On-line scheduling of a robotic manufacturing cell with stochastic sequence-dependent processing rates

Abstract

The problem of on-line production control for a robotic manufacturing cell producing parts of different types is analysed. The approach described in this paper expands the results of an earlier study so as to provide for sequence-dependent (deterministic or exponential) processing times at the cell. In addition, a novel production control strategy permitting temporary suspension of the cell's activities at certain decision epochs is formulated. Several numerical examples are given to illustrate the productive potential of this formulation. They seem to indicate the superiority of the new strategy presented here to earlier optimal control strategies in which the cell had to be active as long as it was unblocked.