Three-dimensional Fitt's law model used to predict movement time in serious games for rehabilitation

Abstract

Virtual reality serious game platforms have been developed to enhance the effectiveness of rehabilitation protocols for those with motor skill disorders. Such systems increase the user's motivation to perform the recommended in-home therapy exercises, but typically don't incorporate an objective method for assessing the user's outcome metrics. We expand on the commonly used human modeling method, Fitt's law, used to predict the amount of time needed to complete a task, and apply it as an assessment method for virtual environments. During game-play, we compare the user's movement time to the predicted value as a means for assessing the individual's kinematic performance. Taking into consideration the structure of virtual gaming environments, we expand the nominal Fitt's model to one that makes accurate time predictions for three-dimensional movements. Results show that the three-dimensional refinement made to the Fitt's model makes better predictions when interacting with virtual gaming platforms than its two-dimensional counterpart. © 2014 Springer International Publishing.