Research on the calibration of the rotating axis of five-axis platform based on monocular vision and product of exponentials formula

Abstract

In this paper, a method to realize the geometric error calibration of the rotation axis by using the monocular camera is proposed. Based on the product of exponentials formula, the proposed scheme carries out kinematic modeling for the rotation axis of the five-axis motion platform and deduces the calculation method of geometric error at each position. The calibrated error includes the axis direction error, position error, and rotation angle measurement error. According to the proposed technique, the geometric error of the two rotating axes of the platform is calibrated. Finally, the workspace of the two rotating axes of the platform is uniformly sampled to detect the calibration accuracy. The experimental results show that the proposed method effectively reduces the average position error of turntable from 0.0791 mm before identification to 0.0186 mm and the average orientation error from 0.0030 rad to 0.0008 rad.