A Distributed Software Architecture for GPS-Driven Mobile Applications

The unique requirements of voice recognition can shape a software architecture in many ways that have proven effective for mobile and distributed applications. We show in this paper that extending the voice recognition model of translating utterances into sentences to include translating a variety of real-world events into a command protocol can create an architecture whose components operate identically on hand-held devices, man-portable or vehicle-borne units, notebook, or desktop computers. SANSE, a portable navigation and geographic information management system having several redundant user interfaces, is described. In SANSE a collection of distributed Interactors translate events-spoken words, input from GPS hardware, timers expiring, input from files or communication links, and direct manipulation actions-into SANSE commands that are sent to one or more Receivers, which can execute commands without regard to their source. The complete operation of this system can be captured in vocabulary of less than 70 words, small enough to provide speaker-independent operation yet rich enough to be broadly applicable. The architecture can be extended by adding new Interactor types without affecting the operation of the baseline system.