Robotized Warehouse Systems: Developments and Research Opportunities

Abstract

Robotized handling systems are increasingly applied in distribution centers. They require little space, provide flexibility in managing varying demand requirements, and are able to work 24/7. This makes them particularly fit for e-commerce operations. This paper reviews new categories of robotized handling systems, such as the shuttle-based storage and retrieval systems, shuttle-based compact storage systems, and robotic mobile fulfillment systems. For each system, we categorize the literature in three groups: system analysis, design optimization, and operations planning and control. Our focus is to identify the research issue and OR modeling methodology adopted to analyze the problem. We find that many new robotic systems and applications have hardly been studied in academic literature, despite their increasing use in practice. Due to unique system features (such as autonomous control, networked and dynamic operation), new models and methods are needed to address the design and operational control challenges for such systems, in particular, for the integration of subsystems. Integrated robotized warehouse systems will form the next category of warehouses. All vital warehouse design, planning and control logic such as methods to design layout, storage and order picking system selection, storage slotting, order batching, picker routing, and picker to order assignment will have to be revisited for new robotized warehouses. 1 Introduction Warehouse operations tend to be labor intensive and require large space for facilities. Large buildings are needed to store the item assortment in racks, to move stock, to unload and load 1 trailers and containers, to inspect picked orders, and to allow trucks to maneuver in the yard and to dock them. With the advent of e-commerce, companies store millions of unique items and handle large and variable daily order volumes. On the other hand, the most laborious and expensive process, order picking, is repetitive, often suffers from poor ergonomics, and requires high-quality labor willing to work in shifts, which is often difficult to get. It is therefore not surprising that warehousing systems and processes are key candidates for automation. In addition, the land available for warehouses (which should preferably be close to the demand points) has become scarce, and many warehouses have to operate 24/7. Together, this has given warehouse automation a big boost. Warehouse automation dates back to the 1960s, when the first high-bay (20-40 m high was quite standard) unit-load warehouses were established in Germany with aisle-captive cranes driving on rails, constructed as a silo building (Industrieforum 2004). These so-called AS/R (automated storage and retrieval) systems were able to store bulk stock on unit loads (pallets, or totes: miniload system). They could also work in conjunction with manual pick stations as a parts-to-picker system, where the retrieved unit load was restored after picking units from it. Since then, AS/R systems have become very popular in practice, and research ...

A Flexible System for Stepwise Automation of Microbial Testing of Drinking and Process Water

“…The design of the system was inspired by the AGV's rack retrieval and shuttle systems, which are used particularly in warehouse automation. 22 Here, cargo has to be transported from storage areas such as shelves to packaging, subsequent treatment, or delivery destinations. Hence, for those tasks, such facilities share some similarities with laboratory institutions.…”

Decarbonizing warehousing activities through digitalization and automatization with WMS integration for sustainability supporting operations

“…Briefly, sustainable warehousing should positively affect all 3 pillars of sustainability: environmental, social and economic [19,20]. Sustainable warehouse management and characteristic belonging to sustainable warehousing are studied by researches, but not the role of WMS and automated systems in relation to sustainability environmental issues [21]. On the other hand, a multitude of publications, related to sustainable warehouse options for heating, lighting, water and energy consumption and waste management are easy to be found [22].…”

A “Push-Pull” rearrangement while routing for a driverless delivery vehicle

“…The entire literature review on the Puzzle-Based Storage system treats the System Analysis, Design Optimization or Operations Planning and Control (Azadeh, de Koster, & Roy, 2017), but does not address the rearrangement as we envisage it in our work. The following section sets out the problem statement.…”