Recreating a robot from 60 AD

In 60 AD, Greek engineer Hero built a self-propelled and programmable cart to carry automata around a theater stage. According to University of Sheffield computer scientist Noel Sharkey, this was probably one of the earliest programmable robots ever. Recently, the editors at New Scientist built their own version of the bot. From the New Scientist blog:

Power (for Hero's cart) came from a falling weight that pulled on string wrapped round the cart's drive axle, and Sharkey reckons this string-based control mechanism is exactly equivalent to a modern programming language...

Our cart was made from a child's scooter, a broom handle, wood, string, and lead weights from an old sash window.

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