Japanese robot fans took their own specially-designed robots to the ring so they could slug it out with other competitors. Some 25 powerful contestants from around Japan gathered for the Robo-One ground championships on Saturday (December 1) at Tokyo's convention centre to decide who was the strongest two-legged robot in the world. The spectacle bore a striking resemblance to a real boxing or mixed martial arts match as robots traded jabs, dodged punches and eventually knocked out opponents with a crushing blow. Hundreds of spectators huddled around the octagon to watch the heated battles. Only robots which could walk with two legs were eligible to fight and they had to be designed and constructed from the scratch by amateurs. The purpose of the battle was to knock out an opponent three times or push them off the octagonal ring. Two accidental slips are considered a knock-down. Robots exchanged punches for three-minute rounds and when a winner didn't emerge at the end of the round,...