http://www.nbcnews.com/tech/innovation/ ... ss-n350671
Oregon State University students have been working on a 2-legged chickenbot for DARPA dollars, seems it's much more energy-efficient than BigDog or Spot. 3x more energy efficient!
Stays upright when smacked with dodgeballs, even. I think the frame in the background is the support for the external power cable, to keep the beast from getting dragged off-balance by it's power cord.
Haqq bots for comparison: