Robot apology as a post-accident trust-recovery control strategy in industrial human-robot interaction

© 2021 Due to safety requirements for Human-Robot Interaction (HRI), industrial robots have to meet high standards of safety requirements (ISO 10218). However, even if robots are incapable of causing serious physical harm, they still may influence people's mental and emotional wellbeing, as well as their trust, behaviour and performance in close collaboration. This work uses an HTC Vive Virtual Reality headset to study the potential of using robot control strategies to positively influence human post-accident behaviour. In the designed scenario, a virtual industrial robot first makes sudden unexpected movements, after which it either does or does not attempt to apologise for them. The results show that after the robot tries to communicate with the participants, the robot is reported to be less scary, more predictable and easier to work with. Furthermore, postural analysis shows that the participants who were the most affected by the robot's sudden movement recover 74% of their postural displacement within 60 s after the event if the robot apologised, and only 34% if it did not apologise. It is concluded, that apologies, which are commonly used as a trust-recovery strategy in social robotics, can positively influence people engaged with industrial robotics as well. Relevance to industry: Findings can be used as guidelines for designing robot behaviour and trust-recovery control strategies meant to speed up human recovery after a trust-violating event in industrial Human-Robot Interaction.