Intelligent Component-Based Automation of Baggage Handling Systems With IEC 61499

Airport baggage handling is a field of automation systems that is currently dependent on centralized control systems and conventional automation programming techniques. In this and other areas of manufacturing and materials handling, these legacy automation technologies are increasingly limiting for the growing demand for systems that are reconfigurable, fault tolerant, and easy to maintain. IEC 61499 Function Blocks is an emerging architectural framework for the design of distributed industrial automation systems and their reusable components. A number of architectures have been suggested for multiagent and holonic control systems that incorporate function blocks. This paper presents a multiagent control approach for a baggage handling system (BHS) using IEC 61499 Function Blocks. In particular, it focuses on demonstrating a decentralized control system that is scalable, reconfigurable, and fault tolerant. The design follows the automation object approach, and produces a function block component representing a single section of conveyor. In accordance with holonic principles, this component is autonomous and collaborative, such that the structure and the behavior of a BHS can be entirely defined by the interconnection of these components within the function block design environment. Simulation is used to demonstrate the effectiveness of the agent-based control system and a utility is presented for real-time viewing of these systems. Tests on a physical conveyor test system demonstrated deployment to embedded control hardware. Note to Practitioners-It is well recognized that flexibility and reconfigurability of manufacturing systems pose a major challenge to their automation. There is also a belief among automation researchers that decentralized intelligent control will contribute significantly to the flexibility of manufacturing systems. Achievements in practical applications using decentralized control have been limited by the standing tradition of automation design with centralized logic executed on programmable logic controllers (PLCs). The new programming architecture defined by IEC 61499 is specifically designed for distributed applications and invalidates many existing assumptions about the difficulty of implementing these systems using partially or fully decentralized execution. In this paper, we present results of developing a distributed automation architecture based on IEC 61499 for airport baggage handling systems. Such systems are constantly undergoing reconfiguration, repair and expansion so flexibility is a vital design metric. We demonstrate several sides of "flexibility" enabled by IEC 61499, including component reuse, maintenance and human interaction, and reconfiguration.