Reference: Hayes-Roth, B.; Johnson Jr., M. V.; Garvey, A.; & Hewett, M. A Modular and Layered Environment for Reasoning about Action. 1987.
Abstract: An intelligent system reasons about--controls, explains, learns about--its actions, thereby improving its efforts to achieve goals and function in its environment. In order to perform effectively, a system must have knowledge of the actions it can perform, the events and states that can occur, and the relationships among instances of those actions, events, and states. The BB* environment represents this knowledge in an abstraction hierarchy and defines uniform standards of knowledge content and representation for modules within each of three hierarchical levels: architecture, framework, and application. Conversely, a BB* system layers application knowledge on an appropriate framework, which it layers on an appropriate architecture. During problem- solving, the architecture uses a generic framework interpreter to interpret these several layers of representation. We illustrate BB* with some of its current modules: (a) the BB1 blackboard control architecture; (b) the ACCORD framework for arrangement-assembly tasks; and (c) several domain-specific applications of BB1-ACCORD. We demonstrate BB* advantages for: system representation and performance; system design and implementation; reusable knowledge modules; and open system integration. We view BB* as both a modular and layered AI computing environment and as an elementary theory of intelligence.