Do I Sound as Capable as I Look? Impact of Robot Communication Style and Appearance on User Perception

Semantic-free utterances are thought to lower expectations of robot capabilities.However, to our knowledge, it still needs to be investigated how the type of robot communication (semantic-free utterance vs natural language), appearance (humanlike vs robotlike), and perceived voice-appearance alignment influence perceived robot capabilities.In a 2x2 online study, participants viewed videos with robots varying in communication and appearance.Linear mixed modelling showed that higher perceived voice-appearance alignment ratings were associated with higher perceived ratings of robot competency and agency.Contrary to expectations, semantic-free utterances and robot-like appearance were not significantly associated with perceived competency and agency.