
A couple of years ago we reported on a robot hand that could always win at the timeless hand game rock-paper-scissors or janken as it’s known here in Japan. After wrapping up, we confirmed that it would never lose, declared that the human race was doomed to sit in the back seats of our robot overlords, then called it a day.
Now we are surprised to learn that Tokyo University’s Ishikawa Watanabe Lab is back with an even better performing rock-paper-scissors robot, somewhat awkwardly dubbed the Janken Robot with 100% Winning Rate.
Like its predecessor, this model uses a camera to analyse the human player’s hand shape and using high-speed processing sends the result to the robotic hand at a speed of one millisecond. The robot hand then folds one, none, or all three of its fingers to correspond to the winning janken throw.
In addition to the fast analyzing and processing, the robot hand itself is able to move into 180 different positions in a tenth of a second, and its sense of vision is as fast as 1000 frames per second, over 30 times faster than a human.
All of this makes this version of the Janken Robot with 100% Winning Rate even faster than the previous model. Previously, it could detect and make its throw fractions of a second after its human opponent was done. Although in real time you’d hardly notice, when watching this video from two years ago, which includes slow-motion footage, we can see how delayed it is.
Nowadays, Ishikawa Watanabe Lab boasts that this rock-paper-scissors machine makes its throw before or at the same time as its human opponent. Observe, feeble humans!
In this video, we see that an Engadget Japan reporter use a human’s last resort weapon of unpredictability and also threw in a variation of scissors known as an inaka choki or otoko choki (boondocks scissors or man scissors, respectively) in which the player uses their thumb and index finger in a pistol-like configuration.
Doing so he was able to defeat the machine but the demonstrator called foul on the man’s trickery.
Ishikawa Watanabe Lab hopes that this technology will evolve into accident prevention systems for vehicles with its superhuman ability to detect movement and behaviors. However, if everything sci-fi movies have taught us over the years is correct, it can only lead to a super-fast armada of killbots who also always get to roll first in Monopoly. I bet they call dibs on the racing car, too…
Source: Ishikawa Watanabe Lab via Engadget (Japanese)
Videos: YouTube – Engadget Japanese, Ishikawa Watanabe Labratory


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