An improved articulated model of the human hand

We present an improved anatomically based approach to modeling the human ha nd for use in the animation of the American Sign Language. The joint rotati ons in the model are based on the bone and muscle configurations of the han d, and a forward kinematic solution is used to position the hand. In partic ular, we investigate the rotations of the base joint of the thumb. This joi nt is a saddle joint with nontrivial rotational axes and centers, and must be treated with care in such a model. We take advantage of several correlat ions between joint rotations in the hand to reduce the number of degrees of freedom in the model and to provide a simple, natural, and interactive int erface for American Sign Language handshape transcription.