Qualitatively Describing Objects Using Spatial Prepositions

The objective in this paper is to present a framework for a system that describes objects in a qualitative fashion. A subset of spatial prepositions is chosen and an appropriate quantiication is applied to each of them that capture their inherent qualitative properties. The quantiications use such object attributes as area, centers, and elonga-tion properties. The familiar zeroth, rst, and second order moments are used to characterize these attributes. This paper will detail how and why the particular quantiications were chosen. Since spatial prepositions are by their nature rather vague and dependent on context a technique for fuzzi-fying the deenition of the spatial preposition is explained. Finally an example task is chosen to illustrate the appropriateness of the quantiication techniques.