ARIANNA: a smartphone-based navigation system with human in the loop

In this paper we present a low cost navigation system, called ARIANNA, primarily designed for visually impaired people. ARIANNA (pAth Recognition for Indoor Assisted NavigatioN with Augmented perception) permits to find some points of interests in an indoor environment by following a path painted or sticked on the floor. The path is detected by the camera of the smartphone which also generates a vibration signal providing a feedback to the user for correcting his/her direction. Some special landmarks can be deployed along the path for coding additional information detectable by the camera. In order to study the practical feasibility of the ARIANNA system for human users that want to follow a pre-defined path (by only using the smartphone feedback signals), we study how to incorporate human behavior models into the feedback control loop. We also implement an Extended Kalman Filter for localization, in which the user coordinates, speed and orientation represent the filter state (whose updating law depends on the user reaction to the vibration signals), while the smartphones sensors provide the set of measurements used for state estimation