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Extrinsic Calibration of 2D Laser Rangefinders Using Indoor Geometric Constraints

Laser rangefinders are widely used in navigation, mapping and SLAM systems, while the extrinsic calibration is the key factor of their performance. An extrinsic calibration method of multiple 2D laser rangefinders using indoor geometric constraints is proposed. Taking one common indoor corridor as the calibration environment, the co-planarity constraint and the orthogonality constraint are used to convert the calibration problem to a nonlinear optimization problem, which is solved by Levenberg-Marquardt. A co-planarity assessment method based on the volume of tetrahedron consisted by line pairs is proposed to improve the stability of finding correct corridor observations. Experimental results are presented to validate the method.