params.yaml

lio_sam:

  # Topics
  pointCloudTopic: "points_raw"               # Point cloud data
  imuTopic: "imu_raw"                         # IMU data
  odomTopic: "odometry/imu"                   # IMU pre-preintegration odometry, same frequency as IMU
  gpsTopic: "odometry/gpsz"                   # GPS odometry topic from navsat, see module_navsat.launch file

  # GPS Settings
  useImuHeadingInitialization: true           # if using GPS data, set to "true"
  useGpsElevation: false                      # if GPS elevation is bad, set to "false"
  gpsCovThreshold: 2.0                        # m^2, threshold for using GPS data
  poseCovThreshold: 25.0                      # m^2, threshold for using GPS data
  
  # Export settings
  savePCD: false                              # https://github.com/TixiaoShan/LIO-SAM/issues/3
  savePCDDirectory: "/Downloads/LOAM/"        # in your home folder, starts and ends with "/". Warning: the code deletes "LOAM" folder then recreates it. See "mapOptimization" for implementation

  # Sensor Settings
  N_SCAN: 16                                  # number of lidar channel (i.e., 16, 32, 64, 128)
  Horizon_SCAN: 1800                          # lidar horizontal resolution (Velodyne:1800, Ouster:512,1024,2048)

  # IMU Settings
  imuAccNoise: 3.9939570888238808e-03
  imuGyrNoise: 1.5636343949698187e-03
  imuAccBiasN: 6.4356659353532566e-05
  imuGyrBiasN: 3.5640318696367613e-05
  imuGravity: 9.80511

  # Extrinsics (lidar -> IMU)
  extrinsicTrans: [0.0, 0.0, 0.0]
  extrinsicRot: [-1, 0, 0,
                  0, 1, 0,
                  0, 0, -1]
  extrinsicRPY: [0,  1, 0,
                 -1, 0, 0,
                  0, 0, 1]
  # extrinsicRot: [1, 0, 0,
  #                 0, 1, 0,
  #                 0, 0, 1]
  # extrinsicRPY: [1, 0, 0,
  #                 0, 1, 0,
  #                 0, 0, 1]

  # LOAM feature threshold
  edgeThreshold: 1.0
  surfThreshold: 0.1
  edgeFeatureMinValidNum: 10
  surfFeatureMinValidNum: 100

  # voxel filter paprams
  odometrySurfLeafSize: 0.4                     # default: 0.4
  mappingCornerLeafSize: 0.2                    # default: 0.2
  mappingSurfLeafSize: 0.4                      # default: 0.4

  # robot motion constraint (in case you are using a 2D robot)
  z_tollerance: 1000                            # meters
  rotation_tollerance: 1000                     # radians

  # CPU Params
  numberOfCores: 4                              # number of cores for mapping optimization
  mappingProcessInterval: 0.15                  # seconds, regulate mapping frequency

  # Surrounding map
  surroundingkeyframeAddingDistThreshold: 1.0   # meters, regulate keyframe adding threshold
  surroundingkeyframeAddingAngleThreshold: 0.2  # radians, regulate keyframe adding threshold
  surroundingKeyframeDensity: 2.0               # meters, downsample surrounding keyframe poses   
  surroundingKeyframeSearchRadius: 50.0         # meters, within n meters scan-to-map optimization (when loop closure disabled)

  # Loop closure