Visualising emotion is a tricky thing to do. The Grimace Project has created a technology to try and do this - it was developed by Thomas Fadrus, Oliver Spindler. Grimace helps to show you what emotions look like. One of their key inputs was Scott MCloud's book Making Comics.
The Grimace System was developed out of a degree project at the Technical
University of Vienna. It can render human facial expressions, based on a
mixture of 6 essential emotions:
Images Copyright Grimace