream files saved to disk when launch the offline script above.

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Acknowledgements

• The authors of cartographer
• The authors of cartographer_ros
• The authors of LVI-SAM
• The authors of VINS-Mono
• The authors of CLINS

License

Following the licenses of the above acknowledged repositories.