 The position of the zero moment point is affected by the referred mass and inertia of the robot's torso, since its motion generally requires large angle torques to maintain a satisfactory dynamical postural stability.One approach to solve this problem consists in using small trunk motions to stabilize the posture of the robot.However, some new planning methods are being developed to define the trajectories of the legs’ links in such a way that the torso of the robot is naturally steered in order to reduce the ankle torque needed to compensate its motion.