How to get the translations for Lidar to imu calibration.

[UditSinghParihar]

Hi authors, Thanks for your wonderful work.

1. I would like to ask how you generate the translation for the lidar to imu calibration data since imu only gives only rotation messages and not translations. From the name of the text file, it seems like you are Novatel GPS/IMU unit, which gives fuses imu with the GPS messages to give a complete transformations matrix. Is my understanding correct, can you mention your sensor setup?

2. Also, should I manually need to extract the synchronized lidar point clouds and transformation matrices?

3. Also, how can I calibrate lidar to IMU and not the GPS fused imu?

[TongxingJin]

Hi authors, Thanks for your wonderful work.

1. I would like to ask how you generate the translation for the lidar to imu calibration data since imu only gives only rotation messages and not translations. From the name of the text file, it seems like you are Novatel GPS/IMU unit, which gives fuses imu with the GPS messages to give a complete transformations matrix. Is my understanding correct, can you mention your sensor setup?
2. Also, should I manually need to extract the synchronized lidar point clouds and transformation matrices?
3. Also, how can I calibrate lidar to IMU and not the GPS fused imu?

For 1, I think so, but I didn't get a good result until now using my own data, maybe it relies on the fine absolute pose from INS.

[qyj1996]

嗨，作者，感谢您的精彩工作。

1. 我想问一下，您如何生成激光雷达到imu校准数据的平移，因为imu只提供旋转消息，而不提供平移。从文本文件的名称来看，您似乎是Novatel GPS / IMU单元，它将imu与GPS消息融合在一起，以提供完整的转换矩阵。我的理解是否正确，您能提到您的传感器设置吗？
2. 另外，我是否需要手动提取同步的激光雷达点云和变换矩阵？
3. 另外，如何将激光雷达校准为IMU而不是GPS融合的imu？

嗨，作者，感谢您的精彩工作。

1. 我想问一下，您如何生成激光雷达到imu校准数据的平移，因为imu只提供旋转消息，而不提供平移。从文本文件的名称来看，您似乎是Novatel GPS / IMU单元，它将imu与GPS消息融合在一起，以提供完整的转换矩阵。我的理解是否正确，您能提到您的传感器设置吗？
2. 另外，我是否需要手动提取同步的激光雷达点云和变换矩阵？
3. 另外，如何将激光雷达校准为IMU而不是GPS融合的imu？

对于1，我认为是这样，但是直到现在我才使用自己的数据获得好的结果，也许它依赖于INS的精细绝对姿势。

Hi authors, Thanks for your wonderful work.

1. I would like to ask how you generate the translation for the lidar to imu calibration data since imu only gives only rotation messages and not translations. From the name of the text file, it seems like you are Novatel GPS/IMU unit, which gives fuses imu with the GPS messages to give a complete transformations matrix. Is my understanding correct, can you mention your sensor setup?
2. Also, should I manually need to extract the synchronized lidar point clouds and transformation matrices?
3. Also, how can I calibrate lidar to IMU and not the GPS fused imu?

For 1, I think so, but I didn't get a good result until now using my own data, maybe it relies on the fine absolute pose from INS.

嗨，作者，感谢您的精彩工作。

1. 我想问一下，您如何生成激光雷达到imu校准数据的平移，因为imu只提供旋转消息，而不提供平移。从文本文件的名称来看，您似乎是Novatel GPS / IMU单元，它将imu与GPS消息融合在一起，以提供完整的转换矩阵。我的理解是否正确，您能提到您的传感器设置吗？
2. 另外，我是否需要手动提取同步的激光雷达点云和变换矩阵？
3. 另外，如何将激光雷达校准为IMU而不是GPS融合的imu？

对于1，我认为是这样，但是直到现在我才使用自己的数据获得好的结果，也许它依赖于INS的精细绝对姿势。

Hi authors, Thanks for your wonderful work.

1. I would like to ask how you generate the translation for the lidar to imu calibration data since imu only gives only rotation messages and not translations. From the name of the text file, it seems like you are Novatel GPS/IMU unit, which gives fuses imu with the GPS messages to give a complete transformations matrix. Is my understanding correct, can you mention your sensor setup?
2. Also, should I manually need to extract the synchronized lidar point clouds and transformation matrices?
3. Also, how can I calibrate lidar to IMU and not the GPS fused imu?

For 1, I think so, but I didn't get a good result until now using my own data, maybe it relies on the fine absolute pose from INS.

Hello, now I need to calibrate the external parameters of my lidar and inertial navigation system, but I don't know how to obtain the data required by the tool. I hope I can have in-depth communication with you and ask you some questions. If you can spare me your advice, I will be grateful. Of course, I can also give you paid guidance.

[UditSinghParihar]

@qyj1996 , I would suggest using lidar_imu_calib package for imu lidar calibration. lidar_imu_calib would give you rotation extrinsic between lidar and imu and it directly subscribe the ROS topics.

1. First of all you need to ensure whether you have a 6-axis or 9-axis IMU.
2. Whether you have Novatel GPS fused imu, which gives you orientation and translation both.

Feel free to reach out to me at uditsinghparihar96@gmail.com, if you face any issues.

[qyj1996]

@qyj1996 , I would suggest using lidar_imu_calib package for imu lidar calibration. lidar_imu_calib would give you rotation extrinsic between lidar and imu and it directly subscribe the ROS topics.

1. First of all you need to ensure whether you have a 6-axis or 9-axis IMU.
2. Whether you have Novatel GPS fused imu, which gives you orientation and translation both.

Feel free to reach out to me at uditsinghparihar96@gmail.com, if you face any issues.

Thank you very much for your reply. I'll try this method right away, but I don't know how to adapt my own dataset. My lidar is velodyne vls128. Can I use method lidar_imu_calib and how to adapt my own dataset? Please give me your advice.