Motion Doodles: A Sketching Interface for Character Animation

We present a novel system which allows a character to be sketched and animated within a minute and with a limited amount of training. The process involves two steps. First, a character is sketched by drawing the links representing the torso, head, arms, and legs. An articulated skeleton and mass distribution is then inferred from the sketched links. Further annotations can be added to the skeleton sketch and are automatically bound to the underlying links. Second, the desired animated motion is sketched using a series of arcs and loops that are interpreted as an appropriate sequence of steps, leaps, jumps, and flips. The motion synthesis process then ensures that the animated motion mirrors key features extracted from the input sketch. For example, the height, distance, and timing of an arc that represents a jump are all reflected in the resulting animated motion. The current prototype allows for walking, walking with a stomp, tip-toeing, leaps, jumps, in-place stomps, front flips, and back flips, including the backwards versions of all these motions.