Research On Non-Contact Visual Inspection System Of Geometric Dimension Based On LabVIEW And IMAQ Vision

As the development of advanced modern manufacturing technology, the measurement technology is required to develop in the direction of high precision, high speed and network. The traditional inspection methods can't meet the need of modern manufacturing. The non-contact measuring method based on machine vision has become an important development direction of precise measurement technology in the new age.Since the theory of VI (Virtual Instrument) was established in 1980s, VI technology has been applied in producing measurement. It has great advantages on flexibility of measurement tasks, convenience of system design and the low coast. The machine vision system designed by other software is very difficult to program and modify, and the machine vision system based on virtual instrument has solved this problem to some extent, which meet the need of machine vision development: to be faster, cheaper, exacter and more reliable. Now, the machine vision system based on virtual instrument can carry out more complex inspection task due to its high efficiency, flexibility, consistency, reliability and data throughput ability.In order to design a visual inspection system based on virtual instrument to measure the size of a cuboid, this paper has done the work as follows:First, the essential principles of the visual inspection system based on virtual instrument were introduced, which include the principles of virtual instrument technology and that of the stereo visual inspection. On the aspect of virtual instrument, the development platform LabVIEW and the image processing software package IMAQ Vision were also introduced. On the aspect of stereo visualinspection, each step of the whole system-image preprocessing, imagesegmentation, edge detection, corner point extraction, stereo matching and 3 dimensional reconstruction- was explained in detailed.Then, the design of the visual inspection system based on virtual instrument was illustrated, which included the hardware design and the software design as a whole and in detailed. And the program was written in LabVIEW and IMAQ Vision.At last, the experimental analysis was done. The size of the cuboid was computed. It was proved by the experiment that the visual inspection system based on virtual instrument can process kinds of image processing and the measurement error was less than 4.5%.The design of visual inspection system brought forward an idea and method on design of the stereo machine vision system based on LabVIEW and IMAQ Vision, and it is hoped to provide a significative reference for the research of machine vision based on LabVIEW and IMAQ Vision.