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Janken (rock-paper-scissors) Robot with 100% winning rate

Ishikawa Group Laboratory · 4.3M views · 2012-06-26 · 1:01

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Overview

A University of Tokyo demo of a rock-paper-scissors robot that always wins, using high-speed vision to read the human hand and respond faster than people can perceive.

On Hacker News

Cited as a vivid example of machines outpacing human reaction times and of high-speed robotic vision.

Discussed on HN; no positive recommendation is recorded in this export · HN mentions 2014–2020

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What people said

jcims · 2020-03 · Reference

High speed rock paper scissors champ - [VIDEO] Ishikawa Komuro Labs had a bunch of crazy high speed robotic vision and actuation system ~10 years ago. [LINK] if you watch the slow motion there's so much backlash in the system it's hard to believe it works at all, but somehow they factor all of that in. Crazy stuff. That said, for a little side project this is very cool. The simulation idea is dope and the end result is fun to watch.

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chillacy · 2020-02 · Reference

Perhaps a humorous example of this: a robot that always wins at rock paper scissors: [VIDEO] There's a fun parlor trick which takes advantage of human reaction time too: place a hundred dollar bill on the table, let the other party place their hand a few inches away, start your hand a foot above theirs; the first person to place their hand on the money wins, and the other party can start moving as soon as you start moving. Turns out you can easily go around their hand and grab the bill before they're able to react.

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chillacy · 2016-03 · Reference

I think a <200lb bipedal 2-arm robot which could box would be a marvel to see, but if there aren't any rules which say how many arms and legs the combatant has to have, the robot is gonna have wheels, most of its mass in the lower body so as to make it un-topplable, be made of some lightweight metal, and have an arm that plays chess and a boxing glove on an actuator that can break concrete. And on the point of existing rules, the existing rules aren't enough for this type of competition. First of all the weight class: are robots men or women? It says age 17+, how does that affect the robot? There's no rule against pouring water on the robot, but there also isn't a rule against releasing nerve gas. My robot is a pourous metal box with a canister of gas which renders everyone unconscious, do I win by K/O? Also, they already have battle robots, and they look nothing like conventional humans (one common design is a flat panel that slides under the opponent and jettisons them) As for reaction speed of man (100+ms vs machine), I'll just link this: [VIDEO]

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Sources

Video by Ishikawa Group Laboratory, played through YouTube.

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