ISA Houston
HMI Design: The Goo Good, d, the th e bad, and the th e ugly (and (a nd wh at makes makes them so ) Standards Certification
Paul Gruhn, P.E.
Education & Training Publishing
ICS Triplex | Rockwell Automation
Conferences & Exhibits
Paul Paul Gruhn, Gruh n, P.E. P.E. – – – – – – – – –
Training Manager Manager,, ICS Triplex Triplex | Rockwell Rockwell Safety Systems Systems Specialist Specialist for for 22 years years e ow Member of ISA SP84 SP84 committee committee (20 years) years) Instructor for ISA’s ISA’s courses courses on Safety Safety Instrumented Systems (8 days of material) Co-author Co-auth or of ISA book on Safety Instrumented Systems Developer Develop er of commercial commercial modeling modeling software software Registered Registe red Professional Professional Enginee Engineerr in Texas ISA 84 Expert Expert
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ISA Houston
Why the con cern about HMIs?
People who don’t know b etter pro duce… Contrast : Things that are different should look very different. Repetition: Repeat visual elements Ali gn ment : Every element should have some visual connection with another. rox m y : Things that belong together should be placed together. Those that are different, should not. Source: The NonDesigners Design Book
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ISA Houston
Not following convention…
“Print” belongs under the “ ” .
Cancel!
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Situation Aw areness Three stages: 1. Being aware of the situation around you – Perception of needed data and the current situation
2. Understanding what the information means to you now – Comprehension of information and the current situation
3. Understanding what the information means to you in the future – Projection of future status Source: Designing For Situation Awareness
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Demon s of Situatio n Awareness • Attention tunneling – Fixating on one set of information to the
• Memory trap – Relying on limited short-term memory
• Workload, anxiety, fatigue and other stressors – Reduction of a person’s capacity to process
• Data overload – Overwhelming amounts of data
Source: Designing For Situation Awareness
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Demon s of Situatio n Awareness • Misplaced salience – Salience: the compellingness of certain – Being drawn to the wrong information
• Complexity creep – Too many features make it difficult to develop an accurate mental model
• Errant mental models – misinterpretation of information
• Out-of-the-loop syndrome – Automation can undermine SA
Source: Designing For Situation Awareness
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Where DCS graphics started…
Source: The High Performance HMI Handbook
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What we then mi grated to…
Source: The High Performance HMI Handbook
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Fewer color s, but is this r eally any diff erent?
Is this process healthy? What should the values be?
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So why have we develop ed thing s lik e this? • User had no internal standard or guideline • Vendor had no drawings other than P&IDs • Vendor understood what the control system was doing • Easiest solution was to display the PI&D with all the control system data • No one ever asked the operators what their goals were (not tasks!) • Few understand SA and its demons 12
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ISA Houston
Poor HMI design s h ave: • P&ID representation • No trends •
as ng sp nn ng grap cs
• Bright colors, 3-D shadows • Color coding of piping and vessel contents • Measurement units in large, bright text • Lots of crossing lines • Alarm related colors for non-alarm related elements • Inconsistent colors Source: The High Performance HMI Handbook
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The medical equivalent: Is thi s person OK? Temp
98.6 °F
98.0 – 99.5
B.R.
20 /min
16 – 24
Pulse
72 bpm
60 – 84
B.P.
120/80 mmHg >130 / >85
Col
197 mg/dL <200
HDL
52 mg/dL >40
LDL
126 mg/dL <130
Tri
100 Mg/dL <150 14
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ISA Houston
Is
this perso n
OK?
How far ahead of its time was this!! Source: The High Performance HMI Handbook 15
The Role of the Operator
Source: The High Performance HMI Handbook
• The human in the loop should be predictive, not reactive • The goal is to predict and prevent problems, not respond to them after they’ve happened 16
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Is this compressor runn ing optim ally?
What should the values be? Source: The High Performance HMI Handbook
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The compressor graphic i s superfluous!
Source: The High Performance HMI Handbook 18
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A g ood example: s tatu s, tr ends, an alarm…
Source: The High Performance HMI Handbook
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So what’s wr ong h ere?
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Is this compressor healthy?
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What should these values be?
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Good HMI design s h ave: • Depiction of process status and values as information, not numbers • model of the process (not a P&ID) • Key Performance Indicators as trends • No gratuitous information • Gray backgrounds, low contrast • Very limited use of color • Consistent visual and color coding • Gray process lines • Measurement units in low contrast lettering, if used at all Source: The High Performance HMI Handbook
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Change is difficul t • Are you riding the same mule, but just sitting in a different saddle? • “ , unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so.” Douglas Adams • Involvement and buy-in will be , technical staff, and operators
Source: The High Performance HMI Handbook
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For “ the rest of the story” … By Bill Hollifield , Dana Oliver, , Eddie Habibi For more info, visit: www.pas.com and www.mycontrolroom.com As well as the ASM consortium: www.asmconsortium.net
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For “ the rest of the story” … By Mica Endsley, Betty Bolté, &
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