Hastie, Professor HelenRajendran, Professor GnanathusharanRomeo, Doctor MartaNesset, Birthe2026-01-272025-07https://www.ros.hw.ac.uk/handle/10399/5277With the increasing integration of robots into social and industrial domains such as healthcare and manufacturing, understanding how trust is built, maintained, and repaired in the face of system failures becomes crucial to ensure the long-term effectiveness and acceptance of autonomous systems. This thesis aims to contribute to the research field of Human-Robot Interactions (HRI) by investigating different aspects of trust in the face of robot failures and repair attempts. To do so, five separate studies were conducted. First, the thesis evaluates different trust measures to ensure that the correct tools are used throughout the thesis and to provide recommendations for other researchers. Then, two studies investigate repeated failures and repair strategies through the implementation of a communication incongruence performed by both a robot and a human actor. Finally, the last two studies examine humans’ attitudes towards artificial “trust” and investigate if trust in HRI can be transactional. The work presented in this thesis consists of both qualitative and quantitative findings, all contributing to a better understanding of how trust in HRI can be impacted by failures. Key findings in this thesis include guidance on trust repair in the face of repeated failures, a trust scale comparison, and reflections and recommendations surrounding artificial “trust” implementation.enThesis