Machine vision provides many capabilities such as presence verification, measurement, pattern recognition, barcode reading, optical character recognition, color match, print quality inspection, and surface inspection. Effective machine vision systems must not only capture a viable image, but must also interpret the image accurately to obtain meaningful information. Grantek can design and implement vision system solutions ranging from barcode readers to color cameras, and can even implement 3D cameras to determine three dimensions of your product.
Machine vision systems can perform complex analytical tasks generally assigned to humans, with the advantage that machine inspection takes place at the same high rate of speed as production. Humans are very good at qualitative analysis of a complex scene, but machine vision is very good at quantitative measurement of simple, structured scenes. A person cannot perform measurements at production speed or with the repeated accuracy of a machine vision system.
Incorporating vision systems improves quality and offers earlier defect correction, reducing rejections downstream after further investment into that product. The vision system’s computer evaluates captured images pixel by pixel. Because inspection takes place at production speeds, problems can be detected and in some cases corrected much more quickly.
Properly adding machine vision requires integration with other systems to achieve the desired result. The output of the vision system can be used as feedback for the process in order for active correction or to activate a reject gate. As the vision system inspects, it can react to and correct small discrepancies. For example, if it detects a small overfill, but not enough to reject, it can signal the system to meter the fill process to bring it back within optimum specifications, saving on material costs.
Machine vision can be used with new equipment or added to improve performance of existing machines and systems. Two main applications for vision systems are ID and tracking, and defect detection.
Serialization—ID and tracking
An advantage of Grantek’s turnkey system installations is our ability to integrate equipment at all levels: your vision systems can feed data to both the MES layer and your ERP system. When Grantek performs a turnkey project for a customer, we do extensive requirements gathering and feasibility studies to ensure we provide vision systems that will meet the customer’s requirements. We then engineer the solution, fabricate any additional materials needed, such as retrofitting older machines with cameras and sensors, procure and program the vision system components, and integrate them into the production line and on up the organization to the ERP level.
We also install label verification systems, an important aspect of pharma manufacturing which will become increasingly important to food and beverage manufacturers as the deadline for the Food Safety Modernization Act (FSMA) implementation approaches. We have experience with optical character recognition (OCR) and optical character verification to verify that the correct on-demand information is printed on labels, for example.
After the vision system installation, as part of our site acceptance test (SAT) we verify that all the labeling requirements are met. We troubleshoot and adjust as necessary to ensure optimal performance of the vision system within the scope of the project.
Defect detection is another primary application for vision systems. It may require more vision expertise than serialization/identification applications, because of the wide variety of things that may represent a defect—no two defect detection systems are alike. In most cases Grantek is asked by our customer to help them solve a problem, and we engineer a vision system solution accordingly.
Grantek has successfully designed and installed vision systems to perform defect checking on assembled products, such as counting the quantity of a product included in each package, and that the product is manufactured correctly before being packaged.
Lighting is very important in defect detection. Grantek’s vision system engineers have extensive expertise in specifying camera hardware and locating light sources to manage glare and shadows or provide omnidirectional lighting where appropriate.
As part of Grantek’s analysis and requirement specification process, we determine the most appropriate vision system application needed to meet customer requirements, whether an off-the-shelf solution for reading 2D barcodes or designing a custom defect detection system to automate rejection of product that does not meet visual inspection criteria. We can write software if needed to extract specific information from images as well as experience using the off-the-shelf tools provided by camera vendors.