SAPS: a production system with active data structures

SAPS (still another production system), a specialized forward chaining production system developed to support research in planning and plan recognition systems, is described. This planning research is based on mixed initiative development of military logistic and tactical operations plans. To support it, SAPS was designed with a flexible, innovative control structure and an unusual use of active plan nodes and data structures. SAPS synthesizes networks of independent, active nodes that support planning activities, an approach that applies to problem solving in general. SAPS views computation as a network of cooperating, independent nodes, each able to perform arbitrary computation. Each node is controlled by activating and deactivating rule sets assigned to it. Even though the same rule set can be assigned to several nodes, the control is by rule sets in each node. As an example, SAPS is applied to the n queens problem.<>