July 2006: This smooth walking NXT biped started as an improvement of the Alpharex walking mechanism: in fact, since I built the original humanoid, I disliked the rubber grip lever on right foot to make it turn. In my robot, each motor controls a leg and robot can turn quickly. It’s called Omni-Biped because it’s can walk in every direction. To walk straight, motors move at the same speed and in the same direction; to turn, motors turn in opposite directions. The foot design is based on the Alpharex one. As you can notice, I used motor as structural part of the leg.
This robot is described in detail in my book.