Robosen lidar calib result ！！！

[MrDragon2]

Hi author,
I calibrated with Robosen lidar(32lines) and IMU, but the result is incorrect：
LiDAR-IMU calibration result:
Rotation LiDAR to IMU (degree) = 0.001848 -0.314683 109.471282
Translation LiDAR to IMU (meter) = 0.131908 -0.216292 -0.840857
Time Lag IMU to LiDAR (second) = -0.161370
Bias of Gyroscope (rad/s) = -0.000975 -0.001078 0.000365
Bias of Accelerometer (meters/s^2) = -0.006084 -0.012796 0.006816

  Homogeneous Transformation Matrix from LiDAR frmae L to IMU frame I: 
  -0.333197 -0.942856  0.001860  0.131908
   0.942841 -0.333202 -0.005167 -0.216292
   0.005492  0.000032  0.999985 -0.840857
   0.000000  0.000000  0.000000  1.000000

What is the problem with the obvious incorrect result of this rotation and translation matrix?

[MrDragon2]

[Data accumulation] Rotation around Lidar X Axis complete!
[Data accumulation] Rotation around Lidar Y Axis complete!
[Data accumulation] Rotation around Lidar Z Axis: 85% [||||||||||||||||||||||||| ]
[Rotation matrix Ground to LiDAR (euler)] 0.1033 -1.08 -0.0009733 deg
[Rotation matrix Ground to IMU (euler)] 0.09112 -0.4713 91.48 deg
[Estimated LiDAR sensor height] : 0.3132 m
[laserMapping-3] process has died [pid 1713835, exit code -11, cmd /home/lgg/catkin_ws/devel/lib/gril_calib/gril_calib __name:=laserMapping __log:=/home/lgg/.ros/log/b704e392-b20c-11ef-9c2d-1f1a0c2c2551/laserMapping-3.log].
log file: /home/lgg/.ros/log/b704e392-b20c-11ef-9c2d-1f1a0c2c2551/laserMapping-3*.log

The program crashed！！！？？？？

[MrDragon2]

[Data accumulation] Rotation around Lidar X Axis complete! [Data accumulation] Rotation around Lidar Y Axis complete! [Data accumulation] Rotation around Lidar Z Axis: 85% [||||||||||||||||||||||||| ] [Rotation matrix Ground to LiDAR (euler)] 0.1033 -1.08 -0.0009733 deg [Rotation matrix Ground to IMU (euler)] 0.09112 -0.4713 91.48 deg [Estimated LiDAR sensor height] : 0.3132 m [laserMapping-3] process has died [pid 1713835, exit code -11, cmd /home/lgg/catkin_ws/devel/lib/gril_calib/gril_calib __name:=laserMapping __log:=/home/lgg/.ros/log/b704e392-b20c-11ef-9c2d-1f1a0c2c2551/laserMapping-3.log]. log file: /home/lgg/.ros/log/b704e392-b20c-11ef-9c2d-1f1a0c2c2551/laserMapping-3*.log

The program crashed！！！？？？？

I am using lidar is Helios 32

[Taeyoung96]

@MrDragon2

Thanks for interesting our work!

1. The calibration results will depend on how you acquired the data: you should utilize figure-of-eight motion to acquire the data, and make sure that the ground is reliably estimated. You should also check parameters in the config file, such as the height of the IMU, LiDAR height, etc.

2. Unfortunately, I haven't experimented with Helios 32 yet, so I'm curious to know what modifications you've made and what results you've seen. Does it always crash? Or does it only happen occasionally?

[MrDragon2]

@MrDragon2

Thanks for interesting our work!

1. The calibration results will depend on how you acquired the data: you should utilize figure-of-eight motion to acquire the data, and make sure that the ground is reliably estimated. You should also check parameters in the config file, such as the height of the IMU, LiDAR height, etc.
2. Unfortunately, I haven't experimented with Helios 32 yet, so I'm curious to know what modifications you've made and what results you've seen. Does it always crash? Or does it only happen occasionally?

The sensor parameters you mentioned have already been set, and I will reduce the parameter 'z'accumulate' and it will not crash；z_accumulate : 0.3 #0.99

But the result still has a large margin of error：
Homogeneous Transformation Matrix from LiDAR frmae L to IMU frame I:
-0.234803 -0.972043 0.000229 -0.046851
0.972032 -0.234801 -0.004810 -0.374820
0.004729 -0.000907 0.999988 -0.841409
0.000000 0.000000 0.000000 1.000000

[MrDragon2]

[Data accumulation] Rotation around Lidar X Axis complete! [Data accumulation] Rotation around Lidar Y Axis complete! [Data accumulation] Rotation around Lidar Z Axis: 85% [||||||||||||||||||||||||| ] [Rotation matrix Ground to LiDAR (euler)] 0.1033 -1.08 -0.0009733 deg [Rotation matrix Ground to IMU (euler)] 0.09112 -0.4713 91.48 deg [Estimated LiDAR sensor height] : 0.3132 m [laserMapping-3] process has died [pid 1713835, exit code -11, cmd /home/lgg/catkin_ws/devel/lib/gril_calib/gril_calib __name:=laserMapping __log:=/home/lgg/.ros/log/b704e392-b20c-11ef-9c2d-1f1a0c2c2551/laserMapping-3.log]. log file: /home/lgg/.ros/log/b704e392-b20c-11ef-9c2d-1f1a0c2c2551/laserMapping-3*.log
The program crashed！！！？？？？

I am using lidar is Helios 32

I use the function package rs_to_velodyne to convert Robosen's data into velodyne.

[Taeyoung96]

@MrDragon2
z_accumulate is simply a threshold to accumulate data.
If you have a reliable initial value for the translation vector, we recommend replacing set_boundary : true``bound_th : 0.1 in the yaml file and experimenting.

[MrDragon2]

@MrDragon2 z_accumulate is simply a threshold to accumulate data. If you have a reliable initial value for the translation vector, we recommend replacing set_boundary : truebound_th : 0.1 `` in the yaml file and experimenting.

Homogeneous Transformation Matrix from LiDAR frmae L to IMU frame I:
-0.276476 -0.961020 -0.000955 -0.068680
0.960989 -0.276459 -0.008391 -0.125725
0.007800 -0.003237 0.999964 0.234888
0.000000 0.000000 0.000000 1.000000
The result is incorrect.......

[ZhongbiLuo]

@MrDragon2 z_accumulate is simply a threshold to accumulate data. If you have a reliable initial value for the translation vector, we recommend replacing set_boundary : truebound_th : 0.1 `` in the yaml file and experimenting.

Homogeneous Transformation Matrix from LiDAR frmae L to IMU frame I: -0.276476 -0.961020 -0.000955 -0.068680 0.960989 -0.276459 -0.008391 -0.125725 0.007800 -0.003237 0.999964 0.234888 0.000000 0.000000 0.000000 1.000000 The result is incorrect.......

Hello, I am also trying to calibration Robosen Helios 32, I would like to know if you have successfully calibrated it with this method? Or do you use other methods? Thank you so much!!

[WangLu180]

Have you solve it brother？I also get this problem with Robosen Helios 32. i drive the car like 8 to calib