DARPA's Cheetah robot is already the fastest legged robot in history and keeps beating its own records. It beat its previous record of 18 mph with a 28.3 mph sprint on the treadmill. This is faster than sprinter Usain Bolt's record 27.78 mph 20-meter split during his record 2009 100-meter sprint. In this video, the robot cheetah reaches 28.3 mph.
Nina Sen is a frequent contributor to Live Science’s Life’s Little Mysteries series: an exploration and explanation of our world’s phenomena, both natural and man-made. She also writes astronomy photo stories for Live Science's sister site Space.com.