PLCs & PACs / Systems Integration / HMI / SCADA

Beyond the Eyes

Process Control Applications Are Designed, Built and Operated by People With the Usual Eyeballs, Therefore They're Subject to Blinders Imposed on Sight

By Jim Montague

We rely too much on our eyes. I seem to remember that humans get 70% to 90% of their total sensory input through their peepers, which makes vision the most productive of the five senses. However, while eyes are an essential tool for practically all vertebrates, they can also become a crutch like any especially successful and prosperous device.

You know all the clichés. The hand is quicker than the eye. There's more to it than meets the eye. You can't see the forest for the trees. We know we're missing something.

So I'd bet the other senses don't magically become more sensitive or compensate when a person goes blind. Rather, without all the input from their eyes, people with impaired vision simply pay attention to their other senses that were there all along, but were drowned in all the visual input. Sound familiar?

Because process control applications are designed, built and operated by people with the usual eyeballs, they're subject to the same  blinders imposed on sight. Each flashy new PC, laptop, smartphone and tablet computer gives us yet another TV to stare at—and yet another chance for our minds to slip into the hazy, debilitating, low-Alpha-wave fog that the old boob tube has kept many of us in since childhood. Huh? What was I talking about? Precisely.

Each flashy new PC sceen gives us another TV to stare at—and another chance to slip into the old boob tube's hazy, debilitating, alpha-state fog.

– Jim Montague
In process control rooms and other places PC boxes were replaced by flatscreens, video walls and smart whiteboards—often without much thought about who uses them, or if they can work effectively and safely in that environment for years on end. It's old news now, but each leap in display hardware was accompanied by even faster advances in display software and graphics—to the point where the colorful pictures obscured important alerts and crucial alarms. Trees blocking the forest again.

Now, I know HMIs provide crucial information that couldn't be delivered any other way. Most do a fine job, and they will inevitably continue to be used. However, their users need to think about employing them more responsibly by valuing their own mind's attention span and capacity, prioritizing input sources and eliminating or suppressing as much chaff, blather, spam and other useless information as possible. 

So how can you restrict or focus vision and concentrate attention on what's important in the control room? Plan ahead. Don't just build a room, put up flatscreens, desks and chairs, and install HMI and SCADA software. Many contributors to this issue's "Smarter Reality" cover article say it's crucial to examine operator tasks, required measurements and indicators; identify present and needed functions; and build or renovate displays and control equipment around them as much as reasonably possible.

One of the best ways to do this in process control and automation is to learn and follow the guidelines of the Abnormal Situation Management Consortium (ASMC,, the Center for Operator Performance (COP, and similar international organizations. They stress focusing on what operators really need to know about what's happening in their applications, how to arrange displays for optimum, long-term operator alertness, and using colors and shapes in principled ways to improve situational awareness.

However, I'm still wondering if it's truly possible to perceive beyond our eyes? What's the true appearance of objects and the world without the perspective and limits imposed by the rods and cones on the retina at the back of our eyeballs? There are many examples of students using blindfolds to learn about the vision-impaired experience. Remember when Luke Skywalker first learned about the Force? Likewise,  a whole branch of Buddist practice involves blind archery. If you don't have a bow and arrow and don't want to imperil your neighbors, you can use a basketball, and try closed-eye free throws. You may be surprised by how many you can sink. And if we learn more about prioritizing sensory input in one exercise, it may help point out what's important in others.