Distributed Integrated Scheduling in Automated Manufacturing Systems with Transient Machine Failures

For a just-in-time production scheme in large manufacturing systems we describe a considerable methodological extension into an integrated automated manufacturing system that is supported by a distributed real-time computer system. This allows for higher flexibility in demand fluctuation as well as for a larger variety of products. At the same time better adaptability of transportation planning and transportation cost reduction are achieved through their integration. For this integrated scheduling we will present new bidding algorithms. Eventually, in an extension of the presented scheduling algorithms, novel fault tolerant strategies are included for overcoming or neutralizing the effect of transient machine failures. These are handled by cooperating local schedulers and managed to guarantee a minimal damage of schedules and its propagation, in the presence of failures. Through their integration into the production and transportation scheduling the advantages of the just-in-time approach (no storage costs) are preserved in principle while a near-optimal way for the affected jobs is found to meet their deadlines. The results of our extensive simulation experiments for a real production scenario are also discussed.