Computer Aided Design of Handwriting Trajectories with the Kinematic Theory of Rapid Human Movements

We present the Sigma Lognormal model as a potential tool for curve generation in computer graphics related applications. We discuss its extension and parameterisations for the interactive definition of handwriting, drawing and calligraphic trajectories. This results in an efficient trajectory synthesis method, that has a user interface similar to the ones commonly used with Bézier curves or splines, but with the added benefit of capturing the kinematics of human drawing or writing movements. Such kinematics produced by the model can then be exploited to generate realistic stroke animations or to facilitate expressive rendering methods.