Multi-Segment Foot Modeling for Human Animation

We present a multi-segment foot model and its control method for the simulation of realistic bipedal behaviors. The ground reaction force is the only source of control for a biped that stands and walks on its feet. The foot is the body part that interacts with the ground and produces appropriate actuation to the body. Foot anatomy features 26 bones and many more muscles that play an important role in weight transmission, balancing posture and assisting ambulation. Previously, the foot model was often simplified into one or two rigid bodies connected by a revolute joint. We propose a new foot model consisting of multiple segments to accurately reproduce human foot shape and its functionality. Based on the new model, we developed a foot pose controller that can reproduce foot postures that are generally not obtained in motion capture data. We demonstrate the validity of our foot model and the effectiveness of our foot controller with a variety of foot motions in a physics-based simulation.