Operator Interfaces Expand Human Factors

Changes definitely are afoot with operator interfaces. Their definition broadens. And certainly, human factors’ role increases in interface improvement.

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“Typically, when people talk about operator interfaces, they talk about the schematic display the operators use to control and monitor the process,” says Peter Bullemer, senior partner with consulting firm Human Centered Solutions LLP (www.applyhcs.com), in Bloomington, Minn. “But the broader interface needs to be advanced.” That broader view includes not just the operator’s console, keyboard and display screen(s), but also the entire control room and co-workers. It also includes connection to plant business systems via personal computer (PC), connection to field operators via mobile communications, and other links.

One of the past decade’s trends is less face-to-face contact between field and control-room operators, says Bullemer, co-founder and former director of the Honeywell-led Abnormal Situation Management Consortium (ASM, www.asmconsortium.com). He says mobile tools can help bridge that gap. For example, “for field operators, there’s an advantage in performing their tasks through effectively uploading information directly to a database to which the control-room operator has access.”

Better connectivity may include using radios, adds Chris Stearns, operator and maintenance effective marketing manager with automation vendor Honeywell Process Solutions (hpsweb.honeywell.com), Phoenix. “Also with tablet PCs or handhelds, you can actually represent the actual process in the field.” Bullemer adds that some companies explore videoconferencing to “review issues [with staff] that need to be done during the shift.”

What Bullemer also sees is new awareness of human factors in design of operator interfaces. That includes “ergonomics of control rooms, to situational awareness of the displays that operators are using,” he says.

Part of that ergonomics evaluation includes whether or not the display fills the entire monitor. “In the old days, if I was going to create a display, it would be 17-by-20 inches, the only choice I had,” says David Strobhar, chief human-factors engineer at Dayton, Ohio-based Belville Engineering Inc., which provides human factors engineering resources. “But with the [Microsoft] Windows environment, I can choose any size, including pop-ups.” He cites Nova Chemical, in Toronto, Canada, which now extensively uses pop-ups, activated by operator preference, for non-critical information.

Something else Strohbar notices is the concept of how many monitors an operator can manage or needs. Calling 20-inch monitors “small now,” he says some companies have gone to 30-inch monitors, with “a lot of control rooms going to 42-inch ones.”

Domain-specific design

But what is presented on any monitor may be too busy. “Maybe a flaw in the approach that we’ve taken in building displays for operators is that we’ve taken engineering drawings and mimicked them on the displays, without full interaction requirements of information needed and what to do,” Bullemer suggests. What is one way to address the situational awareness? Do up-front analysis of what decisions operators need to make and then what needs to be done, he says. “And not at a generic level, but at a domain-specific level, which will be different for every operator.”

Yet another trend Strohbar sees now concerns the design of the operator’s console. “The current design is almost an extension of a workbench: just like your desk, a large lay-down area with a monitor in back.” But what he observes is that everything done on the screen is now done with just a numeric keypad, not a keyboard. “So, maybe the desk paradigm for the work station with a desk is no longer useful.”

What is, though? “I could see something more like a sit/stand operation, desks that move up and down,” says Strobar, who is also affiliated with the Center for Operator Performance (www.operatorperformance.org), Dayton, Ohio. “The operator would not be locked into a standard office chair.”

Still, Stearns reiterates that standard human aspects—such as sitting at appropriate heights—cannot be ignored. “It’s all human factors.”

C. Kenna Amos, ckamosjr@earthlink.net, is an Automation World Contributing Editor.

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