Nut Machine Vision Inspection And Screening Studies And Design System

In recent years, with the ceaseless improvement of automation requirement in the industrialfields, machine vision inspection technology, as is a new type of technology, began to applying inmany fields, such as industrial, medical, remote sensing detection and intelligent traffic, etc.Among them, the products online detection is one of the most widely used in the machine visioninspection technology.Nut is a kind of mechanical parts which is widely used in the industrial fields. Especially insome fine production and processing fields, professional precision nut is often needed to use inproduction assembly. However, at present, a lot of nut manufacturer still use the traditionalmethods of artificial sampling inspection to control the quality of their products, which not onlyheavily depend on human, but also improve the enterprise cost. Moreover, because of theseparation of testing process and production process, it generates a very high missed detectionprobability. Therefore, in this paper, the nut detecting and screening system proposed based onmachine vision inspection technology has a very important application value to change thecurrent situation.Although, at present the appearance of the mechanical parts is more and more complicatedwith the increasingly diversified requirement of the industrial application, these complex shape ismostly composed by the linear and circular arc. Therefore, recognizing and detecting the featureof the straight line and circle is still the basis and the important content to detect these complexshape. Based on the study and reference of the related literature at home and abroad, this paperapplying the MATLAB image processing toolbox to the linear and circular features of the nut,using the improved Hough transform to extract the boundary and making dimensionalmeasurement to the corresponding geometric features, then epistatic machine according to themeasurement results to make parts quality decision results and through the serial port tocommunicate with MCU, at last the MCU control actuator movement and the completion of thescreening of parts.The main research contents, work, results include the following several aspects:1. According to the characteristics of the online detection and various parametersmeasurement of nut, this paper analyzes and studies the working principle and hardware structureof the on-line detection based on machine vision and screening system and make the relatedhardware selection;2. Put forward the specific process of nut on-line detection, including image acquisition andinformation processing, feature extraction and control and implementation;3. In image processing, this paper applies peak-valley method for the binarization processing; As to the nut inner hole circle extraction, this paper uses the random Hough transform algorithmto improve the system for circle detection speed and precision; Considering the characteristics ofparts to be detect in this system, as to extract linear feature, this paper uses the traditional Houghtransform algorithm to detect linear feature, which reduces the difficulty in developing the systemalgorithm;4. In the paper the system is calibrated. Moreover, the feasibility of the system softwarealgorithm is verified through the testing experiment on the hexagonal nut;5. The paper analyzes a variety of deviation which may be produced in the system and putforward the working assumption in next step;6. In the last chapter of the paper the system is tested and analyzed making use of theMATLAB platform. At last, in the appendix of the paper gives part of the relevant procedure.