To detect the 3D data of the part, the specific process is to detect the surface geometry of the part and convert it into spatial coordinates. The final coordinate points obtained in the process of data detection are the data basis of the whole reverse engineering modeling and evaluation.

Therefore, the selection of detection methods and equipment in the measurement process is particularly important, which is a prerequisite for reverse engineering. It not only affects the efficiency of reverse engineering, but also directly determines the quality of reverse engineering. The reverse engineering specific data detection methods are divided into contact and non-contact.

Among them, the contact type means that when the probe contacts with the surface of the object to be measured, a corresponding coordinate value will be recorded, and all the spatial coordinates of the part to be measured will be obtained through multiple measurements; the non-contact type is gradually widely used with the rapid development of optical and electronic components, and this method mainly applies the principles of acoustics, optics, electromagnetics, etc., by converting the physical analog quantity into digital After a certain algorithm, it is converted to the space coordinate value.

Three coordinate measuring machine and robot arm measuring machine adopt contact measuring method, while laser triangle method, structured light distance measuring method and industrial CT chromatography are non-contact measuring methods.