An adaptative agent architecture for holonic multi-agent systems

Abstract

Self-organized multi-agent systems (MAS) are still difficult to engineer, because, to deal with real world problems, a self-organized MAS should exhibit complex adaptive organizations. In this respect the holonic paradigm provides a solution for modelling complex organizational structures. Holons are defined as self-similar entities that are neither parts nor wholes. The organizational structure produced by holons is called a holarchy. A holonic MAS (HMAS) considers agents as holons that are grouped according to holarchies. The goal of this article is to introduce an architecture that allows holons to adapt to their environment. The metaphor is based upon the immune system and considers stimulations/requests as antigens and selected antibodies as reactions/answers. Each antibody is activated by specific antigens and stimulated and/or inhibited by other antibodies. The immune system rewards (respectively penalizes) selected antibodies, which constitutes a good (respectively wrong) answer to a request. This mechanism allows an agent to choose from a set of possible behaviors, the one that seems the best fit for a specific context. In this context, each holon, atomic or composed, encapsulates an immune system in order to select a behavior. For composed holons, each sub-holon is represented by the selected antibody of its immune system. The super-holon's immune system therefore contains one antibody per sub-holon. This recursive architecture corresponds with the recursive nature of the holarchy. This architecture is presented with an example of simulated robot soccer. From experiments under different conditions we show that this architecture has interesting properties.