Contract Based Verification of IEC 61499

14th International Conference on Industrial Informatics (INDIN 2016). 18 to 21, Jul, 2016, Factory Automation. Poitiers, France.The IEC 61499 standard proposes an event driven execution model for component based (in terms of Function Blocks), distributed industrial automation applications. However, the standard provides only an informal execution semantics, thusin consequence behavior and correctness relies on the design decisions made by the tool vendor. In this paper we present the formalization of a subset of the IEC 61499 standard in order to provide an underpinning for the static verification of Function Block models by means of deductive reasoning. Specifically, we contribute by addressing verification at the component,algorithm, and ECC levels. From Function Block descriptions, enrichedwith formal contracts, we show that correctness of component compositions, as well as functional and transitional behavior can be ensured. Feasibility of the approach is demonstrated by manually encoding a set of representative use-cases in WhyML,for which the verification conditions are automatically derived (through the Why3 platform) and discharged (using automaticSMT-based solvers). Furthermore, we discuss opportunities and challenges towards deriving certified executables for IEC 61499 models.info:eu-repo/semantics/publishedVersio

Reconciling a component and process view

In many cases we need to represent on the same abstraction level not only system components but also processes within the system, and if for both representation different frameworks are used, the system model becomes hard to read and to understand. We suggest a solution how to cover this gap and to reconcile component and process views on system representation: a formal framework that gives the advantage of solving design problems for large-scale component systems.Comment: Preprint, 7th International Workshop on Modeling in Software Engineering (MiSE) at ICSE 201

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

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

A system development methodology for embedded applications

In recent years, Singapore’s manufacturing sector has contributed more than a quarter of the total Gross Domestic Product (GDP) and has established global leadership positions in several manufacturing areas such as electronics, Information Technology (IT) and industrial automation. The Singapore Economic Review Committee (ERC) recommendation states that “software and embedded systems that drive products are one of the most important technologies for the manufacturing sector. “ With the increasing adoption of automated and intelligent products, embedded systems have emerged as a crucial technology for Singapore. However, the development of embedded applications is not a trivial undertaking as it can usually involve multi-discipline parties and different application platforms. Most embedded application developments use either vendor specific or desktop based methodologies. Vendor specific methodologies constrain the company to rely on the specific vendor's solutions, whereas desktop-based methodologies are not well suited to embedded application development. Therefore, this research aims to develop a standard-based system development methodology for embedded applications. The research programme comprises 5 stages. The first stage reviews the existing system development methodologies for embedded applications. The next stage formulates the proposed conceptual methodology followed by the development of the proof-of-concept tool to demonstrate the merits of the proposed approach. The methodology is then tested and evaluated respectively by using industrial experiments and feedback from a workshop. The final stage refines the methodology based on the feedback and presents the final system development methodology. The research has provided a sound foundation which future research in methodology for embedded applications to develop further.Eng

A Distributed-Ledger, Edge-Computing Architecture for Automation and Computer Integration in Semiconductor Manufacturing

Contemporary 300mm semiconductor manufacturing systems have highly automated and digitalized cyber-physical integration. They suffer from the profound problems of integrating large, centralized legacy systems with small islands of automation. With the recent advances in disruptive technologies, semiconductor manufacturing has faced dramatic pressures to reengineer its automation and computer integrated systems. This paper proposes a Distributed- Ledger, Edge-Computing Architecture (DLECA) for automation and computer integration in semiconductor manufacturing. Based on distributed ledger and edge computing technologies, DLECA establishes a decentralized software framework where manufacturing data are stored in distributed ledgers and processed locally by executing smart contracts at the edge nodes. We adopt an important topic of automation and computer integration for semiconductor research & development (R&D) operations as the study vehicle to illustrate the operational structure and functionality, applications, and feasibility of the proposed DLECA software framewor

A system development methodology for embedded applications

In recent years, Singapore’s manufacturing sector has contributed more than a quarter of the total Gross Domestic Product (GDP) and has established global leadership positions in several manufacturing areas such as electronics, Information Technology (IT) and industrial automation. The Singapore Economic Review Committee (ERC) recommendation states that “software and embedded systems that drive products are one of the most important technologies for the manufacturing sector. “ With the increasing adoption of automated and intelligent products, embedded systems have emerged as a crucial technology for Singapore. However, the development of embedded applications is not a trivial undertaking as it can usually involve multi-discipline parties and different application platforms. Most embedded application developments use either vendor specific or desktop based methodologies. Vendor specific methodologies constrain the company to rely on the specific vendor's solutions, whereas desktop-based methodologies are not well suited to embedded application development. Therefore, this research aims to develop a standard-based system development methodology for embedded applications. The research programme comprises 5 stages. The first stage reviews the existing system development methodologies for embedded applications. The next stage formulates the proposed conceptual methodology followed by the development of the proof-of-concept tool to demonstrate the merits of the proposed approach. The methodology is then tested and evaluated respectively by using industrial experiments and feedback from a workshop. The final stage refines the methodology based on the feedback and presents the final system development methodology. The research has provided a sound foundation which future research in methodology for embedded applications to develop further.Eng

Component-based modeling and observer-based verification for railway safety-critical applications

1th International Symposium on Formal Aspects of Component Software , Bertinoro, Italie, 10-/09/2014 - 12/09/2015International audienceOne of the challenges that engineers face, during the development process of safety-critical systems, is the verification of safety application models before implementation. Formalization is important in order to verify that the design meets the specified safety requirements. In this paper, we formally describe the set of transformation rules, which are defined for the automatic transformation of safety application source models to timed automata target models. The source models are based on our domain-specific component model, named SARA, dedicated to SAfety-critical RAilway control applications. The target models are then used for the observer-based verification of safety requirements. This method provides an intuitive way of expressing system properties without requiring a significant knowledge of higher order logic and theorem proving, as required in most of existing approaches. An experimentation over a chosen benchmark at rail-road crossing protection application is shown to highlight the proposed approach