Config file after calibration

[ManChrys]

Hello guys and thanks again for the great projects.

After i use LiDAR_IMU_Init i got the initialization.txt

Refinement result: Rotation LiDAR to IMU (degree) = 1.920841 0.100224 0.280654 Translation LiDAR to IMU (meter) = 0.018073 -0.065269 0.149609 Time Lag IMU to LiDAR (second) = 1661782715.179687

on extrinsic_T: i put the 0.018073 -0.065269 0.149609 on time_offset_lidar_to_imu: i put the 1661782715.179687 but how can i put the rotation data to extrinsic_R so i can have the matrix in a correct format ? Should be a [3x3] table like in the example or just like txt [1x3] table?

Thanks in advance.

[zfc-zfc]

table initialization.txt of LiDAR-IMU_Init would give both rotation matrix and Euler angles. FAST-LIO needs rotation matrix format, which is a 3x3 matrix.

[ManChrys]

Hello @zfc-zfc and thanks for the answer,

the

Homogeneous Transformation Matrix from LiDAR to IMU: 0.997911 -0.062895 0.014785 -0.147775 0.063313 0.997551 -0.029731 -0.055362 -0.012879 0.030605 0.999449 -0.044644 0.000000 0.000000 0.000000 1.000000

is a 4x4 matrix which contain rotations from Lidar to Imu and the 3d vector (translation) between lidar and imu.

So if am right it has possibly the format

so the last column is the translation and its a [1,3] table and rotation matrix is a [3x3] table as you can see below:

extrinsic_T: [ -0.147775, -0.055362, -0.044644] extrinsic_R: [ 0.997911, -0.062895, 0.014785, 0.063313, 0.997551, -0.029731, -0.012879, 0.030605, 0.999449]

Please correct me if my wrong.

Thanks in advance.

[zfc-zfc]

translation

That's correct.

[ManChrys]

translation

That's correct.

Rotations are correct too right? Am asking because you quote only translation.

[zfc-zfc]

Both correct. The quote is automatically generated by github.

[ManChrys]

Thank you my friend!!! :D