Mobile Agent Based Integration Framework for Flexible Dynamic Job Shop Scheduling

Although production scheduling has been extensively studied, it is limited in the scope of applications. A mobile agent based flexible dynamic scheduling framework is presented in this article as a scheme to integrate various scheduling models, approaches, and algorithms, and flexibly and autonomously adapt the disturbances in the shop floor. Therefore, such a mobile agent based framework can help expand the scope of applications in the production scheduling field. In this framework, there are three kinds of main agents, including order data agent, scheduling model agent, and cell data agent. The order and cell data agents are designed to acquire dynamically calculated and formatted data from the systems and devices. The scheduling model agent is designed to obtain the optimal solution for distributed manufacturing cells to achieve high performance, such as minimizing the energy consumption. Devices, such as machine tools, are integrated into the framework through intelligent embedded terminals, which can be used by human operators or triggered by sensors to acquire the real-time processing data and on-the-spot conditions. A C based multi-agent platform, which is called Mobile-C, is adopted to develop the mobile agents for real-time and resource constrained applications with interface to hardware in different execution environments. A computational experiment of energy-saving scheduling based on generic algorithm is presented to validate the proposed mobile agent-based dynamic scheduling framework.