Abstract
Intelligent agents perform multiple concurrent taks requiring both knowledge-based reasoning and interaction with dynamic entities in the environment, under real-time constraints. Because an agent's opportunities to perceive, reason about, and act upon the environment typically exceed its computational resources, it must determine which operations to perform and when to perform them so as to achieve its most important objectives in a timely manner. Accordingly, we view the problem of real-time performance as a problem in intelligent real-time control. We propose and define several important control requirements and present an agent architecture that is designed to address those requirements. The proposed architecture is a blackboard architecture, whose key features include: distribution of perception, action, and cognition among parallel processes, limited-capacity I/O buffers with best-first retrieval and worst-first overflow, dynamic control planning, dynamic focus of attention, and a satisficing execution cycle. Together, these features allow an intelligent agent to trade quality for speed of response under dynamic goals, resource limitations, and peformance constraints. We illustrate application of the proposed architecture in the Guardian system for surgical intensive care monitoring and contrast it with alternative agent architectures.
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This research was supported by DARPA contract N00039-83-C-0136, NIH contract 5P41-RR-00785, EPRI contract RP2614-48, and AFOSR contract F49620-89-C-0103DEF, and by gifts from Rockwell International, Inc. and FMC Corporation, Inc. The Guardian system is being developed in collaboration with Adam Seiver, Rich Washington, David Ash, Rattikorn Hewett, Anne Collinot, Luc Boureau, Angel Vina, Ida Sim, and Michael Falk. The paper's treatment of real-time requirements reflects discussions with colleagues involved in the AFOSR Program on Intelligent Real-Time Problem Solving Systems-especially Stan Rosenschein, Lee Erman, and Yoav Shoham. The paper also benefited from constructive criticism by several anonymous reviewers. Thanks to Ed Feigenbaum for sponsoring the work at the Knowledge Systems Laboratory.
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Hayes-Roth, B. Architectural foundations for real-time performance in intelligent agents. Real-Time Syst 2, 99–125 (1990). https://doi.org/10.1007/BF01840468
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DOI: https://doi.org/10.1007/BF01840468