Human Centered Design in Operator Displays

Emerson’s Juan Carlos Bravo highlights the human centered design improvements in the DeltaV version 11 release. His focus in this 5-minute YouTube video is on the DeltaV operator displays.

Much of the design comes from the research conducted with the Center for Operator Performance and the Emerson Human Centered Design Institute. I summarized some of this research in posts such as Operator Display Color Usage Study, Color Considerations in Alarm Design, Avoiding Abnormal Situations with Better Alarm Management, and Center for Operator Performance Seeks to Improve Operator Effectiveness.

In the video, Juan Carlos shows the results of the application of the research findings. At the 0:35 mark, he shows a common way operator graphics were designed with lots of colors and fancy 3D shapes. At 0:58, he shows the issues with the school of thought around grayscale graphics. It’s like switching from your color TV back to black & white TV.

The other issue Juan Carlos highlights is that typically process variables (PVs) were presented on operator graphics without the context of deviations, location in range, proximity to alarm limits, etc. The HCD research found that operators respond more effectively to patterns, shapes, forms, and trends. At 1:45, Juan Carlos shows four palettes of colors or themes that help avoid the issues operators had with grayscale graphic.

DeltaV-Pressure-Control-Display.JPGAt 2:15, he shows additional templates that were added to provide more visual context than simple PV display. For example, a pressure control loop display shows an operating range bar with a bar showing the current PV, the visual location of the setpoint, and percent in range.

The intent of these simple visuals is to allow operators to scan the displays to quickly spot patterns of abnormalities. The faster abnormal situations can be identified, the great the chance that operator can take action to avoid unplanned shutdowns, equipment failures, or other potential consequences.

With the recognition that experienced operators are retiring at an increasing rate in some world areas, Juan Carlos shows at 2:45 how the labels on the operator displays can be changed to show more friendly names. This helps inexperienced operators learn the process. For example, instead of showing PC701_02 for the distillation column pressure controller, the friendly name might be “Pressure Control”.

One final item I’ll highlight from the video is contextual alarm knowledge. At 3:15, Juan Carlos shows how additional information can be provided with the help button for a given alarm. His example shows an estimated time to respond, how long the alarm has been active, and the consequences of inaction. Recommended actions can be provided along with probable causes and design information associated with the control loop. Juan shares several different ways to populate this knowledge at 3:40. Also, a search tool was added to help locate things more quickly.

Operator performance is a large area for human centered design improvement. Converting the research into software for the operator can help reduce the time that abnormal situations are spotted and addressed.

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