A head movement propensity model for animating gaze shifts and blinks of virtual characters

An automatic model is presented for animating gaze shifts of virtual characters towards target locations in a virtual environment. Two connected components are described: an eye–head controller and a blinking controller. The gaze control model is based on results from neuroscience, and dictates the contributions of the eyes and head to a gaze shift according to an individual's head movement propensity; that is, their tendency to recruit their head when making gaze motions under different conditions. The blink controller simulates gaze-evoked blinking, a specific category of behaviours that accompany gaze shifts. The probability of occurrence of such blinks, and their amplitude, is related to the gaze shift. The model forms the basis for a number of experiments investigating the impact of blinking, eye–head ratio and direction of head movements on user perception. In addition to other application domains, the findings are of significance to serious games environments, where the perceived quality of a character's gaze may affect engagement, immersion and learning outcomes.

Gaze is a salient behaviour in the environment, providing an abundant source of information for others about entities’ possible intentions and imminent future actions. Animating the gaze of virtual characters such as this Embodied Conversational Agent called Greta, developed by Pelachaud and colleagues, is an important factor in creating credible environments and interactions that facilitate user engagement and immersion.Figure optionsDownload high-quality image (118 K)Download as PowerPoint slideResearch Highlights
► Gaze model for virtual agents based on human propensity to preferentially employ the eyes or head when making gaze shifts.
► Modelling of blinks that accompany gaze-shifts.
► Pilot study concerning human perception of blinking and gaze.
► Applications for the gaze model, including humanoid agents in serious games and HCI.