Lasers, scanners, fingerprint readers, and face recognition is not just science fiction anymore. I love seeing technology only previously imagined become reality through necessity and advances in technology. We, as a world economy, need to be able to verify who we are and ensure transitions are safe, and material and goods are tracked accurately. With this need came the evolution of laser barcode readers, fingerprint identification devices, and face ID on your phone. Similar needs have pushed archaic devices to be replaced within factory automation for data collection.
When I began my career in control engineering the 1990s high tech tools were limited to PLCs, frequency drives, and HMIs. The quality inspection data these devices relied on was collected mostly through limit switches and proximity sensors. Machine vision was still in it’s expensive and “cute” stage. With the need for more information, seriously accurate measurement, machining specs, and speed; machine vision has evolved, just like our personal technology has, to fill the needs of the modern time.
Machine vision has worked its way into the automation world as a need to have rather than a nice to have. With the ability to stack several tools and validations on top of each other, within a fraction of a second scan we now have the data our era needs to stay competitive. Imagine an application requiring you to detect several material traits, measure the part, read a barcode for tracking, and validate a properly printed logo screened onto the finished product. Sure, you could use several individual laser sensors, barcode readers and possibly even a vision sensor all working in concert to achieve your goal. Or you could use a machine vision system to do all the above easily with room to grow.
I say all of this because there is still resistance in the market to move to machine vision due to historical high costs and complexity. Machine Vision is here to stay and ready for your applications today. Think of it this way. How capable would you think a business is they took out a carbon copy credit card machine to run a payment for you? Well, think of this before you start trying to solve applications with several sensors. Take advantage of the technology at your fingertips; don’t hold on to nostalgia.
Have you ever had to squint, strain, adjust your glasses, or just ask for someone with better vision to help read something for you? Now imagine having to adjust your eyesight 10 times a second. This is the power of machine vision. It can adjust, illuminate, filter, focus, read, and relay information that our eyes struggle with. Although the technology is 30 years old, machine vision is still in its early stages of adoption within the industrial space. In the past, machine vision was ‘nice to have’ but not really a ‘need to have’ technology because of costs, and the technology still not being refined. As traceability, human error proofing, and advanced applications grow more common, machine vision has found its rhythm within factory automation. It has evolved into a robust technology eager to solve advanced applications.
Take, for example, the accurate reading, validation, and logging of a date located on the concaved bottom of an aluminum can. Sometimes, nearly impossible to see with the human eye without some straining involved, it is completely necessary to ensure it is there to be able to sell the product. What would be your solution to ensuring the date stamp is there? Having the employee with the best eyes validate each can off the line? Using more ink and taking longer to print a larger code? Maybe adding a step by putting a black on white contrasting sticker on the bottom that could fall off? All of these would work but at what cost? A better solution is using a device easily capable of reading several cans a second even on a shiny, poor angled surface and saving a ton of unnecessary time and steps.
Machine vison is not magic; it is science. By combining high end image sensors, advanced algorithms, and trained vision specialists, an application like our aluminum can example can be solved in minutes and run forever, all while saving you time and money. In Figure 1 you can see the can’s code is lightly printed and overcome by any lighting due to hotspots from the angle of the can. In Figure 2 we have filtered out some of the glare, better defined the date through software, and validate the date is printed and correct.
Take a moment to imagine all the possibilities machine vision can open for your production process and the pain points it can alleviate. The technology is ready, are you?