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Calibration Method of Three Dimensional (3D) Laser Measurement System Based on Projective Transformation

According to planar projective transformation theory, a calibration method of the three dimensional (3D) laser measurement system is put forward to application in this paper. A key contribution of the method lies in the derivation of transformation relations that describe the same point in three defined coordinate systems with respect to the rotating characteristic of two scanning planes and its calibration target object whose geometric feature can be reliably recognized from a single observation. The transformation relationship can be converted to the closed-form solution to the constraint equations of the system parameters in the form of intrinsic and extrinsic matrices. By deriving the relationship between a single two-dimensional range scan and the point location presentation in the absolute frame, the interior and exterior calibration can be accomplished simultaneously and the algorithm of the 6 DOF pose improves the identification precision. Finally, this paper report performance and stability of the calibration method on real data sets, and demonstrate accuracy within ±0.1 degree of the orientation precision and 8mm of position precision in a realistic configuration.