This type of interaction helps establish a social rapport between humans and machine, and shows that motor coordination is crucial to the interpersonal dynamics between the two. Published in January in IEEE Transactions on Autonomous Mental Development, the research brings us one step closer to communicating with robots in a natural and more sophisticated way.
Paying attention to human social behavior, the researchers replicated the concept in a human-robot scenario. They used a child-sized humanoid (a robot that resembles a human) equipped with a speech module that informed the 23 participants, 19 of which are staff and students from the university, of three gesture patterns to perform They could wave their hands in the shape of a circle, triangle, or infinity symbol.
Participants held a Wii Remote when performing the gestures. This allowed the robot to capture, record, and recognize the gestures so it could make appropriate reactions to the participants’ movements. The Wii Remote also has an optical sensor and an acceleration sensor, which helped increase the accuracy of the robot’s movements.
The robot had 18 degrees of freedom—or the number of independent pieces of information—that enabled it to mimic the person’s gesture patterns simultaneously. A synchrony detection system method, for example, was adopted that allowed the robot to respond in real time. This technique calculates the spatial and temporal relationships between the participant and robot’s movements. In the future, one can imagine this to mean that when people wave good-bye to the robot, it would wave back.
A majority of participants reported they preferred interacting with a robot that had motor coordination than without. Perhaps more surprisingly, human-robot motor coordination works both ways. The researchers said that previous studies in this area have shown that humans also adapt their behaviors to that of the robots when given the opportunity to interact with them, similar to how we change our voice and body language when we speak to kids or pets. (Just as long as we don’t start imitating robot dance moves.)