The utility of psychological measures in evaluating perceived usability of automated vehicle interfaces – A study with older adults. (July 2020)

• Record Type: Journal Article
• Authors: Voinescu, Alexandra; Morgan, Phillip L.; Alford, Chris; Caleb-Solly, Praminda
• Is Part Of: Transportation research. Volume 72(2020)
• Page Start: 244
• Page End: 263
• Publication Date: 2020-07
• Subjects: Usability -- Connected automated vehicles -- Fully automated driverless cars -- Human machine interface -- Older adults -- Individual differences; Automobile drivers -- Psychology -- Periodicals; Automobile driving -- Psychological aspects -- Periodicals; Transportation -- Psychological aspects -- Periodicals; 629.283019
• DOI: 10.1016/j.trf.2020.05.003
• Languages: English
• ISSNs: 1369-8478

Abstract

Highlights: Usability evaluation of a fully automated simulator-based human machine interface. Human machine interface designed and tested with older adults. Usability correlates positively with working memory and multi-tasking abilities. Increased trust in technology, low neuroticism anxiety correlate with usability. In car simulators high sense of presence, low simulator sickness boost usability. Abstract: The design of the traditional vehicle human-machine interfaces (HMIs) is undergoing major change as we move towards fully connected and automated vehicles (CAVs). Given the diversity of user requirements and preferences, it is vital for designers to gain a deeper understanding of any underlying factors that could impact usability. The current study employs a range of carefully selected psychological measures to investigate the relationship with self-report usability of an in-CAV HMI integrated into a fully automated Level 5 simulator, during simulated journeys. Twenty-five older adults (65-years+) participated and were exposed to four journeys in a virtual reality fully automated CAV simulator (with video recorded journeys) into which our HMI was integrated. Participants completed a range of scales and questionnaires, as well as computerized cognitive tests. Key measures were: perceived usability of the HMI, cognitive performance, personality, attitudes towards computers, trust in technology, simulator sickness, presence and emotion. HMI perceived usability correlated positively with cognitive performance (e.g., working memory) and some individual characteristics such as trust in technology and negatively with neuroticism anxiety. Simulator sickness was associated negatively with CAV HMI perceived usability. Positive emotions correlated positively with reported usability across all four journeys, while negative emotions were negatively associated with usability only in the case of the last two journeys. Increased sense of presence in the virtual CAV simulator was not associated with usability. Implications for design are critically discussed. Our research is highly relevant in the design of high-fully automated vehicle HMIs, particularly for older adults, and in informing policy-makers and automated mobility providers of how to improve older people's uptake of this technology.