Robo-Butt Gives New Meaning to Uncanny Valley

SHIRI Robotic Buttocks
A Japanese artist strokes the SHIRI robotic butt to get a robot reaction. (Image credit: University of Electro-Communications Tokyo)

A robotic butt named SHIRI touches upon every nook and cranny of the uncanny valley, especially as a human pokes, slaps and strokes its fleshlike surface. It's downright creepy.

SHIRI is a Japanese art project that seems designed to ring all sorts of alarm bells in the human brain. "Shiri" literally means "buttocks" in Japanese, according to Kotaku editor Brian Ashcraft, and the robot, which is described in a video by its creators as a "buttocks humanoid," twitches and ripples. The creepy sensations triggered by the robotic butt's responses touch upon almost every aspect of the "uncanny valley" phenomenon coined by Japanese roboticist Masahiro Mori in 1970.

The uncanny valley in how people perceive lifelike objects remains poorly defined, but researchers have put their fingers on a few clues that could explain its mystery. Human brains include finely tuned detectors for telling what is or is not a real human being, but nonhuman objects or images can confuse the brain by displaying even one realistic human behavior or appearance — perhaps the root cause of the uncanny valley sensation.

Nobody would ever mistake SHIRI, a mechanism that appears to have been neatly detached from a person's waist and upper thighs, as a living human being, but part of the robot's creepy factor comes from appearing to be alive all by itself. The Japanese artists who made SHIRI step up the creepiness in their video, which at one point shows the robotic butt flexing in time to the sound of a heartbeat — an uncanny combination of realistic human sights and sounds. [Why Creepy Uncanny Valley Keeps Us on Edge]

The video reveals another element of the robot's creepiness by showing the silicon "human" skin peeled away and draped over the bottom of SHIRI's mechanical skeleton. The scene resembles an incomplete cyborg surgery or humanoid robot assembly, evocative of scenes in science fiction films such as "The Terminator" series, where assassin cyborgs peel back their human skin or facades to reveal robotic guts.

Even creepier scenes come from watching a person prodding, slapping and massaging the robotic butt to trigger reactions such as "tension, "twitch" and "protrusion." Such interactions verge uncomfortably on mental territory normally associated with sex — and it's not hard to imagine SHIRI as one piece of a humanoid sexbot from the future.

But the Japanese artists from the University of Electro-Communications in Tokyo don't appear to have created SHIRI with sexbots in mind. They seem much more interested in screwing with people's heads by suggesting SHIRI can have its own emotions, and by speculating about people's possible reactions.

"They may feel SHIRI's fear when they trigger SHIRI's 'twitch' upon first contact," according to the SHIRI video's captions. "And similarly the user may also feel SHIRI's happiness when a gentle stroke is applied triggering a "protrusion.'"

That choice of narrative words may actually be the creepiest part of all.

Luckily, the video ends comically when the unseen person gives the robotic butt a hearty final slap and abruptly walks away. You're walking out of the uncanny valley … take a deep breath … it's gone. For now.

This story was provided by InnovationNewsDaily, a sister site to LiveScience. You can follow InnovationNewsDaily Senior Writer Jeremy Hsu on Twitter @ScienceHsu. Follow InnovationNewsDaily on Twitter @News_Innovation, or on Facebook.

Jeremy Hsu
Jeremy has written for publications such as Popular Science, Scientific American Mind and Reader's Digest Asia. He obtained his masters degree in science journalism from New York University, and completed his undergraduate education in the history and sociology of science at the University of Pennsylvania.