  This paper presents a novel automatic calibration system to estimate the
extrinsic parameters of LiDAR mounted on a mobile platform for sensor
misalignment inspection in the large-scale production of highly automated
vehicles. To obtain subdegree and subcentimeter accuracy levels of extrinsic
calibration, this study proposed a new concept of a target board with embedded
photodetector arrays, named the PD-target system, to find the precise position
of the correspondence laser beams on the target surface. Furthermore, the
proposed system requires only the simple design of the target board at the
fixed pose in a close range to be readily applicable in the automobile
manufacturing environment. The experimental evaluation of the proposed system
on low-resolution LiDAR showed that the LiDAR offset pose can be estimated
within 0.1 degree and 3 mm levels of precision. The high accuracy and
simplicity of the proposed calibration system make it practical for large-scale
applications for the reliability and safety of autonomous systems.
