# FAST\_LIO\_LC

## What is FAST\_LIO\_LC?

- A computationally efficient and robust LiDAR-inertial odometry package with loop closure module and graph optimization.

## Repository Information

### Original Repository link

[https://github.com/yanliang-wang/FAST\_LIO\_LC](<https://github.com/yanliang-wang/FAST_LIO_LC>)

### Required Sensors

- LIDAR \[Velodyne, Ouster, Livox\]
- IMU \[6-AXIS, 9-AXIS\]
- GPS \[Optional\]

### ROS Compatibility

- ROS 1

### Dependencies

- Ubuntu 18.04
- ROS Melodic
- PCL \>= 1.8, Follow [PCL Installation](<https://pointclouds.org/downloads/#linux>).
- Eigen \>= 3.3.4, Follow [Eigen Installation](<https://libeigen.gitlab.io/eigen/docs-3.3/>).
- GTSAM \>= 4.0.0, Follow [GTSAM Installation](<https://gtsam.org/get_started>).

```bash
  wget -O ~/Downloads/gtsam.zip https://github.com/borglab/gtsam/archive/4.0.0-alpha2.zip
  cd ~/Downloads/ && unzip gtsam.zip -d ~/Downloads/
  cd ~/Downloads/gtsam-4.0.0-alpha2/
  mkdir build && cd build
  cmake ..
  sudo make install
```

## Build &amp; Run

### 1\) Build

```bash
    mkdir -p ~/ws_fastlio_lc/src
    cd ~/ws_fastlio_lc/src
    git clone https://github.com/yanliang-wang/FAST_LIO_LC.git
    cd ..
    catkin_make
```

### 2\) Set parameters

- After downloading the repository, change topic and sensor settings on the config file (`workspace/src/FAST_LIO_LC/FAST-LIO/config/ouster64_mulran.yaml`) with the lidar topic name in your bag file.

- For imu-lidar compatibility, extrinsic matrices from calibration must be changed.

- To enable auto-save, `pcd_save_enable` must be `1` from the launch file (`workspace/src/FAST_LIO_LC/FAST-LIO/launch/mapping_ouster64_mulran.launch`).

### 3\) Run

- For Ouster OS1-64

  ```
  # open new terminal: run FAST-LIO
  roslaunch fast_lio mapping_ouster64_mulran.launch

  # open the other terminal tab: run SC-PGO
  roslaunch aloam_velodyne fastlio_ouster64.launch

  # play bag file in the other terminal
  rosbag play RECORDED_BAG.bag --clock
  ```

## Example Result

## Other Examples

## Example dataset

Check original repository link for example dataset.

## Contact

- Maintainer: Yanliang Wang (`wyl410922@qq.com`)

## Acknowledgements

- Thanks for [FAST\_LIO](<https://github.com/hku-mars/FAST_LIO>) authors.