An experimental investigation of interference effects in human-humanoid interaction games

Investigating how people respond to and relate to robots is a multifaceted scientific challenge. This paper reports on an experimental investigation concerning movement interference effects between a human and a robot. We compare results with that obtained by Oztop et al. [1], however, in our study we used a small child-sized robot (KASPAR) with an overall human-like appearance. The experiment was conducted with both child and adult participants who interacted with a small humanoid robot using arm waving behaviours. The experimental setup was designed to be less constrained than in [1] with an emphasis on playful interaction. The experimental results did not show evidence for interference effects. This might be due to a more game-like and less constrained experimental environment or to the specific features of the robot or both. In addition to measurements of the variance of the movements, we investigated a measure for behavioural synchrony between human and robot movements based on the concept of information distance. The results of information distance analysis indicated that most of the human participants were affected by the robot's behavioural rhythms. While our experiments did not show a movement interference effect, we found behavioural adaptation of participants' movement timing to the robot's movements. Thus, the measure of behavioural synchrony that we introduced appears useful for complementing other measures (such as variance) previously used in the literature.