A robot named Pepper at a convention in Lyon, France in 2015. / Photo by: Xavier Caré via Wikimedia Commons


Expression of emotional states is one trait known among humans and animals. In order to replicate this trait in robotics, scientists must be able to simulate associated reactions like skin changes. Scientists at Cornell University is presently working on a new robot design that involves the use of textural communication.

Expression of Emotional States among Robots

When humans and animals express emotions, there are specific changes that occur on the skin. These skin changes include goosebumps and hair standing on end. In robots, cloning the exact skin reaction can be done through the demonstration of textural expressions.

At Cornell University, scientists are developing textural communication in a new robotic design. The new robot uses an elastomer skin powered by pneumatics or pressurized air. The artificial skin has two texture modules, one on each side, which are intended to be gripped while interacting with it.

The texture modules have multiple texture units made of hollowed elastomers and are placed in a grid. The elastomers are attached to each other by internal channels that fill in the pressurized air, depending on the perceived stimuli. When air goes in, the texture units inflate and form a specific shape, either round domes or spikes.

If the robot interprets an emotion that causes goosebumps, the pressurized air fills in the round dome texture units. But if the robot understands something threatening, the air fills in the other texture units to form spikes, sending a message to others for them to “go away.” The spikey texture units cannot be flattened completely, but the pneumatic pressure can suck it back inside the elastomer.

According to the first author Yuhan Hu and co-author Professor Guy Hoffman, the next objective is to draft emotions properly to tactile expressions, and match the results with other known modalities, such as gestures and facial expressions.