Spatio-Temporal Predicates

This paper investigates temporal changes of topological relationships and thereby integrates two important research areas: first, two-dimensional topological relationships that have been investigated quite intensively, and second, the change of spatial information over time that has recently been identified as an important research topic. We investigate spatio-temporal predicates, which describe developments of well-known spatial topological relationships. We describe a framework in which spatio-temporal predicates can be obtained by temporal aggregation of elementary spatial predicates and sequential composition. We compare our framework with two other possible strategies: one is based on the observation that spatio-temporal objects correspond to three-dimensional spatial objects for which existing topological predicates can be exploited. The other approach is to consider possible transitions between spatial configurations. These considerations help to identify a canonical set of spatio-temporal predicates.