Postural balance strategies for humanoid robots in response to disturbances in the frontal plane

We examine human body reaction patterns to disturbances in the frontal plane while standing with the aim of developing balance control strategies for humanoid robots. Four reaction patterns are identified and related to the magnitude of the disturbance. Models for two of them are then developed and implemented with a humanoid robot HOAP-2. Special attention is paid to the transitions between the reaction patterns. The experimental data show that the models and controllers are appropriate and ensure smooth reaction control under both impact-force and continuous-force disturbances.