by Andy Wilson
There's an old joke about a boy riding his bicycle around his house with no hands on the handlebars shouting, "Look Ma, no hands." He goes around the house again and—without feet on the pedals—calls, "Look Ma, no feet." After a third trip, without hands on the handlebars or feet on the pedals, he exclaims, "Look Ma, no hands, no feet." After a few seconds, there is a loud noise. He approaches his mother with the sorry statement, "Look, Ma, no teeth." Even when I first heard this trite joke, I did not find it funny, especially with my dental bills.
Now it seems that a similar joke is being pulled on engineering managers at manufacturing organizations. These engineering managers often possess highly specialized manufacturing skills, but they may not include computer science, optics, machine vision, or image processing. However, they have one thing in common—serious manufacturing and engineering issues that must be resolved. They understand that the manual inspection of small parts generally, in the long term, proves cost-ineffective and labor- and time-intensive and that such processes should be automated with a machine-vision system.
This, unfortunately, is where the machine-vision industry joke begins. After reading marketing-type articles in technical publications and journals, such engineering managers may be fooled into thinking that machine-vision systems are becoming true plug-and-play application opportunities.
Plug and play?
With the advent of smart cameras, end-user-targeted machine-vision software, low-cost frame grabbers, and associated hardware, many OEM vendors are labeling their products with "no programming required" tags. To promote this pseudoconcept, several vendors offer smart cameras with embedded software, processing, and networking capabilities. But I have yet to see one smart camera—with the exception of those that use neural networks—that does not require programming. Whereas many vendors do provide competent machine-vision solutions, they are not true "plug-and-play" solutions. I call this the "Look, Ma, no programming" scenario.
The second part of the industry joke occurs after the systems integrator or engineering manager has purchased the machine-vision solution. I call this the "Look Ma, no engineering" scenario. Once purchased, machine-vision systems must be installed. The second part of the industry joke is also humorous. It begins with a story about how easy it is to install a machine-vision system once you have purchased a "solution."
Generally, this includes a great deal of misinformation that may include, but is not limited to, decrying real-time operating systems as "unnecessary," specifying resolution in terms of how many resolvable pixels the sensor has, touting nondeterministic networking standards as "industry saviors," and, my favorite, promoting CMOS-based sensors as having equivalent or better performance than that of CCDs.
Rather than quantitatively calculating the lighting, lenses, cameras, networking, and processing requirements needed (that is, engineering) to solve a particular application problem, one vendor suggests "it's easy; you just wave a piece of cardboard in front of a cameras until you obtain an image." If no such image appears, or the product is moving down the production line too quickly, adds the vendor, "play around with the aperture of the camera's lens" until you obtain the correct image. If all this fails, add some strobe lighting. That'll fix it.
I claim that observing "no programming required" and "no engineering" needed, you'll quickly fall off your bicycle. More important, "Look, no programming, no engineering" results in a "no working" system. Just as the boy on the bicycle might face thousands of dollars of dental bills, you will be faced with thousands of dollars in product cost and engineering fees just to make the system you originally purchased operate in a satisfactory way. As a result, you'll probably face an angry boss questioning your skills about how a computer-based machine-vision control system could be installed without engineering expertise. And if he gets really angry, you may be saying, "Look Ma, no job."