We have developed an automatic and accurate inspection system for LiDAR alignment for application in the automobile industry.

A misalignment of LiDAR as low as a few degrees could cause a significant error in obstacle detection and mapping that could cause safety and quality issues.

The proposed methods estimate the orientations and the horizontal position of the LiDAR attachment with sub-degree and millimeter level accuracy.

Oh, Seontaek, Ji-Hwan You, Azim Eskandarian, and Young-Keun Kim. “Accurate Alignment Inspection System for Low-Resolution Automotive LiDAR.” IEEE Sensors Journal 21, no. 10 (2021): 11961-11968.

It is a static method for the stationary target board and vehicle during the inspection.

Also, it only requires one pose of the target board and does not utilize other sensors, such as a camera or GPS.

The experimental results for a low-resolution 16 channel LiDAR (Velodyne VLP-16) confirmed that misalignment could be estimated with accuracy within 0.2 degrees and 4 mm.

You, Ji Hwan, Seontaek Oh, Jae Eun Park, Hyeongseok Song, and Young Keun Kim, ‘A Novel LiDAR Sensor Alignment Inspection System for Automobile Productions Using 1-D Photodetector Arrays’, Measurement, 183 (2021), 109817 https://doi.org/10.1016/J.MEASUREMENT.2021.109817

LiDAR extrinsic calibration using a target board with embedded photodetector arrays.

LiDAR sensor pose estimated within 0.1 degree and 3 mm of precision.

Requires a single target at static pose, applicable to manufacturing automobiles.

Song, H. S., You, J. H., Park, J. E., Eskandarian, A., & Kim, Y. K. (2021). Automatic inspection system for automotive LiDAR alignment using a cubic target. IEEE Sensors Journal, 22(3), 2793-2801.

The proposed inspection system is a one-shot and static method that uses only a single cubic-shaped target at a close range of less than 2 m.

The proposed method with a low-resolution LiDAR (Velodyne VLP-16) resulted in measurement errors of less than 0.04◦ and 1 mm for rotation and translation alignment, respectively.

H. -S. Song and Y. -K. Kim, "Automatic One-Shot LiDAR Alignment Inspection System Using NIR Camera," in IEEE Sensors Journal, vol. 23, no. 7, pp. 7798-7805, 1 April1, 2023, doi: 10.1109/JSEN.2023.3245219.