Impact of dispositional and situational factors on willingness to use shared autonomous shuttles

The integration of shared autonomous shuttles (SASs) into existing transportation networks is crucial for fostering user acceptance. Optimizing public adoption of SASs requires public trust in their ability to provide safe, efficient, and effective transportation. While it is evident that trust is a key factor that influences adoption, certain inherent dispositional traits may moderate individuals' baseline trust and interact with situational factors to affect their willingness to adopt SASs. This study advances both the transportation technology acceptance and trust literature by using structural equation modeling (SEM) to identify key dispositional and situational factors that have an impact on individuals' trust in, attitudes towards, and intention to use SASs. Data was collected via online survey to adults residing in multiple cities within the United States of America and Australia. The results of the study confirm trust is a significant predictor of both attitude towards and intention to use SASs. The model also shows dispositional traits, such as the propensity to trust and the plasticity Big Five meta-trait (which consists of the openness and extroversion personality traits), significantly influence perceptions of and willingness to use SASs. Trust and plasticity had mediating effects that influence perceived risk and perceived usefulness - factors that in turn shaped both attitude towards and intention to use SASs. The results from this study are vital for informing strategies aimed at increasing acceptance and usage of SASs, ultimately contributing to the development of more effective and user-friendly autonomous mobility solutions.