zijiechenrobotics / ig_lio

iG-LIO: An Incremental GICP-based Tightly-coupled LiDAR-inertial Odometry
GNU General Public License v2.0
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About NCLT Dataset ground truth #19

Open Liming-Cheng opened 4 months ago

Liming-Cheng commented 4 months ago

Hi author, thanks for the great work! I am confused about the coordinate system of the ground_truth.csv provided by NCLT. As far as I know, the IMU attitude is transformed to the LiDAR coordinate system in the script. The trajectory should be in the transformed coordinate system. Is there any script or method to generate ground_truth.txt of the NCLT Dataset in the IMU coordinate system?

Another question about nclt extrinsic parameter for lidar-->imu: t_imu_lidar : [0, 0, 0.28] R_imu_lidar : [1, 0, 0, 0, 1, 0, 0, 0, 1] Is this extrinsic parameter really correct?

In liw-oam project(https://github.com/ZikangYuan/liw_oam) , the extrinsic is set as: T_IMU_LIDAR = [[1, 0, 0, 0.112], [0, 1, 0, 0.176], [0, 0, 1, -0.247], [0, 0, 0, 1]]