Robots as Hosts in Autonomous Buses

Abstract

In Autonomous Public Transport (APT), particularly with shuttle buses, passengers travel in smaller, more intimate vehicles—and in the future, such vehicles may operate without an authoritative driver or host. This setup may lead to potential safety concerns, as passengers are left alone together. Additionally, this future absence of a driver or host means that there is no one to address questions or uncertainties that may arise. One proposed solution is introducing a robot onboard the bus, serving a similar role to a human host. To explore this solution, an experiment was conducted in Barkarby, Stockholm, Sweden. Passengers, generally unfamiliar with APT or social robots, experienced two short rides on a bus equipped with either an embodied Furhat robot as the host or a disembodied voice agent in the ceiling. Data were collected from passenger-agent interactions, post-questionnaires, and semi-structured focus group interviews. Results indicate a division in passenger preferences, with some favoring the robot and others the voice assistant. Passengers asked more questions to the robot, suggesting a clearer affordance for interaction. While the questionnaires did not show significant differences, passenger behaviors indicated that they anthropomorphized the robot more. The interviews revealed that passengers felt more secure with a human operator and doubted the robot’s authority during incidents with aggressive passengers or accidents. Our findings show that social robots can help make autonomous buses feel more welcoming and interactive. Future APT systems have many design issues that need to be resolved before riders can find them safe and appropriate to use, and social robots can play a role in resolving such issues—both the ones we see today, and potentially ones that will appear in the future.