The influence of virtual character actions and emotional expressions on trust in autonomous vehicles

Abstract With the rapid advancement of Autonomous Vehicle (AV) technology, improving user trust is critical to realizing its full potential. This study introduces a Virtual Character (VC) as an assistant for passengers, designed to enhance trust in AVs. The VC acts as an interactive guide, providing feedback and emotional cues to capture passengers’ attention during uncertain situations. To assess its impact on trust, Situation Awareness (SA), and acceptability, we integrated the VC into a Virtual Reality-simulated AV environment. Thirty-six participants experienced four conditions: a static VC, an emotion-only VC, an action-only VC, and a combined action–emotion VC. Results show that incorporating a VC can enhance user trust, SA, and acceptance of AV technologies. VC actions have a stronger effect on trust than emotional expressions, while emotional cues alone have the potential to reduce stress. Notably, participants preferred a VC that combines both action and emotion. These findings highlight the value of integrating expressive and behavior-rich VCs into AV interfaces to communicate system awareness, reduce uncertainty, and strengthen passenger trust.