If you wonder how soon we will have walking robots, remember that the technology underlying the Segway was developed for a stair-climbing wheelchair.
From the article:
I had the opportunity to hear Dr. Herr speak at an MIT robotics conference last November. At the time, I knew nothing of his background or research. Halfway in to the presentation as he was describing his research, he rolled up the cuffs of his slacks to reveal metal and electronics. Until that point I’d had no idea he was a double amputee; as he’d walked to the front of the room, his gait — though not completely normal — was so smooth, I’d never have guessed he was dealing with anything but a couple of stiff joints.