Examining the Impact of Robot Norm Violations on Participants’ Trust, Discomfort, Behaviour and Physiological Responses—A Mixed Method Approach

Abstract

As robots increasingly permeate diverse domains like healthcare, education, service industries and homes, accurately understanding humans’ responses to and behaviour towards robots is crucial. While many human-robot interaction (HRI) studies focus on either quantitative or qualitative approaches, we advocate a mixed-method approach. This study investigated robot norm violations by implementing a scenario where a mobile manipulator robot and a human, in-person, carry out a physical, competitive task. Sixty-two participants were recruited and randomly assigned to either an experimental or a control condition (balanced for age/gender). The scenario was a competitive scavenger hunt game where participants took turns with a robot. We investigated the robot behaviours’ effects on trust, discomfort, competence, enjoyment, participant behaviour and physiological changes. The mixed-method approach integrated physiological measurements, behavioural observations and qualitative responses, thus offering a comprehensive account of HRI dynamics in the context of norm violations. Questionnaire results reveal significant shifts in human perceptions and attitudes when social norms are violated by robots, compared to a norm-compliant control condition. Specifically, trust and enjoyment decrease, discomfort increases and the robot’s perceived competence is compromised. These findings are extended through additional analyses of participants’ physiological changes, behaviours and responses to open-ended questions. Behavioural observations indicated increased verbal engagement and emotional responses, while physiological data showed elevated stress levels in the experimental group. Our study highlights the advantage of a mixed-methods approach combining different qualitative and quantitative data, providing a more comprehensive picture of participants’ perceptions of a robot, and how they react and respond to robot norm violations.