REPRESENTATION OF MOVING OBJECTS ALONG A ROAD NETWORK

Research has previously been conducted in the area of generating, indexing, modelling and querying network-based moving objects. However, little work has been done in building a calculus of relations between disconnected network-based mobile objects. In this paper an approach to qualitatively representing and reasoning about trajectories of pairs of objects moving along a road network is presented. We call this approach the “Qualitative Trajectory Calculus along a road Network” (QTCN). We start from the assumption that two objects are moving continuously towards each other or away from each other, and consider how to describe their joint trajectories. Since the distance between two objects is measured along the shortest path, specific attention will be given to changes in shortest path, and more specifically changes in direction of the velocity vector of an object with reference to the shortest path between two objects. A conceptual neighbourhood diagram is presented, that forms the basis for a representation of a conceptual animation.