Fast EMG-data driven skin deformation

Virtual characters are being modeled and animated with increasing accuracy and photorealism in current games and virtual reality simulations. However, the detailed modeling of dynamic skin deformations due to movement of the muscles during articulation is still prohibitively expensive for real-time simulations. We present in this paper a fast approach for modeling such deformations driven by Electromyography (EMG) data. We demonstrate the method on the muscles of the upper leg during a gait cycle. A muscle map, created from a 3D muscle model, is applied as a deformation map to deform the skin surface as per the underlying muscle geometry. EMG signals recorded from a gait cycle are then used to dynamically vary the weights in the deformation map during animation thus producing the dynamic skin deformations. The whole operation is done on the GPU to make it very fast and suitable for real-time simulations. Copyright © 2009 John Wiley & Sons, Ltd.