Spontaneous and Privacy-friendly Mobile Indoor Routing and Navigation

Mobile indoor navigation systems guide users through buildings and premises by taking into account the current position of the user and a destination such as a room, office or shop. In many environments a spontaneous and also anonymous navigation is desirable e.g. at airports, hospitals or university campuses. However, many systems that have been proposed so far require the integration of a radio-based positioning system and access to other organization-specific systems, which results in a lot of things a user has to deal with before the navigation system can be used and which raises a lot of issues with respect to the location privacy of the user. In this paper we propose a mobile indoor navigation system that allows spontaneous navigation and that guarantees location privacy for the user. A pre-compiled compact representation for all the routes and navigation instructions in a building is the basis for an application that uses the built-in camera on the mobile device to derive the current position in the building from barcodes which are distributed all over the building. We show that the approach allows to navigate through a building with thousands of rooms and requires only little data on the device. Routes can be computed efficiently in O(1) on the device and the only infrastructure that is required are the barcodes which can be easily printed and installed at walls or already existing signs in the building.