Three-Dimensional Measurement System for Inner Surface of Long Tubular Parts Based on White Light Interference.

In this paper, a 3D measurement system for the inner surface of tubular parts with large length-to-diameter ratio based on white light interference is developed. A common-path white light interferometer is built, and a side-looking probe which can obtain the reflected light of fiber end and can change the length freely is designed. In order to meet the requirements of large depth inner surface measurement, an inverted U-shaped combined device is designed and its geometric principle is described. With the aid of high-precision and large stroke 3-axis motion system, the 3D inner surface measurement is realized. The method of creating 3D point cloud, the correction method of probe center position, pose and light direction and the calibration method of system are described. The experimental results show that the system has a good inner diameter measurement accuracy, and is suitable for measuring the inner surface of long tubular parts.