Investigating what level of visual information inspires trust in a user of a highly automated vehicle

• Published in: Applied ergonomics Vol. 90; p. 103272
• Main Authors: Ma, Rachel H.Y., Morris, Andrew, Herriotts, Paul, Birrell, Stewart
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2021
• Subjects: Autonomous vehicles; Driving simulator; HMI; Trust; Visual feedback; Driving simulator; Visual feedback; HMI; Trust; Autonomous vehicles
• ISSN: 0003-6870; 1872-9126
• DOI: 10.1016/j.apergo.2020.103272

The aim of this research is to investigate whether visual feedback alone can affect a driver's trust in an autonomous vehicle, and in particular, what level of feedback (no feedback vs. moderate feedback vs. high feedback) will evoke the appropriate level of trust. Before conducting the experiment, the Human Machine Interfaces (HMI) were piloted with two sets of six participants (before and after iterations), to ensure the meaning of the displays can be understood by all. A static driving simulator experiment was conducted with a sample of 30 participants (between 18 and 55). Participants completed two pre-study questionnaires to evaluate previous driving experience, and attitude to trust in automation. During the study, participants completed a trust questionnaire after each simulated scenario to assess their trust level in the autonomous vehicle and HMI displays, and on intention to use and acceptance. The participants were shown 10 different driving scenarios that lasted approximately 2 minutes each. Results indicated that the ‘high visual feedback’ group recorded the highest trust ratings, with this difference significantly higher than for the ‘no visual feedback’ group (U = .000; p = <0.001 < α) and the ‘moderate visual feedback’ group (U = .000; p = <0.001 < α). There is an upward inclination of trust in all groups due to familiarity to both the interfaces and driving simulator over time. Participants' trust level was also influenced by the driving scenario, with trust reducing in all displays during safety verses non-safety-critical situations. •Different levels of visual information were presented to three groups in a static driving simulator.•User subjective data on the level of trust in the autonomous vehicle was collected by questionnaires.•High visual feedback inspired a higher level of trust in the drivers compared to no and moderate visual feedback.•Users' trust level adjusts dependent on whether it is a safety or non-safety-critical situations.