Scheduling of storage/retrieval orders under a just-in-time environment

Abstract

We consider the problem of scheduling storage and retrieval orders under dual-command operations in a unit-load automated storage/retrieval system. The objective is to minimize the weighted sum of earliness and tardiness penalties about a common due date. We propose four heuristics based upon a two-step approach where dual-command cycles are formed first and then optimally scheduled. A mixed-integer programming model is also formulated to obtain an optimal solution. Performances of the heuristics are compared in the simulation tests. Computational results show that some heuristics perform favourably.

Additional information

Notes on contributors

M.-K. LEE

To whom correspondence should be [email protected].