A mobile navigation and orientation system for blind users in a metrobus environment

The research presented in this paper introduces a mobile assistant to spatially locate and orient passengers of a Metrobus system in the city of Mexico. The system assists blind passengers or passengers with limited eyesight. While most of the navigation systems developed so far for blind people employ a complex conjunction of positioning systems, video cameras, location-based and image processing algorithms, we developed an affordable and low-cost combination of mobile phone, GPS and compass device to provide the same range of functionalities. The mobile application is developed on top of a 3rd generation cell phone extended by GPS and digital compass devices. Interaction among these devices is achieved by using Bluetooth communications. Audible user-oriented interfaces indicate to a given user her/his location within the Metrobus system, i.e., appropriate instructions of orientation that lead to the boarding gates in that station, thanks to an orientation algorithm developed for this aim. The experiments have been performed on a Nokia N73 cell phone in a Metrobus line of the city of Mexico and validated by a panel of blind users.