walking -- and this one's doing it under its own steam. This passive robotic frame requires no energy input, and is instead powered by its own weight and a gentle slope. The BlueBiped can be adjusted to match the proportions of any user, and researchers plan to use it to assist people who find it difficult to walk and transport unwieldy sports equipment. It already holds the Guinness world record for the longest distance walked by a bi-pedal robot, plodding 15 kilometers (9.32 miles) in a single 13-hour stroll. Those fearing the impending Robopocalypse can at least breathe a sigh of relief that -- like some other homocidal robots -- stairs still remain out of bounds.