A calibration method for spatial pose of a laser beam

Abstract

An articulated laser sensor, which is a new kind of trans-scale, non-contact metrological instrument, is principally made up of two articulated laser sensing modules. Each module is composed of two rotary tables and one collimated laser. Calibrating the spatial pose of a laser beam is a key aspect of the measurement system. In this paper we propose a one-dimensional linear displacement optical calibration device for high stability and easily performed calibration. Through analysis of space vectors and image processing, a calibration method for spatial pose of the laser beam is introduced in detail. The calibration method is divided into two parts: calibration of the direction vector of the laser beam and a fixed point on the laser beam. Firstly, the direction vector of the laser beam is calibrated using the proposed calibration device. Then a set of points on the laser beam is obtained and the linear fitting is performed. By comparing the direction vector of the fitted line and the direction vector of the above laser beam, the optimal fixed point on the fitted line is obtained. The simulation and experimental results show that the proposed calibration method is accurate and effective.