QRPC: A new qualitative model for representing motion patterns

The Qualitative Rectilinear Projection Calculus (QRPC), a new representation model based on planar trajectories, is presented in this work for describing qualitatively motion patterns. Several models have been developed for this purpose and by comparing them with our proposal we show that the proposed model results in an intuitive approach for representing, in any context, the kinematical behavior of two objects in motion on the plane through the possible relationships among the rectilinear projection of their trajectories. The paper is centered on the formal definition of the set of geometric relations in terms of the front–back and left–right dichotomies, and how by the composition of these relations, it can be possible enumerate an exhaustive set of qualitative states and the possible transitions among them. The complete iconic representation of the set of qualitative states defines the Conceptual Neighborhood Graph of the QRPC model. In order to illustrate how this qualitative representation can be used to analyze and describe the relative motion of two objects, some examples extracted from the traffic engineering field have been studied.