What factors affect the accuracy of machine vision inspection equipment? How to maintain?

Date：2021-12-23 11:05:22Views：909

Machine vision is an interdisciplinary subject involving artificial intelligence, neurobiology, psychophysics, computer science, image processing, pattern recognition and many other fields. Machine vision mainly uses computer to simulate human visual function, extract information from the image of objective things, process and understand it, and finally use it for actual detection, measurement and control. For example, in the automatic manufacturing industry, using machine vision to measure and detect various dimensional parameters of workpieces, such as length measurement, circle measurement, angle measurement, arc measurement and area measurement, can not only obtain the dimensional parameters of online products, but also make online real-time judgment and sorting of products, which is widely used.

The detection system based on machine vision technology has the advantages of low cost, high precision and easy installation. In addition, the powerful visual software is easy to adjust, flexible and convenient, and the measurement data can be stored, which is convenient for establishing statistical analysis, quickly discovering and solving problems. It is the best choice for Industry detection technology.

However, in some machine vision inspection projects, many customers encounter the problem of detection accuracy. For example, the overall dimension and internal and external diameter of machined parts shall be tested, and the accuracy shall be up to 10um. At present, many configurations choose 5 million cameras, which can theoretically achieve an accuracy of 10um. But the accuracy of the actual customer test is far from meeting the requirements of 10um. It's good to be able to do 30um. The main reasons for large errors are as follows:

1. Selection of industrial cameras:Many customers choose CMOS cameras for cost consideration. When photographing the edge of an object, the contrast of its edge contour is poor and the noise is large, which brings large errors to the software measurement. CCD chip camera is usually recommended.

2. Camera lens selection:Due to the height difference of many mechanical parts, there is a large depth of field. Because of the angle of view of ordinary lens, it is difficult to capture the inner wall of parts and components, which makes it difficult to find the most real and accurate edge contour in software processing, and puts forward higher requirements for image processing algorithm.

3. Selection of light source:Many customers will choose ordinary backlight. When the visual detection accuracy is not high, the backlight has the advantage of price. On the premise of high requirements, the principle of the backlight is to use light to produce uniform and soft light through the diffuse reflector, and the light generated at a certain point will diverge to any angle in the space. When detecting circular and cylindrical objects, diffraction will occur at the edge of the measured object. At the same time, the brightness of the light source also has a great impact on the brightness and darkness of the image.

In daily work,How should visual inspection equipment be maintained？

No matter what kind of machinery and equipment, it is necessary to maintain the equipment in order to make it work normally and work better for us. To maintain the equipment well, do the following:

1. Regularly check the wear of vulnerable parts and sliding blocks, and whether it is necessary to adjust their clearance or replace them with new parts.

2. Regularly fill the transmission parts and bearings with lubricating oil to avoid damage due to lack of oil.

3. Three point combination: discharge water once a day; Special lubricating oil shall be added to the air lubricator regularly; The filter screen of the air filter shall be changed and washed once a week.

4. Regularly check the contact of electrical lines, whether the wires are broken and aging, and clean the dust and sundries in the electrical box.

Do these things well, your machine vision detection equipment can better bring benefits to you, and the service life of the equipment can be maintained or even extended normally. Our company's testing services cover: electronic component testing and verification, IC true and false identification, product design and material selection, failure analysis, function testing, factory incoming material inspection, tape braiding and other testing items. Welcome to call Chuangxin testing, we will serve you wholeheartedly.