Research Of Workpiece Machining Size Online Measurement System And Method Based On Machine Vision

Measurement is an important way of data acquisition in manufacturing, as well as the key process flow of the manufacturing process,which decides the quality of the product. The development of advanced manufacturing technology needs high precision, high efficiency, good flexibility measurement.The way of the traditional product size measurement stayed in artificial detection, simple mechanical device testing, optical instrument testing level whose measurement efficiency and accuracy has failed to keep pace with the rhythm of scientific research,testing and production.The online measurement system which is used to measure workpiece machining size based on machine vision introduced vision measurement technology into the machining process.By collecting the workpiece images and then processing them,we can extract workpiece edge profile, and then calculate dimensions.This system can effectively improve the efficiency and accuracy of measurement using real-time and flexible characteristics of the machine vision.Departure from the machine vision technology,a detailed description of vision measurement technology's applications in the online measuring workpiece machining dimensions is given, camera measurement process and algorithm is studied primarily,and a online measuring system based on machine vision is developed.The studies mainly on the following aspects:1.This paper introduced the machine vision technology,analyzed the online measurement system plan based on machine vision in detailed and built the hardware experimental platform;2.Camera calibration technology is researched.Calibration on the system through the experiment and credibility analysis of the calibration results has been done;3.By analyzing varieties of edge detection algorithm,a better first order edge detection operator which is more simple and faster is suggested.Using it,we can realize coarse position on edge.After this step,we refine edge using subpixel edge extraction algorithm in order to improve the edge location accuracy;4.The online measurement system software based on machine vision is developed.The software owns such features:modules complete,reliable performance,beautiful interface and easy operation,the software can be used as system working,system experiment,system demos and data processing; According to the software design,hardware installation and commissioning, the system errors produced in the rotating speed are measured and online measurement experiment is completed.The experimental data show that the syetem's measurement accuracy meet the measurement requirements.