A new agents-based model for dynamic job allocation in manufacturing shopfloors

Market-based mechanisms such as the contract net protocol (CNP) are very popular for dynamic job allocation in distributed manufacturing control and scheduling. The CNP can be deployed with different configurations of the system elements. Every configuration corresponds to a basic or a hybrid topology. The subject of topology is generally discussed in the field of “distributed systems.” Inspired from the notion of topology in the distributed systems, this paper proposes a ring-like model as a competitor for the web-like CNP-based job allocation within the concept of holonic manufacturing systems. Details of the algorithm for scheduling and assignment of jobs to resources in the ring structure is presented and its performance is compared with both CNP-based distributed model, and the centralized conventional scheduling of a real manufacturing case study involving a major turbine production plant. Comparison of performance indicators such as time and cost of operations shows that the distributed models clearly outperform the conventional practice with meaningful impact on the production economy. As a possible implementation strategy, a hybrid switching model, composed of both competing models, is proposed

Software for integrated manufacturing systems, part 2

Part 1 presented an overview of the unified approach to manufacturing software. The specific characteristics of the approach that allow it to realize the goals of reduced cost, increased reliability and increased flexibility are considered. Why the blending of a components view, distributed languages, generics and formal models is important, why each individual part of this approach is essential, and why each component will typically have each of these parts are examined. An example of a specification for a real material handling system is presented using the approach and compared with the standard interface specification given by the manufacturer. Use of the component in a distributed manufacturing system is then compared with use of the traditional specification with a more traditional approach to designing the system. An overview is also provided of the underlying mechanisms used for implementing distributed manufacturing systems using the unified software/hardware component approach

A framework for distributed manufacturing applications

The new organisational structures used in world wide manufacturing systems require the development of distributed applications, which present solutions to their requirements. The work research in the distributed manufacturing control leads to emergent paradigms, such as Holonic Manufacturing Systems (HMS) and Bionic Manufacturing Systems (BMS), which translates the concepts from social organisations and biological systems to the manufacturing world. This paper present a Framework for the development of distributed manufacturing applications, based in an agent-based architecture, which implements some Holonic and Bionic Manufacturing Systems concepts

A Product Life Cycle Ontology for Additive Manufacturing

The manufacturing industry is evolving rapidly, becoming more complex, more interconnected, and more geographically distributed. Competitive pressure and diversity of consumer demand are driving manufacturing companies to rely more and more on improved knowledge management practices. As a result, multiple software systems are being created to support the integration of data across the product life cycle. Unfortunately, these systems manifest a low degree of interoperability, and this creates problems, for instance when different enterprises or different branches of an enterprise interact. Common ontologies (consensus-based controlled vocabularies) have proved themselves in various domains as a valuable tool for solving such problems. In this paper, we present a consensus-based Additive Manufacturing Ontology (AMO) and illustrate its application in promoting re-usability in the field of dentistry product manufacturing

A scalable parallel finite element framework for growing geometries. Application to metal additive manufacturing

This work introduces an innovative parallel, fully-distributed finite element framework for growing geometries and its application to metal additive manufacturing. It is well-known that virtual part design and qualification in additive manufacturing requires highly-accurate multiscale and multiphysics analyses. Only high performance computing tools are able to handle such complexity in time frames compatible with time-to-market. However, efficiency, without loss of accuracy, has rarely held the centre stage in the numerical community. Here, in contrast, the framework is designed to adequately exploit the resources of high-end distributed-memory machines. It is grounded on three building blocks: (1) Hierarchical adaptive mesh refinement with octree-based meshes; (2) a parallel strategy to model the growth of the geometry; (3) state-of-the-art parallel iterative linear solvers. Computational experiments consider the heat transfer analysis at the part scale of the printing process by powder-bed technologies. After verification against a 3D benchmark, a strong-scaling analysis assesses performance and identifies major sources of parallel overhead. A third numerical example examines the efficiency and robustness of (2) in a curved 3D shape. Unprecedented parallelism and scalability were achieved in this work. Hence, this framework contributes to take on higher complexity and/or accuracy, not only of part-scale simulations of metal or polymer additive manufacturing, but also in welding, sedimentation, atherosclerosis, or any other physical problem where the physical domain of interest grows in time

Development of a novel 3D simulation modelling system for distributed manufacturing

This paper describes a novel 3D simulation modelling system for supporting our distributed machine design and control paradigm with respect to simulating and emulating machine behaviour on the Internet. The system has been designed and implemented using Java2D and Java3D. An easy assembly concept of drag-and-drop assembly has been realised and implemented by the introduction of new connection features (unified interface assembly features) between two assembly components (modules). The system comprises a hierarchical geometric modeller, a behavioural editor, and two assemblers. During modelling, designers can combine basic modelling primitives with general extrusions and integrate CAD geometric models into simulation models. Each simulation component (module) model can be visualised and animated in VRML browsers. It is reusable. This makes machine design re-configurable and flexible. A case study example is given to support our conclusions

Modelling very large complex systems using distributed simulation: A pilot study in a healthcare setting

Modern manufacturing supply chains are hugely complex and like all stochastic systems, can benefit from simulation. Unfortunately supply chain systems often result in massively large and complicated models, which even today’s powerful computers cannot run efficiently. This paper presents one possible solution - distributed simulation. This pilot study is implemented in a healthcare setting, the supply chain of blood from donor to recipient

Design and development of a hybrid control system for flexible manufacturing : a thesis presented in partial fulfilment of the requirements for the degree of Master of Technology in Manufacturing and Industrial Technology at Massey University

Irregular Pagination MisnumberedFlexible Manufacturing Systems (FMS) appeared upon the manufacturing scene in the early 1970s, installations presently number in the thousands. However, many current installations in fact lack flexibility, do not operate in real-time and are prohibitively expensive. Therefore there are obvious benefits to be gained from making improvements to existing flexible manufacturing systems. Research conducted for this thesis focused on two major areas. The implementation of the FMS control system on a SCADA package and the development of an auction based scheduling system. This entailed the development of a hybrid control model composed of three distinct layers; factory, cell and intelligent entity. Key portions of both the factory and cell controllers were then implemented so as to create a minimal system. This has been completed to the point where the auction algorithm has been implemented and tested in an appropriate framework. In achieving the goals mentioned above a number of novel design concepts have been utilised. There are two which are most important, these are the use of low cost modules for the construction of a flexible co-operative manufacturing system, and the ability of this system to operate in a physically distributed area via a Local Area Network. Meaning it is inherently adaptable and resistant to failure. These novel design concepts were ingrained throughout the entire three layered control model. It is felt that this research has succeeded in demonstrating the possibility of implementing a FMS control system on a low cost SCADA package using low cost software and computing elements. The ability of the distributed, auction-based approach to operate successfully within this system, has also been demonstrated through simulation

Distributed design of product oriented manufacturing systems

Manufacturing leanness and agility are requirements of today’s manufacturing systems. Leanness call for a best fit of the manufacturing systems to products, therefore requiring product oriented manufacturing systems (POMS). Manufacturing agility can be achieved through easy systems reconfiguration to fit changing manufacturing requirements, which may mean dynamically configuring POMS. For this a suitable design system is required. Due to complexity of this design, and to the need for using suitable design methods, which may not be available locally, distributed sources of design services can be used. This paper presents and describes a prototype of a Distributed Design system for POMS based on a POMS design methodology and distributed suppliers of design services