Flexible Material Flow Research Articles

Design of matrix production systems: A skill-based systems engineering approach

A high changeability of value creation enables manufacturing companies to constantly adapt to new situations in Industry 4.0 such as changing product portfolios or supply chain disruptions. Matrix manufacturing systems provide a high changeability of value creation enabled by individually plannable process modules, interconnected through a flexible material flow. Higher maturity levels of matrix manufacturing systems integrate transportation and value creation tasks and are facilitated by location-independent equipment that merges into new resources according to dynamically changing manufacturing demands, i.e., a fluid production. The efficacious design of matrix manufacturing systems is still a complex challenge for research and practice. For this purpose, the authors propose a novel design approach specifically scoped for matrix manufacturing systems. This approach aims at offering a more practical guideline for the design of matrix manufacturing systems. Skill-based systems engineering provides the methodological foundation. The application opportunity for novel generative AI tools is exemplified. An experiment, addressing the manufacturing of a toy action figure, validates and improves the conceptualized design approach.

Axiomatic design of matrix production systems

Manufacturing companies are operating in a turbulent business ecosystem that demands for product variety, product mix flexibility, volume scalability and high efficiency. Personalized production arises as new production paradigm to replace mass personalization and changeable matrix production systems are well suitable to cope with the challenges of this new production paradigm. In this paper, a method to design the value-add process modules of a matrix production systems is presented. The method is based on Axiomatic Design. The approach works process oriented, pursues a modular layout, and a flexible material flow in the production system. The paper concludes with a validation of the method performed in an industrial use case.

Usage of Autonomous Mobile Robots Outdoors - an Axiomatic Design Approach

Industry 4.0, growing material supply chains, and changing logistics structures require flexible material flow solutions. As a result of this development, the usage of autonomous mobile robots (AMRs) is increasing significantly. Although there has been much research undertaken on the design of indoor AMRs, there is a lack of research regarding outdoor systems. Weather and road conditions are still challenging for sensors and actuators. Furthermore, requirements regarding the system, which must be known and met beforehand to guarantee industrial applicability, are yet to be sufficiently determined. This paper aims to close this gap and identify functional requirements through Axiomatic Design, which is used to develop design guidelines for practitioners. Starting with a systematic literature review and semi-structured interviews, the authors gather basic customer requirements. These customer requirements will then be analyzed to define functional requirements. Through a mapping and top-down decomposition process, the research team deduces design solutions for using outdoor AMRs. These requirements and solutions will be transformed into guidelines, which help system designers to improve the implementation of AMRs on the factory premises.

Algorithm for High-Throughput Scheduling of Paced Sequences

Sustainable production systems are characterized by systematic order control and scheduling to increase performance. Efficient scheduling considers all restrictions that occur during order processing, to achieve high utilization. This includes safety margins for ad hoc changes and in particular the scheduling of temporarily paced sequences. After processing these orders, the organizational process is carried out with a highly flexible material flow similar to job shop production. This paper describes an algorithm for the efficient planning of temporarily paced sequences during scheduling of a high-throughput system, in order to achieve an optimal utilization in the planning phase.

Sustainable Intralogistics due to Uniform Software and Modular Transport Entities

The current trend in internal value stream structures shows a clear development towards a combination of the specific advantages of the operation-oriented and the process-oriented production systems. All scientific approaches have in common that flexible intralogistics production networks require an autonomous and intelligent transportation systems that is not designed for a specific task, but can take on different transport roles due to their versatility. However, a comprehensive analysis of current designs and research projects in the field of AGVs and intralogistics transport robots show that there is neither the necessary interoperability of different systems nor a system architecture that addresses a flexible material flow independent of the physical design of the transportation system. AGVs mainly have a central control system, which manages the generation of transport orders and their disposition on the vehicles. In addition, the routes are specified centrally for the vehicles, even if they have free navigation. The individual transport unit is therefore only an executing machine that processes the assigned transport orders without any influence on order dispatching or route planning. Therefore, these AGV approaches do not have the flexibility and autonomy required for an intralogistics production network. The research project addresses the necessary interoperability of logistics systems and the abandonment of proprietary standalone solutions. For this purpose, methods for digitizing the workspace, route planning and path execution using a service-oriented architecture (SOA) were developed. A central component of this architecture is the approach described in the paper to enable decentralized path planning on the vehicles. Therefore, the path planning must be applicable to different target platforms without implementation effort and the vehicle software must be designed independently of the application. This approach allows intralogistics systems to be flexible and adaptable, resulting in a more sustained use of these systems.

Order Release for Temporary Paced Sequences in Flexible High Throughput Systems

Material testing in high-throughput systems facilitates a fast, precise and innovative method for the identification of metals with required characteristics. This material testing setup leads to highly flexible material flow between test stations similar to job shop fabrication. Various requirement specific test plans and the occurrence of temporarily paced sequences between subsequent processes amplify the necessity of controlling the material flow to reduce idle times and increase utilization. This paper introduces a concept of controlling temporarily paced sections in highly flexible systems, which improves the productivity of the entire system.

Coordinating material and information flows with supply chain planning

PurposeThe purpose of this paper is to study how companies can select a supply chain planning (SCP) mechanism to improve the balance between material flow and information flow.Design/methodology/approachThe methodology of the paper is an inductive case study approach. Coordination theory is used as a background for the paper. Based on a literature survey, determinants of the selection of a SCP approach are defined. Cases of SCP are used to validate the framework presented.FindingsThe paper suggests that specific supply chain characteristics need to be balanced by selecting a coordination mechanism that uses information optimally to support the material flow. Flexible material flow needs frequent updates of the plan based on accurate information. If frequent information sharing and planning practices are used to support inflexible material flow, the result may be volatility in plans, and planning resources are wasted. If a flexible material flow is supported by inadequate information, waste may be produced in the material flow, in the form of excess inventories or capacity.Research limitations/implicationsThe paper presents a framework for finding the balance between information flows and material flows and for applying a coordination mechanism.Practical implicationsCompanies can use the framework to analyse the management of their material flow and their use of information. In future research the framework could be developed to give more support for situations with different levels and sources of uncertainty.Originality/valueThe framework provides a new perspective on the discussion how information should be used to improve supply chain performance.

Einführung der Agententechnologie in einem produzierenden Unternehmen — ein Erfahrungsbericht

Four years ago, an engine plant of DaimlerChrysler AG initiated an industrial project, which had as a goal to design and implement a production system for large-series aggregate manufacturing that is more flexible and more robust than existing transfer lines. For the control of the newly designed flexible material flow system, the project considered to use an agent-based approach. In intensive cooperation, the DaimlerChrysler plant, external control suppliers, and the DaimlerChrysler research unit developed an agent-based approach for the control of the flexible material flow, showed its potential for improvement in simulation, demonstrated the technical feasibility with the help of a physical demonstrator, and implemented a prototype that was tested as a by-pass to an existing transfer line for cylinder heads and finally analyzed by the plant with respect to its profitability. This paper reports - from the point of view of the research unit - on the development steps necessary to implement the new production system. It is argued that the successful transfer of agent-oriented research results into a production environment requires several steps. In particular, the transfer is only successful if all units affected are integrated into the development process, if the technical feasibility is shown with the help of a physical demonstrator, and if the project provides a profitability analysis comparing existing and new technology. The goal of this paper is to motivate more research concerning agents in production and, based on the experience made, to highlight the critical factors for a successful transfer of agent-oriented research results.

Object-oriented modelling of material flow controls

For a number of years, software design has featured methods of software engineering. Object-oriented modelling (OOM) is a new and very promising method for the professional production of software. This paper aims to contribute to the application of the OOM in planning and deals with the implementation of controls for flexible automated material flow systems. The method of application of the OOM to the design of automatic systems is systematically approached. The introduction provides an overview of the planning process and the history of modelling methods. This is followed by a demonstration of how OOM and its components, `object-oriented analysis', `design' and `programming', can contribute to the handling of the complex demands of a flexible material flow system (I. Wache, Selbstorganisierende Materialflußsteuerung für die flexible Fertigung, in: Tagungsband The International Workshop on Machine Dynamics and Production Automation, April 20–22, 1995 Szcecin, Poland, 18 S; H.-J. Warnecke, Revolution der Unternehmenskultur: Das Fraktale Unternehmen, Springer, Berlin, 1993, 282 S.) The example of a control for the flow of material in an automated pallet transportation system proves the feasibility of the methodology. The pallet transportation system is described in detail in I. Wache, Das Materialfluβsystem `Kugelpalette' für die flexible Fertigung, in: Wissenschaftliche Zeitschrift des Instituts für Fabriksysteme und Logistik, Universität Rostock, Institut für Fabriksysteme und Logistik, 1994, 11 S.