extrinsic matrix between lidar and imu

[mz7790]

This dataset is good, but there are currently some doubts about the extrinsic matrix between sensors May I ask if the extrinsic matrix between lidar and imu in campus_road_camera.bag refers to the base_to_imu in the parking lot, or is imu considered to be in the base coordinate system? Here is my simple code for converting lidar to imu coordinate systems, I'm not sure if it's correct

import numpy as np from scipy.spatial.transform import Rotation as R #Transformation from base to lidar Rpy_lidar=[-0.05235, 0.005, -0.003] Rotation_lidar=R. from_euler ('xyz ', rpy_lidar, degrees=False) R_lidar=rotation_lidar. as_matrix() Tlidar=np. array ([-0.09, 0, 1.06]) #Transformation from base to imu T-imu=np. array ([-0.05, 0.00, 0.35]) Rpy_imu=[0.00, 0.00, 0.00] Rotation_imu=R.free_euler ('xyz ', rpy_imu, degrees=False) R_imu=rotation_imu. as_matrix() #Create 4x4 transformation matrices Tcase_to_lidar=np. eye (4) TBase_to_lidar [: 3,: 3]=R_lidar Tbase_to_lidar [: 3, 3]=tlidar Tcase_to_imu=np. eye (4) TBase_to_imu [: 3,: 3]=R_imu Tbase_to_imu [: 3, 3]=t_imu #Compute the inverse transformation from base to imu Tcase_to_imu_inv=np. final. inv (Tcase_to_imu) #Compute the transformation from lidar to imu Tlidar_to_imu=np. dot #Extract rotation matrix and translation vector R_lidar_to_imu=Tlidar_to_imu [: 3,: 3] Tlidar_to_imu=Tlidar_to_imu [: 3, 3] Print ("Rotation matrix from lidar to imu (R):") Print (R_lidar_to_imu) Print ("Translation vector from lidar to imu (T):") Print (tlidar-to_imu)

Rotation matrix from lidar to imu (R): [9.71213646e-01 1.59993173e-02 2.37672201e-01] [-1.55407445e-02 9.9987203e-01-3.80307975e-03] [-2.37702626e-01-2.16840434e-19 9.71337975e-01] Translation vector from lidar to imu (T): [0.09 0 0.222]