
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


Mankind Dealt Further Blow As Robot Which Never Loses at Rock-Paper-Scissors Is Developed
How to win at rock-paper-scissors: A three-step guide
Ken Shimura remembered for his huge contribution to the game Rock, Paper, Scissors in Japan
The simple beauty of Japan’s “rock-paper-scissors” culture
“Rock-paper-scissors-playing” cat in Japan knows exactly how cute it’s being【Video】
Japan’s real-world Pokémon hot spring’s first photos are here![Photos]
Krispy Kreme releases new limited-edition fox doughnuts at only four stores in Japan
Two new Sailor Moon art manhole covers are coming to Usagi’s real-world Tokyo neighborhood
KFC Japan’s “The American Burgers” include a pile of guilt
Gundam teams up with 300-year-old daruma maker for wood-carved anime mecha figures[Photos]
Japan’s izakaya pubs closing at record pace, failing to attract foreign tourists
Japanese government to allow desecration of flags on kids’ meals
Tokyo’s new extra-expensive ramen restaurant is dividing opinions, so we tried a bowl
What makes the Starbucks Japan chocolate terrine so popular?
Used chopsticks upgraded from “waste” to “valuable material” by Kawasaki City thanks to ChopValue
Kanji ice cream becomes a sell-out hit in Japan
Japan has a new cute and clever sunblock for cat lovers
Japanese temple burns to the ground, fire burning inside for 1,200 years unharmed
Japan’s instant ramen snack theme park features an athletic course even adults can enjoy
Krispy Kreme Japan is bringing two special donuts to the most-forgotten big city in the country
Pizza Hut Japan’s drinkable curry pizza is here – Is it all we dreamed it would be?[Taste test]
Starbucks Japan hoping fans will go bananas for its new mottainai banana affogato Frappuccino
Tokyo’s life-size Gundam anime mecha statue will be removed this summer
The average age of Japan’s hikikomori shut-ins is getting older, survey shows
Japan enters Golden Week vacation period, survey shows one in three plan to ride it out at home
Ichiraku Ramen-inspired ramen sets from Naruto anime pay homage to Naruto, Sasuke, and Sakura
Japan’s new Pokémon jackets give you the look and powers of the Kanto starter trio
Japan now has gyoza doughnuts, and they taste like no other doughnut we’ve tried before
Studio Ghibli releases new anime keychains that are like miniature figurines
This Tokyo Station sweets sensation sells out daily, but we finally got our hands on it
Japan’s human washing machines will go on sale to general public, demos to be held in Tokyo
Starbucks Japan releases new drinkware and goods for Valentine’s Day
We deeply regret going into this tunnel on our walk in the mountains of Japan
Starbucks Japan releases new sakura goods and drinkware for cherry blossom season 2026
Japan’s newest Shinkansen has no seats…or passengers [Video]
Major Japanese hotel chain says reservations via overseas booking sites may not be valid
Put sesame oil in your coffee? Japanese maker says it’s the best way to start your day【Taste test】
No more using real katana for tourism activities, Japan’s National Police Agency says
Japan reportedly adding Japanese language skill requirement to most common foreigner work visa
Japan’s 5.3 million beautiful Hitachi Nemophila flowers are now in full bloom[Photos]
Japanese netizens dismayed at abysmal win rate of Pepsi Japan’s rock-paper-scissors promotion