Workers check the function of the hydraulic arms of a London bus that is being transformed into a robotic sculpture by Czech artist David Cerny in Prague July 2, 2012. The bus, which Cerny hopes could become an unofficial mascot of the London 2012 Olympic Games, does push-ups with the help of an engine powering a pair of robotic arms, and the motion is accompanied by a recording of sounds evoking tough physical effort. It will be parked outside the Czech Olympic headquarters in London for the duration of the Games. Picture taken July 2, 2012. REUTERS/Petr Josek (CZECH REPUBLIC - Tags: ENTERTAINMENT SPORT OLYMPICS) Published: Čec. 22, 2012, 5:58 odp. | Foto: Reuters