When asked to think of a humanoid robot, it’s very likely that you are imagining the robots featured in the TV show Westworld or the movie Ex Machina: robots that are human-like but not actually human. These images mostly stem from sci-fi, but the real world isn’t too far from producing robots of this kind. In recent years, humanoid robots have visually become increasingly similar to real humans. One of the most obvious aesthetic differences from the metallic robots envisioned in the past is addition of human-like skin that covers these robots. While the addition of this skin is purposed to create a more human-like appearance for humanoids, it has caused mixed responses in the growing human-robot interaction field.
Meet Sophia, the artificially intelligent humanoid robot that has redefined what it means to be a human-like robot (Figure 1) . Created in 2014 by Hanson Robotics, based in Hong Kong, Sophia is one of the most advanced artificially intelligent cyborgs ever made. She can hold simple conversation, imitate human gestures, and perform facial and voice recognition. Her features are aimed to make her a social robot that can interact naturally with other humans, potentially for future uses in customer service, psychological therapy, and elder care. Aside from the many tasks that Sophia can perform, the first thing that one might notice about Sophia is her appearance. Sophia’s face is covered in a patented material called “Frubber”, or “flesh rubber” . This “skin” simulates real human skin and, in Sophia’s case, was designed to resemble the visage of Audrey Hepburn. “Frubber” allows Sophia to portray over 50 different facial expressions, giving her a sense of possessing true human-like qualities.
Despite these efforts to make Sophia as “human” as possible, people who encounter her oftentimes experience a complex emotional response, rather than a sense of comfortable familiarity. Many journalists describe Sophia as “creepy” and impersonal, which are not exactly character traits that a social robot would desire. But why is it that people describe feelings of discomfort and, in severe cases, repulsion towards robots such as Sophia? Decades ago, a robotics professor at the Tokyo Institute of Technology named Masahiro Mori published an essay describing this exact phenomenon, now known as the uncanny valley effect (Figure 2). He proposed that “a person’s response to a human-like robot would abruptly shift from empathy to revulsion as it approached, but failed to attain, a lifelike appearance” . In other words, as an object moves closer to becoming 100% human (left to right on the graph), feelings of familiarity increase until a point in which the object becomes discomforting to look at . The phenomenon of increased familiarity and great discomfort are augmented with moving objects (dotted line) in comparison to objects that remain still (solid line). In the case of Sophia, though her skin and facial expressions are designed to make her appear more human-like, she isn’t quite human. Her human-like characteristics make her fall within the valley for most people, making the majority of people unable to comfortably interact with her. Two of the most well-studied drivers of the uncanny valley are atypicality (having features that are unusual for an object) and category ambiguity (having difficulty in characterizing an object) . However, the underlying psychological processes that drive the uncanny valley effect are still unknown. Based on current studies, the future of human-robot interactions may depend on designing robots that can cross the uncanny valley.
Will there be a point at which advancements in artificial intelligence are combined with a human-like exterior to push past the uncanny valley of robotics? Sophia is an example of steps being taken to have humanoid robots naturally accepted by people . She is something of a celebrity, speaking at events and conferences. She’s become the first robot to be granted citizenship for a country (Saudi Arabia) and a robot VISA (to go on her World Tour). And while Sophia is a step towards the development of humanoid robots for social tasks and roles, crossing the uncanny valley could be an obstacle to making humans truly comfortable with the idea of interacting with robots.
Staff Writer, Signal to Noise Magazine
PhD Candidate, Department of Medicine/Division of Cardiology, UCLA
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