A Double-Layer Subsumption Mechanism for Enforcing Sequential Behaviors in a Cognitive Architecture

This paper describes the design and implementation of a double-layer subsumption mechanism, used to integrate a plan-based subsystem with a subsumption architecture, within the MECA Cognitive Architecture. This mechanism enables MECA to benefit both from the flexibility of behavior, which is characteristic from Subsumption Architectures, and the regularity and previsibility of executing specific sequences of behavior, generated by a planning subsystem, in the cases when this is required. We provide a brief overview of the original design of MECA, explaining why such a scheme is an improvement in the original design, and what are its potential benefits regarding the architecture capabilities. In the sequence, we provide a detailed explanation of the new design, splitting the old architecture Behavioral Codelets into two new categories: Behavioral Codelets (with the same name, but a different functionality) and Activity Codelets, together with a new Activity Tracking Codelet for tracking plan execution. Finally, we consider the improved benefits of the new scheme.