A flexible architecture for autonomous agents

Abstract

A generic architecture for autonomous agents is presented. In common with other current proposals the agent is capable of reacting to and reasoning about events which occur in its environment, executing actions and plans in order to achieve goals in its environment, and communicating with other agents. The work described here proposes certain advances on other systems, notably the ability to reason about and make decisions under uncertainty, including decisions about competing beliefs and alternative actions. The framework is grounded in a non-classical decision model, the ‘domino’ model. This is formalized to ensure continuity with classical decision theory and avoid ad hoc features. The domino model is embodied in a well-defined knowledge representation language, R2L, which explicitly supports the central concepts of decisions and plans, and associated constructs of goals, arguments, commitments, obligations and constraints. The availability of such a language provides a sound basis for building knowledge-based agents for practical applications. A major issue for such applications, however, is how to ensure their safe operation. This is a central issue whether the agents are used in an advisory role (e.g. decision support systems) or an autonomous one (e.g. in a robot). Techniques for explicit management of safety are described and some broader theoretical implications are discussed.