What is "s-one"

S-One is a Japanese robot made by Tokyo-based company Schaft to compete in the Robotics Challenge, a DARPA-organized competition with an aim to "discover" the most up-to-date humanoid robots. It won the competition with 27 points out of 32 by completing tasks, such as clearing the ground of objects and passing through debris without difficulty. The S-One lost points when unable to exit from a vehicle.