Assisting the older driver - SWOV

Assisting the older driver
Functional limitations
Relevant design principles
General sensory deficits
Visual acuity
Colour vision
Night‐time visual acuity
Sensitivity to glare
Hearing
Contrast sensitivity and
motion perception
Selective attention
Perception‐reaction time
Hand dexterity and
strength
Use redundant cues, like auditory, visual and tactile feedback.
Increase character size of textual labels on traffic signs and invehicle
displays.
Use white colours on a black background for in‐vehicle
displays.
Use supplemental illumination for in‐car devices used in lowlight
conditions, retro reflective road signs, and fixed lighting
at intersections with high traffic or pedestrian volumes.
Use matt finishes for control panels and antiglare coating on
in‐vehicle displays, and reduce the intensity of traffics signals
during darkness.
Use auditory signals in the range of 1500‐2500 Hz range.
Where depth perception is important for information on invehicle
displays, provide non‐physical cues, such as relative
size, interposition, linear position and texture gradient. As
regards road design, use a minimum in‐service contrast level
of 3.0 for pavement markings, background plates to help
accentuate traffic lights, and a positive offset of opposing leftturn
lanes.
Enhance the conspicuousness of critical stimuli through
changes of size, contrast, colour or motion.
Give the user sufficient time to respond to a request by the invehicle
assistance system and provide advanced warnings to
provide the driver with enough time to react to the on‐coming
traffic situation. As regards road design, this can be
accomplished through multiple or advance traffic signs.
Use large diameter knobs, textured knob surfaces and controls
with low resistance.
Table 4. Functional limitations and relevant design principles for road design elements and
in‐vehicle displays (based on Caird et al., 1998, Gardner‐Bonneau & Gosbee, 1997, and
Staplin et al., 2001).
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