Briefly describe the application of machine vision in dimensional measurement and inspection

With the continuous development of manufacturing industry, the promotion and application of advanced manufacturing technology, automated manufacturing systems and advanced production models require advanced detection methods to adapt. As a result, machine vision technology began to appear frequently in the field of inspection in the manufacturing industry. The process of using a machine vision system to determine the deviation of a product relative to a set of standard requirements is often called machine vision inspection.  

machine vision systemIt has a measurement function that can automatically measure the appearance dimensions of the product, such as the measurement of outline, aperture, height, area and other dimensions. Dimensional measurement is an essential step both in the production process of products and in the quality inspection after product production, and machine vision has its unique technical advantages in dimensional measurement.

For example, this non-contact measurement method can avoid damage to the measured object and is suitable for situations where the measured object is inaccessible, such as high temperature, high pressure, fluid, environmental hazards, etc.; at the same time, the machine vision system can measure multiple sizes at the same time. Measurement realizes the rapid completion of measurement work and is suitable for online measurement; and the measurement of small sizes is the strength of the machine vision system. It can use high-power lenses to magnify the measured object, making the measurement accuracy reach above microns.

The size measurement of machine vision is based on the relative measurement method, and the actual size is calculated through traceability, magnification calibration, automatic edge lifting and screen image measurement. In precision measurement, the magnification is required to be 35* or more to obtain micron-level accuracy. At this time, the visual line width is less than 5mm. For measuring objects above 5mm, it is necessary to combine the shift analysis reading and the window measurement to complete.

For precise measurement of tiny sizes, machine vision systems are used to measure the diameter and number of tiny biological cells, to the size of tiny assembly gaps, to the dimensions of smaller mechanical parts and electronic products by installing high-magnification industrial lenses or microscope lenses. Machine vision systems are used in various fields.

Although there are many methods to achieve dimensional measurement, most of them are not highly repeatable, efficient and robust. Facts have shown that dimensional measurement based on machine vision technology has good continuity and high accuracy, which has greatly improved the real-time and accuracy of industrial online measurement. At the same time, production efficiency and product quality control have also been significantly improved.