IE 366 Chapter 16 Displays

IE 366 Human-Machine System Displays Controls Other Subsystems Environment Human(s)

IE 366 MD-11 Cockpit Copyright  Harri Koskinen, used with permission, downloaded from 30 Jun 04

IE 366 Functions of Dynamic Visual Displays ● Continuous System Control – steering (vehicle control) – tracking ● state variable  target value ● System Status Monitoring – quantitative (state information) ● levels (quantities) ● rates – qualitative (status)

IE 366 Functions of Dynamic Visual Displays (2) ● Briefing – mission plans – procedures ● Search and Identification – surveillance ● Decision Making – alternative identification, selection – planning – diagnosis – extrapolation

IE 366 Visual Display Technology ● Mechanical (often electromechanical) – fixed/moving pointer, moving/fixed scale – counters (e.g., odometers) – flags ● Electronic – lights (incandescent, nixie tubes) – light emitting diodes (LEDs) – cathode ray tubes (CRTs) – liquid crystal displays (LCDs) – other flat panel displays ● Optical Projection – projectors ● front projection ● back projection – head-up displays (HUDs) – head/helmet mounted displays (HMDs)

IE 366 Visual Displays OIL FUEL Circular Analog Linear Analog Annunciators Digital (Counter)

IE 366 General Display Principles ● Color ● Coding ● Approximation

IE 366 Color ● Advantages – aesthetic appeal (user-preferred) – opportunity for color coding – superior performance (in some cases) ● Disadvantages – technological limitation, cost – non-superior performance (in other cases)

IE 366 Coding ● Color – < 9 discriminable colors (absolute discrimination) ● normal ● caution ● warning – < ? (relative discrimination) ● Shape – alphanumeric: < 82 (A-Z, a-z, 0-9, <, (, +, &, …) – geometric: < 15 – pictorial: < ?

IE 366 Coding (2) ● Magnitude < 7 (± 2) – area – line length – number of primitives – luminance – stereoscopic depth – inclination

IE 366 Approximation ● Definition – Get attention with one display – Present detailed info with another ● Example – Red oil pressure annunciator near LOS – Oil pressure gauge elsewhere

IE Principles of Display Design (Wickens, Gordon, & Liu) ● Perceptual Principles ● Mental Model Principles ● Principles Based on Attention ● Memory Principles

IE 366 Perceptual Principles 1. Avoid absolute judgments – absolute vs. relative judgment 2. Top-down processing – people observe what they expect to observe 3. Redundancy gain – alternative stimulus attributes 4. Discriminability – similarity causes confusion

IE 366 Mental Model Principles 5. Pictorial realism – looks like what it represents 6. Principle of the moving part – compatible with user’s mental model of motion 7. Ecological interface design – close correspondence with environment being displayed

IE 366 Principles Based on Attention 8. Minimizing information access costs important or frequently accessed info is easy to access 9. Proximity compatibility principle close to what it represents close to its control 10. Principle of multiple resources auditory vs. visual spatial vs. verbal (perceptual/cognitive vs. response)

IE 366 Memory Principles 11. Principle of predictive aiding – predictive display = proactive user 12. Principle of knowledge in the world – don’t overburden human memory 13. Principle of consistency – be consistent

IE 366 Applications

IE 366 Two-Valued Information (Warning and Alert Information) ● Examples – Low oil pressure indicator (automobile) – Door open indicator (aircraft) ● Types – Lights – Flags ● Technologies – Electronic – Mechanical

IE 366 Two-Valued Information (2) ● Principles – Should attract attention of busy or bored operator. – Should tell what is wrong. – Should not prevent continued attention to other duties. – Should not be likely to fail. – Should not give false alarms.

IE 366 Quantitative Information (Exact Reading) ● Examples – Oil pressure (psi) – Speed (mph) – Temperature (deg) ● Types – Counter – Digital display ● Technologies – Electronic (LED, LCD, CRT, …) – Mechanical (drum, disk, …)

IE 366 Quantitative Information 1 (cont’) ● Principles – Mount close to panel front to minimize shadows, etc. – < 2 changes/second – 1 : 1 height-to-width ratio – 1/4 - 1/2 width spacing – high contrast

IE 366 Quantitative Information ( Approximate to Exact Reading plus Rate Info) ● Examples – Altitude (aircraft) – Speed (auto, aircraft) – Temperature (chemical reactor) ● Types – Fixed scale moving pointer – Fixed pointer moving scale ● Technologies – mechanical, electromechanical – electronic (CRT, LCD, …)

IE 366 Fixed Scale Moving Pointer (1)

IE 366 Fixed Scale Moving Pointer (2)

IE 366 Fixed Pointer Moving Scale (1)

IE 366 Fixed Pointer Moving Scale (2)

IE 366 Quantitative Information (2) ● Principles – Scale range – Interval values – Scale layout – Pointers – Motion

IE 366 Scale Range ● Select least precise scale that meets operator’s needs. ● Display in immediately usable form, e.g. +0% - 110% maximum RPM rather than RPM

IE 366 Scale Intervals Good progressions (0.1 unit numbered interval) (1 unit) (5 units) Fair progressions (0.2 unit) (2 units) Poor progressions (0.25 units) (4 units) (2 units, poor initial point)

IE 366 Scale Layout ● Circular – Numbers increase clockwise – Zero break – Zero at bottom (positive scale) – Zero at 9 o’clock position (positive - negative scale) – Numbers inside graduation marks

IE 366 Circular Display

IE 366 Positive/Negative Display

IE 366 Linear Displays

IE 366 Linear Displays (2)

IE 366 Pointers ● To but not over minor scale markings ● As close to surface as possible (parallax) ● Same color as dial markings ● Pointer tip angle  20 degrees

IE 366 Long-Scale Displays: Multiple Pointer

IE 366 Long-Scale Displays: Pointer/Counter

IE 366 Motion (Fixed Pointer Moving Scale) ● Scale numbers increase in clockwise direction ● Compatible control / scale movement ● Clockwise control movement increases value ● Avoid FPMS displays (inconsistency)

IE 366 FPMS Anomalies (1)

IE 366 FPMS Anomalies (2)

IE 366 Check Reading ● Examples – RPM ok? – Temperature ok? ● Types – FSMP – FPMS ● Technologies – Mechanical – Electronic (CRT, LCD, …)

IE 366 Check Reading (2)

IE 366 Check Reading (3) ABCD

IE 366 Complex Displays

IE 366 Pictorial Display (System Synoptic)

IE 366 Horizontal Situation Indicator (HSI)

IE 366 Moving Map Display Garmin MX20 general aviation multifunction display, last accessed 22 Feb 08

IE 366 Pathway in the Sky Display A REVIEW OF PATHWAY-IN-THE-SKY DISPLAYS, Dick Newman, FAA, last accessed 22 Feb 08

IE 366 Head-Up Display windscreen mirror projector pilot’s eye combiner HUD image (at optical infinity)

IE 366 Head-Up Display Source:

IE 366 Military Aircraft HUD

IE 366 Head Mounted Displays Virtual Realities, last accessed 22 Feb 08http://

IE 366 Helmet Mounted Display VSI F-35 HMDS - Joint Strike Fighter Helmet Mounted Display System hmcs.com/pages_hmcs/03b_f35nite.htmlhttp:// hmcs.com/pages_hmcs/03b_f35nite.html, last accessed 22 Oct 07.