cognitive ergonomics presentation

Design Analysis & Enhancement of Citroen C4 Dashboard and Displays

Lynne DoranHazel Kidney

Orla Shanahan

• “ The trend today is to produce automobiles that have exciting systems which enhance the users' driving experiences, however, the distraction potential of these systems has not fully been considered. “

(Tretten, Garling, & Pettersson, 2008)

Introduction to System

• Define boundaries – just the dashboard + displays

• Existing use scenarios/task

Problems Identified

• Colours and dials used

• Location of information –spread across 4 screens

• Warning Lights

Conceptualization of Problem – Colours and Dials

• Target signal similar to noise due to lack of colour or contrast -increase in false alarms and misses

• Lower contrast in both colour and size result in driver taking longer glances (Kim, Dey, Lee & Forlizzi, 2011).

• Displays are cluttered – self-terminating search(Wickens, 1999)

• Rockwell (1988) – when complex displays require glance durations beyond 2 seconds most drivers will experience visual workload problems.

Conceptualization of Problem – Colours and Dials

• Darker characters on light background – in contradiction to UMTRI design guidelines (Green, Levison, Paelke & Serafi, 1994).

• Tachometer –should increase in an upward motion not horizontally.

• Speedometer is digital – no congruence with mental model of speed (Wickens, 1999)

• No colour used in temperature or speed gauges

Conceptualization of Problem – Location of Information

Visual Search

• Four different screens• Dispersal of information and incorporation of

unnecessary information• The operator has to scan each screen, hindering

efficiency and increasing the time taken in visual search

• Serial Search• Target among stimuli model

Hazard lights

• Target Among Stimuli Model• Operator searched through various distracters for

hazard button• Parallel search; target defined using simple rule; as

experienced driver knew the hazard icon • Blocked field of vision due to

design of vehicle• Once attention was directed, signal was located

Signal Detection

• Target among stimuli• E.g. Kilometers traveled in a single trip

Warning Lights

Warning Signs Seatbelt control

Conceptualization of problems• Drivers must have their attention on the outside of

the car rather than on in-vehicle displays (Baber & Wankling, 1992).

• Signal detection

• Poor location – More important warning lights further from drivers view

• Symbols not obvious or clear

Poor Location

Positioned on the left Positioned on the right

Further from drivers viewpoint

How problems affect drivers

• All of these problems contribute to driver distraction, decreased situation awareness and increased mental load

• Drivers experience many distractions on the road, in vehicle distractions should be eliminated

Research Design

• Control and Display Survey – car owner, novice user

• Field Experiment: Novice user, completed tasks while drivingDependant Variable – Time taken to complete

task Testing attention levels

• “The dashboard does its primary job if it tells you with no more than a glance that you should act. It serves you superbly if it directly opens the door to any additional information that you need to take that action.”

Stephen Few

Proposed Solution

Proposed Solution

Proposed Solution

• Change colours – increase contrast and introduce pictorial realism

• Reduce clutter – simplify display• Move hazard lights• 3 screens –split HDD and HUD dashboard and

CS • Move information to more appropriate areas• Move warning lights

Solution for Colours and Dials

• Use of light characters on dark background (Green et al., 1994)

• Increase signal strength by using contrasting colours and sizes

• Pictorial realism – colour depicting danger on speedometer and temperature gauges

Solution for Colours and Dials

• Adheres to Nielson’s Heuristic Design Principles (1994)

• Clutter reduced – unnecessary elements eliminated

• Most commonly used instruments in a salient position

• System should now be self-evident

Solution for Colours and Dials

• Speedometer – keep digital numbers but include dial around outside – ecological compatibility

• Analogue tachometer

Solution for Location of info

• All important information displayed in HUD –speed, fuel gauge, engine temp

• Info in HDD – revs, warning lights• Radio, sat nav, heating, in CS – extras will be in

CS so changes will not distract driver • Reduces visual search• Improves signal detection

Solution for Screens• Improve visual search by reducing area

necessary for search – 3 screens, split dash (HUD, HDD & CF; Primary and secondary information)

• Change shape of screens improve UFOV

Solution for Warning LightsStudy by Tretten, Normark, & Gärling, (2008). • Warnings for serious failures and mechanical operation

preferred on the HUD.• Warnings for maintenance/service along with

reminders preferred on the HDD. • Response times and driving was perceived to be better

when using the HUD.

Signal Detection• Important warnings moved to HUD. • Can be detected by a sound.

Warning Lights Solution

• Urgent serious warnings = red

• Important warnings = orange.

• Icons with text labels are found to enhance performance, compared to icons alone.

• Enhance perceptions of usefulness, compared to text alone Wiedenbeck (1999)

Any Questions?

References• Baber, C. and Wankling, J. (1992). An experimental comparison of text and

symbols for in-car reconfigurable displays. Applied Ergonomics, 23(4), 255-262.

• Few, S. (2006). Information dashboard design: the effective visualcommunication of data. Publisher: O’Reilly.

• Nielsen, J. (1994). Ten usability heuristics. Retrieved fromhttp://www.useit.com/papers/heuristic/he uristic_list.html

• Regan, M. A., Lee, J. D. & Young, K. L. (eds.) (2008) Driver distraction: Theory, effects and mitigation. Florida, USA: CRC Press.

• Tretten, P., Normark, C.J., & Gärling, A. (2008). Warnings and Placement Positions in Automobiles. Luleå University of Technology.

References

• Wiedenbeck, S. (1999). The use of icons andlabels in an end user application program:An empirical study of learning andretention. Behaviour & InformationTechnology, 18(2), 68-82.