Key Technology Research Of Binocular Grating Projection

Grating projection is the most widely used in the three-dimensional topography measurement technology,which has a wide application prospect in many domains such as industrial inspection, quality control, reverse design, medical digital, virtual reality, cultural relics and human body measurement. Because of the advantages of its simple principle, easy implementation, fast measurement, high measuring accuracy and low cost,it widely used in engineering application. Compared with single grating projection system optical path needing a very stringent requirements, the binocular grating projection method is simple in principle. The binocular grating projection method don’t need to measur the geometric constraint between camera and a projector in advance and it has a very high flexibility. So the binocular grating projection has important theoretical significance and practical application value.This paper mainly stud y the object to be tested by the binocular grating projection reconstruction method by studying four typical time phase unwrapping algorithms contrastively,analyzing and comparing the phase unwrapping precision of the four methods using simulation raster images. For the problem of two-dimensional phase feature matching time overhead,this paper proposes a feature points matching algorithm searching in the neighborhood. The algorithm using the neighborhood relationship between matching points to lock the search scope in a small area,which reduces the matching algorithm time complexity greatly. Using the theory of finite state machine, classifying points can solve disconnected area matching failure. Using a standard object measurement precision of matching algorithm compared with the feature points matching algorithm based on the limit constraint. The experimental results show that this paper ’s algorithm has high matching precision and low time complexity. The matching results of the algorithm can be used to calculate parameters of exterior orientation.On the basis of theory research and practice in camera calibration, phase unwrapping, feature point matching and r econstruction of point cloud and display,a system developed based on binocular grating projection reconstruction and measurement.A configuration file way of software development makes the system a strong extensibility.