Resolving object references in multimodal dialogues for immersive virtual environments

This paper describes the underlying concepts and the technical implementation of a system for resolving multi-modal references in virtual reality (VR). In this system the temporal and semantic relations intrinsic to referential utterances are expressed as a constraint satisfaction problem, where the propositional value of each referential unit during a multimodal dialogue updates incrementally the active set of constraints. As the system is based on findings of human cognition research it also regards, e.g., constraints implicitly assumed by human communicators. The implementation takes VR related real-time and immersive conditions into account and adapts its architecture to well known scene-graph based design patterns by introducing a so-called reference resolution engine. Regarding the conceptual work as well as regarding the implementation, special care has been taken to allow further refinements and modifications to the underlying resolving processes on a high level basis.