3D simulation of navigation problem of people with cerebral visual impairment

Cerebral Visual Impairment (CVI) is a medical area that concerns the study of the effect of brain damages on the visual field (VF). People with CVI have difficulties in their mobility and they have behaviours that others find hard to understand due to their visual impairment. A branch of Artificial Intelligence (AI) is the simulation of behaviour by building computational models that help to explain how people solve problems or why they behave in a certain way. This paper describes a novel computational system that simulates the navigation problem that is faced by people with CVI. This will help relatives, friends, and ophthalmologists of CVI patients understand more about their difficulties in navigating their everyday environment. The navigation simulation system is implemented using the Unity3D game engine. Virtual scenes of different living environment are also created using the Unity modelling software. The vision of the avatar in the virtual environment is implemented using a camera provided by the 3D game engine. Filters that mimic visual defects are created automatically and placed in front of the visual field of the avatar. The filters are based on the visual field charts of individual patients. Algorithms for navigation based on the limited vision have also been developed to demonstrate navigation problems because of the visual defects. The results showed different actions for the navigation behaviours according to the patients’ vision, and the navigations differ from patient to another according to their different defects.