The objective of the work described in this article is two-fold. First of all we aim to design a powered wheelchair driving simulator allowing to assess the driving skills of a person with disability and to facilitate the training. To make easier its duplication we chose a 3D software solution, the only feedback information being visual. The second objective consists in defining a quantitative evaluation method of the trajectories resulting from the experiments on simulator. For that, we base our study on a modeling of the pilot-wheelchair system while taking as a starting point the models described in the literature in the context of aircraft pilots or car drivers. Two case studies are presented to illustrate our approach.