As robots become a more central part of our daily lives, how we interact with them becomes increasingly important. Among humans, touch is well understood to be crucial to our emotional wellbeing, and being deprived of physical human contact has well-documented consequences. Is the touch of robots equally powerful?

That was the question posed by research from the Nara Institute of Science and Technology. The researchers tested the impact of robotic touch and also robotic touch when combined with speech on a pool of Japanese volunteers. For instance, sometimes the volunteers received a gentle stroke on their back from the robot’s arm, whereas in others they also received remarks such as “Hello, how are you doing?” alongside the stroke.

Making contact

After each experiment, the volunteers were asked to rate their mood as either positive or negative, while also reporting their level of emotional arousal. They also recorded how human they thought the robot they engaged with felt and had their muscle activity measured via both skin conductance and facial muscle activity.

The volunteers reported better mood in the conditions where the robot both touched them and talked to them. What’s more, they also said that their mood was most positively affected when the speech and touch happened simultaneously.

The results also found that there was considerably more facial activity in muscles associated with smiling when the robot touched and spoke to participants. People in this condition were also more inclined to think of their robot companion as human-like.

The researchers believe that their findings could be important in shaping the next phase of robot design, especially in fields where interaction with humans is so important, such as in elderly care, where robots have long been touted as an answer to skills shortages in the sector.