Distributed multi-agent scheduling and control system for robotic flexible assembly cells

This paper deals with the development of a distributed multi-agent system (DMAS) for scheduling and controlling Robotic Flexible Assembly Cells (RFAC). In the proposed system, an approach for solving one of the most challenging decisional problems in RFAC is proposed and implemented. This problem is related to the products operations scheduling which requires their allocation and sequencing on the robots, while satisfying products and robots constraints under makespan minimization. The proposed DMAS addresses this challenge by using a cooperative approach supported by three kinds of autonomous control agents: supervisory agent, local agents, and remote agents. These agents interact by a negotiation protocol based on common dispatching rules for coordinating their individual decisions, satisfying their local objective and providing an optimized global solution. Moreover, because of the dynamic nature of the assembly systems, it is imperative to consider external disturbances on production scheduling and to solve the related issues. Consequently, DMAS has the ability to respond and manage some dynamic events that may occur in the cells such as unexpected robot breakdown or dynamic products arrivals. Computational results on benchmarks show the effectiveness and the robustness of the proposed system.