ABSTRACT -- This paper describes our preliminary research in analyzing mechanical structure and its stability of a humanoid robot, to be designed and built at FIBO. Mobility and gaits of such a robot are governed by only two legs, leading to high complexity in dynamic control. We have thoroughly measured positions, velocities and accelerations of each joint of human legs in order to understand their profiles. We are in a process of designing geometry of the robot legs, based on such measured profiles. In addition, we have proposed the robot gaits with related analysis on kinematic and dynamic stability. Finally, a planar two degree of freedom inverted pendulum (PTIP) has been built as a testbed to implement our controller for balancing one leg. Simulation results and discussion are included herein.

KEYWORDS -- Humanoid robot, Stability, Gait