A New Agents-Based Model for Dynamic Job Allocation in Manufacturing Shopfloors

摘要

Market-based mechanisms such as the contract net protocol (CNP) are very popular for dynamic job allocation in distributed manufacturing control and scheduling. The CNP can be deployed with different configurations of the system elements. Every configuration corresponds to a basic or a hybrid topology. The subject of topology is generally discussed in the field of “distributed systems.” Inspired from the notion of topology in the distributed systems, this paper proposes a ring-like model as a competitor for the web-like CNP-based job allocation within the concept of holonic manufacturing systems. Details of the algorithm for scheduling and assignment of jobs to resources in the ring structure is presented and its performance is compared with both CNP-based distributed model, and the centralized conventional scheduling of a real manufacturing case study involving a major turbine production plant. Comparison of performance indicators such as time and cost of operations shows that the distributed models clearly outperform the conventional practice with meaningful impact on the production economy. As a possible implementation strategy, a hybrid switching model, composed of both competing models, is proposed.