calibration/run/rtk_lidar_mechanical_initial.json

{
  "schema_version": 3,
  "convention": "T_RTK_lidar maps raw LiDAR points into the vehicle-forward RTK body frame (X forward, Y left, Z up) after HeadingOffsetDeg=-90",
  "frame_mode": "vehicle_forward_heading_offset",
  "heading_offset_deg": -90.0,
  "baseline_points": "vehicle_right",
  "baseline_points_note": "Field-confirmed: master/slave assignment reversed vs G90 diagram, antennas left-right symmetric about rear-axle centerline. Master/GGA on vehicle left, slave on right; rawHeading points vehicle right.",
  "vehicle_flu_lever_master_to_lidar_m": [
    0.210859360,
    -0.414179474,
    0.078500001
  ],
  "vehicle_flu_note": "Vehicle FLU: LiDAR origin relative to master/GGA = ahead, right, above. CAD drawing X was opposite vehicle-forward; longitudinal sign is +X in true FLU (solver also converges to +X).",
  "antenna_symmetry_note": "Master/slave are mirrors about the rear-axle centerline; swap flips baseline 180° and the vehicle-Y sign of the master→LiDAR lever",
  "translation_m": [
    0.210859360,
    -0.414179474,
    0.078500001
  ],
  "rotation_rpy_deg_xyz": [
    0.0,
    0.0,
    0.0
  ],
  "matrix_4x4": [
    [1.0, 0.0, 0.0, 0.210859360],
    [0.0, 1.0, 0.0, -0.414179474],
    [0.0, 0.0, 1.0, 0.078500001],
    [0.0, 0.0, 0.0, 1.0]
  ],
  "use": "Final AX=XB solver initialization only; never use for LiDAR pair registration",
  "yaw_note": "In vehicle-forward delivery, LiDAR +X ≈ vehicle forward ⇒ mechanical yaw ≈ 0",
  "z_note": "78.500001 mm = H_L - H_R with H_L=1994.999879 mm, H_R=1916.499878 mm",
  "attitude_composition": "R_W_body = Rz(yaw_raw) Ry(-pitch) Rx(roll) Rz(-heading_offset); pitch/roll stay in baseline frame",
  "baseline_frame_equivalent": {
    "heading_offset_deg": 0.0,
    "translation_m": [0.414179474, 0.210859360, 0.078500001],
    "rotation_rpy_deg_xyz": [0.0, 0.0, 90.0],
    "note": "Same physical install expressed in rawHeading baseline frame"
  }
}