Dead reckoning for biped robots that suffers less from foot contact condition based on anchoring pivot estimation

Abstract

A novel technique of dead reckoning for high-rate feedback control of biped robots is proposed. A fast position estimation of a robot is achieved by fusing information only from internal sensors including joint angle encoders, inertial sensors and force sensors. It combines the kinematics computation and the double integral of acceleration in a complementary way in order to improve the accuracy. The kinematics computation takes the movement of supporting foot, particularly, rotation about a fixed point and rolling on the terrain into consideration. The weights on each information are adjusted automatically based on the reaction force from the ground as it is expected to reflect the certainty of the contact condition of each foot. The validity of the proposed method is verified through computer simulations.