Computer animation method and system for synthesizing human-like gestures and actions

A computer animation method for creating animated characters by creating a library of gesture actions to be selected in sequence by a user, comprising the steps of:

• defining each of the animated characters as having a plurality of at least ten universal joints, each of the universal joints being defined by rotational movement about three mutually orthogonal axes;
• via a software program, defining, for each action a set of parameters for each axis of rotation at each of the universal joints, the parameters including a maximum angle of rotation excursion, a minimum angle of rotation excursion and a speed of rotation;
• and
• rendering the animated characters as a function of the selection by the user, wherein the library of gesture actions includes at least one composite gesture action controlling a plurality of movements at a plurality of joints.

A method for creating animated characters that convey emotion through their gestures, comprising the steps of:

• (a) generating scene transformations and images to be rendered as a function of scalar input parameters;
• (b) determining, for each respective gesture at each frame of animation, a weight of a set of parameters representative of the respective gesture, wherein the respective gesture is invoked if a weight of the respective gesture is a nonzero value;
• (c) calculating values over time for the set of parameters of each of the gestures;
• (d) performing a weighted sum of values for each of the set of parameter within each of the gestures for which the parameter is defined;
• (e) analyzing the transformation matrices to produce scalar variables;
• and
• (f) modifying the weight of the set of parameters representative of at least one gesture as a function of the scalar variables and determining the scalar input parameters for generating corresponding scene transformations and images.

A computer animation system for creating animated characters that convey emotion through their gestures, comprising:

• a library of stochastically defined movement gesture actions;
• scene description modules programmed with information to simulate a natural motion of the gestures by the animated characters;
• a goal determination module for computing, for each of the gestures, a weight of a set of parameters representative of a respective gesture of the gestures to determine whether the scene description modules should simulate the respective gesture;
• and
• an analyzer receiving information from the scene description modules to convey to the goal determination module whether to increase, decrease or keep constant the weight of individual gestures
• to enable a smooth transition from one gesture to the next and restricting a character movement.

A computer animation system for creating animated characters which appear to move in a succession of image frames, said computer animation system comprising:

• a library of gesture actions programmed with information to simulate the natural motion of gestures as expressed by the movement of body parts thereof through joint angles;
• each joint angle being expressed by the parameters of rotation about three axes and the parameters including limits of rotation excursion and speed of rotation;
• and
• each frame having each character body part movement defined by the parameters at each axis of each joint,
• wherein transitions between gestures are achieved by simultaneously decreasing a weight of one gesture and increasing a weight of a subsequent gesture.

A computer animation method for creating animated characters which include a plurality of body members coupled at a plurality of joints and which perform movement gesture actions, the computer animation method comprising the steps of:

• selecting first and second different gesture actions from a library of stochastically defined movement gesture actions, the first gesture action being defined by values over time for a first set of parameters, the first set of parameters controlling a first movement at a first joint of the plurality of joints and a second movement at a second joint of the plurality of joints, the second gesture action being defined by values over time for a second set of parameters, the second set of parameters controlling a third movement of at least the first joint of the plurality of joints;
• rendering the animated characters as a function of the first gesture action;
• and
• during a predetermined time interval, further rendering the animated characters by diminishing a weight of the values of the first set of parameters of the first gesture action and simultaneously increasing a weight of the values of the second set of parameters of the second gesture action to provide a smooth transition between the first and second gesture actions, wherein the transition between the first and second gesture actions effect a first movement at the first joint without effecting a second movement at the second joint.