DISTRIBUTED SCHEDULING OF FLEXIBLE MANUFACTURING SYSTEMS - STABILITY AND PERFORMANCE

We consider a manufacturing system producing several part-types on sev eral machines. Raw parts are input to the system. Each unit of a given part-type requires a predetermined processing time at each of several machines, in a given order. A setup time is required whenever a machi ne switches from processing one part-type to another. For a single mac hine system with constant demand rates, we present a class of Generali zed Round-Robin scheduling policies for which the buffer level traject ory of each part-type converges to a steady state level. Furthermore, for all small initial conditions, we show that these policies can be P areto-efficient with respect to the buffer sizes required. Allowing th e input streams to have some burstiness, we derive upper bounds on the buffer levels for small initial conditions. For non-acyclic systems, we consider a class of policies which are stable for all inputs with b ounded burstiness. We show how to employ system elements, called regul ators, to stabilize systems. Using the bounds for the single machine c ase, we analyze the performance of regulated systems implementing Gene ralized Round-Robin scheduling policies.