When designing navigation systems, more attention should be paid to the way that motorists process information. Choosing clearer colours and symbols would make the systems easier to use. Older motorists in particular would then have more time to concentrate on the road, thus increasing safety. This has been revealed by research conducted by psychologist Ellen Wilschut. She will be awarded a PhD by the University of Groningen on 29 October.
More and more motorists are making use of navigation systems – the cost of the systems is falling and many more telephones are also equipped with navigation programmes. However, the call for legislation is getting louder now it appears that using navigation systems can lead to dangerous traffic situations. And quite right, too, as revealed by Ellen Wilschut’s research. A badly designed navigation system can delay the reaction time to information on the display by up to a second.
Crucial or irrelevant
Wilschut’s research concentrated on several aspects, including the complexity of what is displayed on the monitors of navigation systems. It turns out that information that is crucial to driving a car must be easy to differentiate visually from irrelevant items. The essential element should preferably only differ in one characteristic, for example colour or shape. The driver will then need relatively little time to look at the display and process the information and driving will improve as a result.
Senior citizens are slower
Senior citizens in particular turn out to have problems differentiating between different levels of information displayed on the monitor of a navigation system. EEG research revealed that test subjects between the ages of 50 and 70 are less able to suppress irrelevant information than those aged between 20 and 25. This turns out to affect the reaction time when driving – as revealed by an experiment in a driving simulator. When test subjects have to look at a complicated navigation system and then quickly react to the brake lights of the car in front, interference can occur – the brain cannot process all the information properly and the correct reaction (braking) is delayed. This effect was significantly stronger with older test subjects than with younger ones.
Design must improve
Manufacturers could contribute to traffic safety by paying more attention when designing navigation systems to the way that motorists process information. Wilschut: ‘In the design phase, a great deal of attention is paid to visual attractiveness, it seems. But an attractive display with lots of details and colours is not automatically better.’
Technological advances
Navigation systems should also take more account of the fact that road users sometimes have to react to unpredictable traffic situations. Wilschut: ‘In a city the chance that you have to react fast to the behaviour of other road users is much higher than on the motorway. Navigation systems should take such situations into account.’ In addition, there is a significant advantage in displaying navigation information on the windscreen instead of on a separate monitor on the dashboard, the research has revealed. The driver does not then have to shift his gaze but can switch between looking at the windscreen and through the windscreen. This would improve the driving performance of both older and younger drivers. However, further research needs to be conducted in this field.
Government guidelines
The government must force manufacturers to publish their research data, in Wilschut's opinion. ‘The car industry undoubtedly conducts research into navigation systems, but manufacturers are concerned about the results falling into the hands of competitors. This means that very little information is available.’ Governments should also set much clearer guidelines for navigation systems, the researcher feels. Wilschut: ‘From seatbelts to brakes, the EU has drawn up detailed specifications for all car parts. There are hardly any for navigation systems, despite the fact that using them can have major consequences for traffic safety.’
Curriculum vitae
Ellen Wilschut (Alkmaar, 1980) studied Psychology in Groningen and conducted her PhD research at the Leibniz-Institut für Arbeitsforschung of the Technische Universität Dortmund and the Department of Experimental Psychology of the University of Groningen. Her supervisors at the Faculty of Behavioural and Social Sciences were Prof. K.A. Brookhuis, Prof. M. Falkenstein and Dr A.A. Wijers. Wilschut is currently a researcher for TNO in Soesterberg. The title of her thesis is ‘The impact of in-vehicle information systems in simulated driving performance: effects of age, timing and display characteristics’.
Note for the press
Contact: Ellen Wilschut, 0346 - 356281, ellen.wilschut@tno.nl
