Balance control of a biped robot in the coronal plane using foot sole CoP trajectories

This paper proposes a cooperative control scheme to achieve lateral balance of a biped robot in the coronal plane, tested under disturbing conditions such as changes in the floor inclination and external forces applied to the body. The control system is composed of one master controller in charge of commanding the legs servomotors and two proportional Fuzzy controllers, one for each foot, which compute the Center of Pressure (CoP) under each foot and generate a control action to move the hips-ankles servomotors in order to return the CoP to a stable region. Also describes the design and development of a four-point tactile sole which imitates the mechanical and sensing characteristics of human foot skin. Tactile soles are used to generate the CoP trajectories under the feet of the biped robot (Robonova from Hitec brand). Experimental results exhibit a good performance of the proposed cooperative control system for lateral balance.