Puzzle-based storage systems (PBSs) can achieve very high utilization of expensive and scarce storage space coupled with fully automated storage and retrieval of unit loads. A PBS system with one empty cell is comparable to the well-known 15-puzzle, in which 15 tiles slide in a 4×4 grid. This...

Warehouse operations are rapidly becoming more robotized to increase performance and cut costs. One important new way of working is in collaboration between humans and robots. However, even though humans and their behavior remain essential for operational performance, human factors in...

Robot-based compact storage and retrieval systems (RCSRS) have seen many implementations over the last few years. In such a system, the inventory items are stored in bins, organized in a grid. In each cell of the grid, a certain number of bins are stored on top of each other. Robots with...

The order batching problem (OBP) is the problem of determining the number of orders to be picked together in one picking tour. Although various objectives may arise in practice, minimizing the average throughput time of a random order is a common concern. In this paper, we consider the OBP for a...

Internal transport systems using automated guided vehicles (AGVs) are widely used in many facilities such as warehouses, distribution centers and transshipment terminals. Most AGV systems use online dispatching rules to control vehicle movements. In literature, there are many types of...

This paper presents a review on design and control of automated guided vehicle systems. We address most key related issues including guide-path design, estimating the number ofvehicles, vehicle scheduling, idle-vehicle positioning, battery management, vehicle routing, and conflict resolution. We...

We study the case of a catalogue/internet mail order retailer selling seasonal productsand receiving large numbers of commercial returns. Returned products arriving beforethe end of the selling season can be resold if there is sufficient demand. A single orderis placed before the season starts....

This work aims at investigating the influence of picking batch size to average time in system of orders in a one-aisle warehouse under the assumption that order arrivals follow a Poisson process and items are uniformly distributed over the aisle's length. We model this problem as an M/G[k]/1...

A unique controlled field experiment investigates order picking performance (in terms of productivity and quality). We examined three manual picker-to-parts order picking methods (parallel, zone, and dynamic zone picking) under two different incentive systems (competition- based versus...

In the warehouse of Ankor, a wholesaler of tools and garden equipment, various problems concerning the storage and retrieval of products arise. For example, heavy products have to be retrieved prior to light products to prevent damage. Furthermore, the layout of the warehouse differs from the...