Boston Dynamics demonstrates “LittleDog”, a four-legged robot used to bring “supplies for troops.” Video after the break.

Each of LittleDog’s legs is powered by three electric motors, giving them a lot of flexibility. Sensors measure the angles of each joint as well as body orientation and foot/ground contact. The basic strategy for walking over both smooth and rough terrain is to adjust a smooth walking pattern generator with the selection of every foot placement such that the center of gravity � follows a stable trajectory

[via BotJunkie]