Zäzilia Seibold

GridStore: A Puzzle-Based Storage System With Decentralized Control

We describe a high-density storage system for physical goods in which identical conveyor modules can be plugged together to store and retrieve unit-loads or small containers. Material movement conforms to the “puzzle architecture” found in popular board games such as the 15-puzzle and Rush Hour. Control of the system is decentralized, meaning that each module contains identical operating logic that directs its behavior based on local conditions and message passing. We prove the system deadlock-free and show its performance under a wide variety of operating configurations.

Layout-optimized sorting of goods with decentralized controlled conveying modules

To increase flexibility in intralogistics, decentralized controlled material handling systems have been developed. We investigate the suitability of one of these systems, the FlexConveyor, for sorting of goods. The FlexConveyor is a material handling system built out of multiple, identical modules, each equipped with a controller. By communicating with each other, the modules are able to cooperate and to transport goods from any source to its specific destination. For sorting of goods, densely connected layouts promise high throughput while requiring little space. To compare different layouts, to identify bottlenecks and to draw conclusion about algorithm optimizations, we do a layout analysis partially based on methods coming from the network analysis of national transportation networks. The results of this layout analysis are compared to experimental results of a discrete event simulation model.

Safety requirements and safety functions for decentralized controlled autonomous systems

Flexibility and safety are important criteria for automated material handling systems. Autonomous and decentralized controlled systems are flexible but they also pose new challenges in safety. We describe KARIS, a decentralized controlled, autonomous intralogistic system and indicate the differences to conventional autonomous guided vehicles. Based on the results of a risk assessment, we point out the particular challenges to safety technology and describe the developed safety functions. They are evaluated and compared to required performance levels determined by the risk assessment.

Optimization of Failure Behavior of a Decentralized High-Density 2D Storage System

To meet the requirement of flexibility in intralogistics systems, the GridFlow 2D storage system has been developed which is able react to fluctuating processing volumes and layout changes. It consists of multiple autonomous conveyor modules, FlexConveyors, each equipped with a controller. The decentralized control can be described with a set of rules for the communication by message passing between the controllers of the FlexConveyors. In this paper an adapted control algorithm is presented which enables the conveyor modules to react to occurring failures in neighboring modules. It has been theoretically proved that the presented algorithm prevents system deadlock. Also the impact of occurring failures on the system performance has been examined through a Monte Carlo experiment using discrete event simulation.

Plug&Play-Fördertechnik in der Industrie 4.0

Fur die Umsetzung der Vision „Industrie 4.0“, in der Mensch und Maschine unter- und miteinander vernetzt sind, werden u. a. cyber-physische Systeme benotigt. Im Bereich der Intralogistik wurden in den letzten Jahren bereits mehrere Materialflusssysteme entwickelt, die diesen Anspruchen zumindest teilweise entsprechen, indem sie modular aufgebaut und dezentral gesteuert sind. In diesem Artikel werden zuerst gewunschte Eigenschaften von Fordertechniksystemen identifiziert, aus denen Gestaltungsregeln abgeleitet werden. Daraufhin werden Beispielsysteme vorgestellt, die diese Gestaltungsregeln befolgen, und es wird untersucht, inwieweit die gewunschten Eigenschaften erfullt sind. Im Fazit wird auf die zukunftigen Herausforderungen eingegangen.

Future Technologies in Intralogistics and Material Handling

This chapter describes future technologies in Intralogistics and Material Handling. Starting from a description of today’s material handling systems (including two case studies) and an analysis of their shortcomings we derive desirable properties for future material handling systems (basic section). The necessary functions for these systems are explained and samples of modern material handling systems are presented which at least partially implement these properties (advanced section). The state of the art of the challenging functions is explained and references for further reading are given.

Bestimmung der Leistungsverfügbarkeit eines modularen Sorters

Der GridSorter ist ein dezentral gesteuertes, modulares Fordersystem, das zur effizienten und platzsparenden Warensortierung genutzt werden und flexibel an wechselnde Anforderungen angepasst werden kann. In diesem Artikel wird ein Steuerungsverfahren vorgestellt, welches automatisch auf technische Storungen reagieren kann und somit einen kontinuierlichen Betrieb ermoglicht. Mittels Simulation wird der Einfluss von Defekten einzelner Module auf die Systemleistung untersucht.