Qualitative spatial reasoning: The CLOCK project

The manipulation of images to handle indeterminacy in spatial reasoning

“…Several axiomatizations are based on an extension of interval logic (Allen, 1983;Ligozat, 1991;Malik & Binford, 1983;Mukerjee & Joe, 1990). Brooks (1981) used generalized cylinders to reason symbolically about the shapes of objects, Forbus, Nielsen, and Faltings (1991) introduced a place vocabulary for qualitative dynamics, and Kaufmann (1991) based an axiomatization of spatial relations on the notion of tolerances. Finally, more quantitative axiomatizations refer explicitly to a real-valued, threedimensional coordinate system to capture the semantics of spatial prepositions (Davis, 1990).…”

Qualitative Spatial Reasoning: Framework and Frontiers

“…[12,13,14]). A more complete examination of the relevant literature and its relation to this model can be found in [11]. As the household robot example suggests, we believe the ]VfD/PV model is relevant to path-planning problems.…”

“…The creation of reliable mechanical clocks was a milestone in mechanical engineering; thus the development of systems which can reason about such mechanisms serves as a good milestone for qualitative spatial reasoning. One milestone, the qualitative simulation of a mechanical clock from first principles, was achieved in February 1988 by the CLOCK system [10,11], built by Paul Nielsen and Boi Faltings as part of their Ph.D. theses.…”

“…Our crispest statement of this ides is the Poverty Conjecture [10,11]: There is no problem.independent, purely qualitative representation of space or shape. By "purely qualitative," we mean to rule out representations whose parts contain enough detailed information to permit calculation or the operation of perceptual-like processing.…”

Qualitative Spatial Representation and Reasoning

“…13.1(c) it is not so satisfactory-the smaller region appears to be contained in the larger. 1 Early attempts at qualitative spatial reasoning within the QR community led to the 'poverty conjecture' [84]. Although purely qualitative representations were quite successful in reasoning about many physical systems [209], there was much less success in developing purely qualitative reasoners about spatial and kinematic mechanisms and the poverty conjecture is that this is in fact impossible-there is no purely qualitative spatial reasoning mechanism.…”