The Design Of Precision Measurement System Based On Grating Moire Fringe Subdivision Technology

Grating moire fringe subdivision technology is widely applied in the field of precision measurement. The amplitude division electronic subdivision technology with its circuit is simple, low cost advantages became more commonly used subdivision technology. However, the problem of nonlinear moire fringe signal in the process of amplitude division electronic subdivision technology need to be solved.The traditional tangent method in the process of moire fringe subdivision can reduce the nonlinear error in a certain degree, but it still can't meet the requirements of more precise measurement. In order to solve this problem to achieve the ultimate precision measurement purposes, in this paper, the A / D sampling reconstruction method is used to reduce nonlinear error.In this article, the traditional tangent method and new method of nonlinear error are analyzed by MATLAB firstly, it can be obtained that the A / D sampling reconstruction method to reduce the nonlinear error has a certain advantage. Then putting this method to apply to the precision of moire fringe measuring system in practice.Then, going on the overall design of this system according raster output moire actual situation according to the actual situation of output grating moire fringe,front-end processing circuit is designed to filter out the noise and the interference of the original signal. Besides, in order to realize precision measurement under the condition of high speed measuring, on the signal subdivision scheme design, the system adopt the way of the coarse and fine points parallel processing. In addition, in terms of software design, the segmentation algorithm is optimized, and the processing time is reduced, so the overall performance of the system have been further improved.Finally, the laser interferometer is used to test the calibration of this system.Then to analysis the repeatability error of experimental data by the method of DMRT.In addition, in the system error, resolution and other aspects of the system go on the further error analysis. In the end, it can be deter5 mined that the subdivision system is an acceptable precision measurement system.