Bipedal Locomotion: Stopping and the Standing/Balance Gait

A bipedal locomotion system is synthesized to characterize some of the previously overlooked aspects of the locomotion process, specifically standing/balance and initiation and stopping. The locomotion system is described by a three-element three-dimensional model consisting of two lower limbs and an upper body. The system equations of motion are derived using variational methods, and are retained in their nonlinear form. The impulsive contact events of impact of the swing limb with the ground and transfer of support are incorporated into the model. Bipedal locomotion is synthesized through numerical simulations. Several control inputs are studied for establishing and sustaining the standing/balance gait. Subsequent motion is analyzed via phase-space portraits. It is shown that an impulsive torque is sufficient for establishing and controlling the standing/balance gait as well as steady locomotion.