This paper discusses the measurement precision loss problem introduced by the inconsistent between measurement space and calibration space and presents a hybrid calibration method to solve this problem. The proposed method establishes the hybrid adjustment model based on the ray intersection constraint, ruler length constraint, and sparse control points' rescan constraint. The Levenberg-Marquardt algorithm is employed to solve the objective function. The initial value is calculated in two steps, in which the ruler length constraint is used to calculate the relationship between each transmitter, and the global coordinate system's transformation parameter is calculated by space intersection. In addition, the part of the adjustment objective function introduced by the ray intersection constraint is extended by considering the ray intersection constraint of the measured point. About 78% improvement in measurement accuracy is achieved compared with the traditional way.
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