Hiroshi Ishiguro

Enhancing synchronization among people when synchronization is lacking is believed to improve their social skills, learning processes, and proficiency in musical rhythmic development. Greater synchronization among people can be induced to improve the rhythmic interaction of a system with multiple dancing robots that dance to a drum beat. A series of experiments were conducted to examine the human–human synchrony between persons that participated in musical sessions with robots. In this study, we evaluated: (a) the effect of the number of robots on a subject’s ability to synchronize with an experimenter; (b) the effect of the type of robot synchrony, namely, whether the robots did or did not represent the subject’s rhythm; (c) the effect of an in-sync and out-of-sync robot on a subject’s behavior. We found that: (a) three robots increased the level of synchronization between the subject and experimenter and their enjoyment level; (b) robots may induce greater synchronization between the subject and experimenter by reproducing the rhythms of not only the experimenter but also of the subject compared to when only the experimenter’s rhythms had been reproduced; (c) the robots in-sync had greater influence on the natural rhythm of the subject.

This paper reports our research efforts on social robots that recognize interpersonal relationships. These investigations are carried out by observing group behaviors while the robot interacts with people. Our humanoid robot interacts with children by speaking and making various gestures. It identifies individual children by using a wireless tag system, which helps to promote interaction such as the robot calling a child by name. Accordingly, the robot is capable of interacting with many children, causing spontaneous group behavior from the children around it. Here, group behavior is associated with social relationships among the children themselves. For example, a child may be accompanied by his or her friends and then play together with them. We propose the hypothesis that our interactive robot prompts a child’s friends to accompany him or her; thus, we can estimate their friendship by simply observing their accompanying behaviors. We conducted a field experiment for two weeks in a Japanese elementary school to verify this hypothesis. In the experiment, two “Robovie” robots were placed where children could freely interact with them during recesses. As a result, we found that they mostly prompted friend-accompanying behavior. Moreover, we could estimate some of their friendly relationships, in particular among the children who often appeared around the robot. For example, we could estimate 5% of all friendships with 80% accuracy, and 15% of them with nearly 50% accuracy. Thus, this result basically supports our hypothesis on friendship estimation from an interactive humanoid robot. We believe that this ability to estimate human relationships is essential for robots to behave socially.