Influence of age on the communication design of automated vehicles with pedestrians - a comparison between persons in middle and older adulthood

Kurzfassung

The introduction of automated vehicles (AVs) into road traffic brings with it a variety of changes. While in conventional road traffic the drivers communicate with their traffic environment, this task will be taken over by the AV in the future. To this end, various external human machine interfaces (eHMI) have been developed and evaluated in the past. It has already been shown that eHMIs can have a positive influence on the emotions experienced, the subjective perception of safety, the willingness to cross and the decisionmaking reliability of pedestrians when crossing the street. Previous studies have been conducted predominantly with middle-aged individuals without physical and/or mental limitations. However, due to the natural aging process, cognitive, neural, and visual impairments, become apparent from the age of about 50 years onwards, which may influence the perception of vehicles and participation in road traffic. This paper will use a pedestrianAV interaction to consider possible effects of older age on interaction with an AV. To do so, two studies on eHMI communication concepts are replicated using a stratified sample consisting of 50-64-year olds and 65-74-year olds. Study one investigated the influence of an eHMI on the experienced subjective safety, the perceived quality of information, and on affective valence, arousal, and dominance in a 1:1 scenario in interaction with a car or bus, using a total of N = 128 subjects (mean age: 63.70). The result of the study is that especially the dynamic eHMI has a positive influence on the perception of safety, the experienced emotions and the perceived quality of information. The car is generally perceived as less threatening than the bus. No differences were found between the age groups. Following on from study one, study two investigated the influence of an eHMI on the willingness to cross and decision reliability in more complex scenarios. Using N = 103 subjects (mean age: 62.87), it was shown that the dynamic eHMI significantly increased willingness to cross. The presence of multiple VTs had a negative effect on decision confidence. Differences between the age groups could not be found.