A synchronization mechanism for distributed manufacturing simulation systems

摘要

A simulator plays an important role in designing new manufacturing Systems. As manufacturing systems are being created on larger and more complicated scales than ever before, it is increasingly necessary to have opportunities to design a manufacturing system with several persons concurrently. In this case the designers often use suitable discrete event simulators for evaluating their assigned subsystems. After the subsystems are evaluated, it is necessary to evaluate the whole system. In order to evaluate the manufacturing system, the designers need to make the manufacturing system model by synchronizing several different simulators. In such distributed simulation systems using discrete event simulators, it is important to manage a distributed simulation clock and each simulator clock, and define interfaces among the simulation models. With the simulation clock, it is often necessary to perform rollback. The rollback function is to return the simulation clock to passed time to synchronize events among the simulations. However, most commercial based simulators do not include the rollback function. The purpose of this research is to develop a distributed simulation synchronization method including a function for managing distributed simulation clocks without the rollback function and interfaces among simulation models. In this paper, we propose a storage model concept as the method. We develop an algorithm to implement the proposed concept, and develop a distributed simulation system configuration using HLA. A case study was then carried out to evaluate the performance of the cooperative work.