Dynamic emotional expression choreography: perception of naturalistic facial expressions

Animators and animation researchers have looked to the work of psychologists - most notably Paul Ekman and Wallace Friesen – to learn more about the movement and perception of facial expressions. The Facial Action Coding System (FACS) and six ‘universal expressions’ have formed the basis of numerous character animation tools and research projects. However, social science research tends to focus on how facial expressions are perceived, with little consideration to how manipulation of movement or timing can improve perception of emotion. Publications in the field of psychology are rarely accessible or even applicable to practicing animators. While practical guides to facial expression and facial animation exist, an animators’ guide to believable dynamic emotional expression - based on solid research into audience perception - has yet to be produced. In this paper, the authors describe the Emotional Avatars project – an art-led research project looking at the dynamics of emotional expressions. Specifically, the authors explain the theory of emotional expression choreography, consider how audience perception of emotion can be measured, and discuss how comparative studies of nature, acting, and animation could lead the production of a digestible guide to perceptually valid emotional expression animation.