PHAT is developed from scratch to create scenarios where simulated humans recreate activities of daily living and with the capability of showing how the AAL system under development is going to be used. Indirectly, PHAT serves as well for requirements elicitation, since it will permit to simulate in advance what kind of scenarios are to be more relevant, what behaviour ought to be expected, and show the result in a real-time 3D animation.

The situation: A patient goes to the toilet for washing up his hands while a relative is cooking the dinner. The patient slips on some water in the bathroom and falls over. The relative goes to help him but he trips over with a bottle because of lack of light.