From Measurements to Model: the Walk Engine

The present paper gives an overview of the modeling starting at the motion acquisition stage with an optical system and leading to a flexible real-time walk engine dedicated to the animation of autonomous virtual humans. First, we briefly describe how human motion acquisition process is done with a commercial optical system, stressing the remaining weaknesses regarding human motion measurements. We then recall the structure of the walking pattern that emerges from the findings of multiple biomechanics studies. In short, with proper normalization, time warping technique and mapping, it is possible produce on the fly a realistic walking pattern with continuously evolving velocity. Apart an intrinsic real-time requirement the described walking model addresses three issues: generalization (animation of a wide population of virtual humans for a wide range of the walking parameters), openness (user-defined personification of the gait style) and reactivity (changing the user defined context at any time while maintaining the coherence of the model).