PJLab-ADG / Livox-Mapping

An all-in-one and ready-to-use LiDAR-inertial odometry system for Livox LiDAR
BSD 3-Clause "New" or "Revised" License
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Parameters between Lidar and Imu/GNSS #16

Closed ManChrys closed 2 years ago

ManChrys commented 2 years ago

Hello,

i have a livox mid 40 and an INS/GNSS system (xsens mti g 710) . I would like to ask you whats these parameters mean

[0.997573, -0.024254, 0.065274, 0.322019, 0.023477, 0.999644, 0.012663, 0.043158, -0.066402, -0.011080, 0.997733, 0.456606, 0.0, 0.0, 0.0, 1.0]

I understand that some of them are the distances between lidar and imu but could you explain every number on this table what represents?

Thanks in advance.

SiyuanHuang95 commented 2 years ago

Hi,

Thanks for your interest in our project.

The T matrix contains the Rotation matrix and translation vector.

R = T [0:2, 0:2] t = T[0:2, 3]

so you would figure out that the rotation matrix is almost an identity matrix and translation vector is small.

Best

InterKnight commented 2 years ago

Hi,

Thanks for your interest in our project.

The T matrix contains the Rotation matrix and translation vector.

R = T [0:2, 0:2] t = T[0:2, 3]

so you would figure out that the rotation matrix is almost an identity matrix and translation vector is small.

Best

[0.997573, -0.024254, 0.065274, 0.322019, 0.023477, 0.999644, 0.012663, 0.043158, -0.066402, -0.011080, 0.997733, 0.456606, 0.0, 0.0, 0.0, 1.0]

that means 0.322019 is x translation, 0.043158 is y translation, 0.456606 is z translation ?

InterKnight commented 2 years ago

Hi,think you for great project. I have another question about parameters: why parameters in livox_odometry.launch is not same with that in livox_mapping.launch ?

SiyuanHuang95 commented 2 years ago

Hi, Thanks for your interest in our project. The T matrix contains the Rotation matrix and translation vector. R = T [0:2, 0:2] t = T[0:2, 3] so you would figure out that the rotation matrix is almost an identity matrix and translation vector is small. Best

[0.997573, -0.024254, 0.065274, 0.322019, 0.023477, 0.999644, 0.012663, 0.043158, -0.066402, -0.011080, 0.997733, 0.456606, 0.0, 0.0, 0.0, 1.0]

that means 0.322019 is x translation, 0.043158 is y translation, 0.456606 is z translation ?

@InterKnight Right

SiyuanHuang95 commented 2 years ago

Hi,think you for great project. I have another question about parameters: why parameters in livox_odometry.launch is not same with that in livox_mapping.launch ?

@InterKnight Usually the translation part does not affect the final result much. And the rotation part is almost identical.

InterKnight commented 2 years ago

Hi,think you for great project. I have another question about parameters: why parameters in livox_odometry.launch is not same with that in livox_mapping.launch ?

@InterKnight Usually the translation part does not affect the final result much. And the rotation part is almost identical.

thank you very much!

SiyuanHuang95 commented 2 years ago

When no further questions, I will close this issue.