2,828 research outputs found

    A Novel Method for Adaptive Control of Manufacturing Equipment in Cloud Environments

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    The ability to adaptively control manufacturing equipment, both in local and distributed environments, is becoming increasingly more important for many manufacturing companies. One important reason for this is that manufacturing companies are facing increasing levels of changes, variations and uncertainty, caused by both internal and external factors, which can negatively impact their performance. Frequently changing consumer requirements and market demands usually lead to variations in manufacturing quantities, product design and shorter product life-cycles. Variations in manufacturing capability and functionality, such as equipment breakdowns, missing/worn/broken tools and delays, also contribute to a high level of uncertainty. The result is unpredictable manufacturing system performance, with an increased number of unforeseen events occurring in these systems. Events which are difficult for traditional planning and control systems to satisfactorily manage. For manufacturing scenarios such as these, the use of real-time manufacturing information and intelligence is necessary to enable manufacturing activities to be performed according to actual manufacturing conditions and requirements, and not according to a pre-determined process plan. Therefore, there is a need for an event-driven control approach to facilitate adaptive decision-making and dynamic control capabilities. Another reason driving the move for adaptive control of manufacturing equipment is the trend of increasing globalization, which forces manufacturing industry to focus on more cost-effective manufacturing systems and collaboration within global supply chains and manufacturing networks. Cloud Manufacturing is evolving as a new manufacturing paradigm to match this trend, enabling the mutually advantageous sharing of resources, knowledge and information between distributed companies and manufacturing units. One of the crucial objectives for Cloud Manufacturing is the coordinated planning, control and execution of discrete manufacturing operations in collaborative and networked environments. Therefore, there is also a need that such an event-driven control approach supports the control of distributed manufacturing equipment. The aim of this research study is to define and verify a novel and comprehensive method for adaptive control of manufacturing equipment in cloud environments. The presented research follows the Design Science Research methodology. From a review of research literature, problems regarding adaptive manufacturing equipment control have been identified. A control approach, building on a structure of event-driven Manufacturing Feature Function Blocks, supported by an Information Framework, has been formulated. The Function Block structure is constructed to generate real-time control instructions, triggered by events from the manufacturing environment. The Information Framework uses the concept of Ontologies and The Semantic Web to enable description and matching of manufacturing resource capabilities and manufacturing task requests in distributed environments, e.g. within Cloud Manufacturing. The suggested control approach has been designed and instantiated, implemented as prototype systems for both local and distributed manufacturing scenarios, in both real and virtual applications. In these systems, event-driven Assembly Feature Function Blocks for adaptive control of robotic assembly tasks have been used to demonstrate the applicability of the control approach. The utility and performance of these prototype systems have been tested, verified and evaluated for different assembly scenarios. The proposed control approach has many promising characteristics for use within both local and distributed environments, such as cloud environments. The biggest advantage compared to traditional control is that the required control is created at run-time according to actual manufacturing conditions. The biggest obstacle for being applicable to its full extent is manufacturing equipment controlled by proprietary control systems, with native control languages. To take the full advantage of the IEC Function Block control approach, controllers which can interface, interpret and execute these Function Blocks directly, are necessary

    An architecture to integrate IEC 61131-3 systems in an IEC 61499 distributed solution

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    The IEC 61499 standard has been developed to allow the modeling and design of distributed control systems, providing advanced concepts of software engineering (such as abstraction and encapsulation) to the world of control engineering. The introduction of this standard in already existing control environments poses challenges, since programs written using the widespread IEC 61131-3 programming standard cannot be directly executed in a fully IEC 61499 environment without reengineering effort. In order to solve this problem, this paper presents an architecture to integrate modules of the two standards, allowing the exploitation of the benefits of both. The proposed architecture is based on the coexistence of control software of the two standards. Modules written in one standard interact with some particular interfaces that encapsulate functionalities and information to be exchanged with the other standard. In particular, the architecture permits to utilize available run-times without modification, it allows the reuse of software modules, and it utilizes existing features of the standards. A methodology to integrate IEC 61131-3 modules in an IEC 61499 distributed solution based on such architecture is also developed, and it is described via a case study to prove feasibility and benefits. Experimental results demonstrate that the proposed solution does not add substantial load or delays to the system when compared to an IEC 61131-3 based solution. By acting on task period, it can achieve performances similar to an IEC 61499 solution

    On cost-effective reuse of components in the design of complex reconfigurable systems

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    Design strategies that benefit from the reuse of system components can reduce costs while maintaining or increasing dependability—we use the term dependability to tie together reliability and availability. D3H2 (aDaptive Dependable Design for systems with Homogeneous and Heterogeneous redundancies) is a methodology that supports the design of complex systems with a focus on reconfiguration and component reuse. D3H2 systematizes the identification of heterogeneous redundancies and optimizes the design of fault detection and reconfiguration mechanisms, by enabling the analysis of design alternatives with respect to dependability and cost. In this paper, we extend D3H2 for application to repairable systems. The method is extended with analysis capabilities allowing dependability assessment of complex reconfigurable systems. Analysed scenarios include time-dependencies between failure events and the corresponding reconfiguration actions. We demonstrate how D3H2 can support decisions about fault detection and reconfiguration that seek to improve dependability while reducing costs via application to a realistic railway case study

    RTLabOS Dissemination Activities:RTLabOS D4.2

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    Engineering methods and tools for cyber–physical automation systems

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    Much has been published about potential benefits of the adoption of cyber–physical systems (CPSs) in manufacturing industry. However, less has been said about how such automation systems might be effectively configured and supported through their lifecycles and how application modeling, visualization, and reuse of such systems might be best achieved. It is vitally important to be able to incorporate support for engineering best practice while at the same time exploiting the potential that CPS has to offer in an automation systems setting. This paper considers the industrial context for the engineering of CPS. It reviews engineering approaches that have been proposed or adopted to date including Industry 4.0 and provides examples of engineering methods and tools that are currently available. The paper then focuses on the CPS engineering toolset being developed by the Automation Systems Group (ASG) in the Warwick Manufacturing Group (WMG), University of Warwick, Coventry, U.K. and explains via an industrial case study how such a component-based engineering toolset can support an integrated approach to the virtual and physical engineering of automation systems through their lifecycle via a method that enables multiple vendors' equipment to be effectively integrated and provides support for the specification, validation, and use of such systems across the supply chain, e.g., between end users and system integrators

    Engineering framework for service-oriented automation systems

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    Tese de doutoramento. Engenharia Informática. Universidade do Porto. Faculdade de Engenharia. 201

    Distributed implementation of Grafcets through IEC 61499

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    Comunicación presentada en 25th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA), 2020A Grafcet is a standardized model for describing the behavior of systems which is popular among automation engineers. As the Grafcet standard excludes implementation details, the models are typically translated to automation software. Such software was traditionally programmed in one of the languages specified in IEC 61131-3. Nowadays, automation software is increasingly modelled in IEC 61499 which facilitates designing distributed control systems. In this paper, we define a standardized translation methodology, so that automation engineers can benefit from the advantages of IEC 61499 while continuing to use Grafcet. We discuss the differences between Grafcet and IEC 61499. We translated a Grafcet model into an IEC 61499 application to illustrate the process and derive guidelines for application designers. For the core concepts of Grafcet, we present the corresponding structure in IEC 61499
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