Check this out:
Very nice leg motions!
Reminds me of the Star Wars “Chicken” walkers!
Look at how top heavy that thing must be. 
Its amazing that stuff like that is even possible. It must be Big Dog’s master
Top heavy, yes. But for a “balancing” (and yes, a biped has a lot of balancing to do), it makes sense. Having an inverted pendulum configuration with a lot of weight up top means it can correct it’s stance (balance) if it encounters an upset (see video) faster, and avoid falling.
I’ll bet they re-used a lot of “code” (behaviors?) from Big Dog.
Alan KM6VV
Cool vid, i’ve seen this one before. The guys at boston dynamics are really masters of dynamic control. I bet they use really optimezed fuzzy logic and some powerfull processors to get it balanced especially with the heal-toe movements.
Very interesting!
Xan
A little update, its now able to walk at higher speed. It’s almost the same video, the higher speed walking can be seen at the end:
That’s very impressive. I would love to see it running. The leg has an unusual configuration at the hip location, and it seems to be an important part of the system. I wonder if they can achieve the same result using a conventional humanoid hip design?
I suspect the unusual design of the hip was a convienient way of duplicating the functions of a pelvis.
I saw that video and it is really nice work. Its motions are very effective and perfect movement of leg. Overall this work is well.