Evaluating Robot Posture Control and Balance by Comparison to Human Subjects using Human Likeness Measures

Posture control and balance are basic requirements for a humanoid robot performing motor tasks like walking and interacting with the environment. For this reason, posture control is one of the elements taken into account when evaluating the performance of humanoids. In this work, we describe and analyze a performance indicator based on the comparison between the body sway of a robot standing on a moving surface and the one of healthy subjects performing the same experiment. This approach is here oriented to the evaluation of human likeness. The measure is tested with three human-inspired humanoid posture control systems, the independent channel (IC), the disturbance identification and compensation (DEC), and the eigenmovement (EM) control. The potential and the limitations connected with such human-inspired humanoid control mechanisms are then discussed.