The Technology And Application Of 3D Profile Surface Measurement Based On Optical Fiber Sensor

With the progress of the times and the updating of science and technology, China’s machinery manufacturing has been booming development, putting forward higher requests to the detection technology of the parts’surface. Detecting on the internal and outer contour surface of the parts is gradually developing into high-precision and digital detection, then the direct contact with the surface being measured by gauges contacting with the surface directly and the non-contact method based on the photoelectric and electromagnetic technology were emerged. This paper is mainly based on the profile of the parts’surface, established a micro displacement platform to detect the quality of the parts’surface based on optical fiber sensor. It provides a new effective means to further realization of digital detection of parts’contour surface, and it has important theoretical guiding significance and wide application prospects.Firstly, this paper discusses the research purpose and meaning of the subject, and respectively describes the general situation of the development of the detection technology of part contour surface and optical sensor technology, learning from experiences and putting forward the program to detect the parts’surface using fiber optic sensors. After classifying fiber optical sensors according to the modulation characteristics, this paper mainly focuses on the intensity modulated optical fiber sensor used herein, and analyzes the basic principle of detecting displacement, and conclude that if the fiber core diameter and other conditions remain unchanged, optical coupling efficiency only has relation with the displacement of the measured surface based on the output optical field distribution of optical fiber sensor, providing a theoretical support for the detection of surface profile.Secondly, the paper makes a theoretical description of the measurements of surface profile detection using of optical fiber displacement sensor in detail, and puts forward the path planning method of fiber optic sensor probe in the detection process. After analyzing the analysis of the light source, light detector and optical fiber of the optical fiber sensor, it gives the detection scheme of the surface profile based on the optical fiber displacement sensor, and built the experimental platform. According to the principle of detection, it designs corresponding circuit to amplify, filter and divide the weak signal of the sensor, obtaining a higher noise ratio signal.Finally, this paper proposes a nonlinear processing scheme based on radial basis function network (RBF) after analysing the relevant theories of neural network, and carries the simulation experiments on the designed RBF neural network. The graphic shows that the training of RBF neural network has good fitting effect since it can approximate the nonlinear function better. At the end of this paper, it carries a three-dimensional topography measurement on a piece of steel sheet and coin based on the designed scheme and established experimental platform, then it summarizes the shortcomings of experiment and looks into the distance for the further research.