Patent 7437214 was granted and assigned to Sony on October, 2008 by the United States Patent and Trademark Office.
A legged mobile robot can calculate the movement amount between a portion of the robot apparatus that had been in contact with a floor up to now and a next portion of the robot apparatus in contact with the floor using kinematics and to switch transformation to a coordinate system serving as an observation reference as a result of the switching between the floor contact portions.