874 research outputs found

    CSP channels for CAN-bus connected embedded control systems

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    Closed loop control system typically contains multitude of sensors and actuators operated simultaneously. So they are parallel and distributed in its essence. But when mapping this parallelism to software, lot of obstacles concerning multithreading communication and synchronization issues arise. To overcome this problem, the CT kernel/library based on CSP algebra has been developed. This project (TES.5410) is about developing communication extension to the CT library to make it applicable in distributed systems. Since the library is tailored for control systems, properties and requirements of control systems are taken into special consideration. Applicability of existing middleware solutions is examined. A comparison of applicable fieldbus protocols is done in order to determine most suitable ones and CAN fieldbus is chosen to be first fieldbus used. Brief overview of CSP and existing CSP based libraries is given. Middleware architecture is proposed along with few novel ideas

    Software for Embedded Control Systems

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    The research of our team deals with the realization of control schemes on digital computers. As such the emphasis is on embedded control software implementation. Applications are in the field of mechatronic devices, using a mechatronic design approach (the integrated and optimal design of a mechanical system and its embedded control system). The ultimate goal is to support the application developer (i.e. mechatronic design engineer) such that implementing control software according to Ă°o it the first time rightÂż becomes business as usual

    Real-time and fault tolerance in distributed control software

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    Closed loop control systems typically contain multitude of spatially distributed sensors and actuators operated simultaneously. So those systems are parallel and distributed in their essence. But mapping this parallelism onto the given distributed hardware architecture, brings in some additional requirements: safe multithreading, optimal process allocation, real-time scheduling of bus and network resources. Nowadays, fault tolerance methods and fast even online reconfiguration are becoming increasingly important. All those often conflicting requirements, make design and implementation of real-time distributed control systems an extremely difficult task, that requires substantial knowledge in several areas of control and computer science. Although many design methods have been proposed so far, none of them had succeeded to cover all important aspects of the problem at hand. [1] Continuous increase of production in embedded market, makes a simple and natural design methodology for real-time systems needed more then ever

    Market fields structure & dynamics in industrial automation

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    There is a research tradition in the economics of standards which addresses standards wars, antitrust concerns or positive externalities from standards. Recent research has also dealt with the process characteristics of standardisation, de facto standard-setting consortia and intellectual property concerns in the technology specification or implementation phase. Nonetheless, there are no studies which analyse capabilities, comparative industry dynamics or incentive structures sufficiently in the context of standard-setting. In my study, I address the characteristics of collaborative research and standard-setting as a new mode of deploying assets beyond motivations well-known from R&D consortia or market alliances. On the basis of a case study of a leading user organisation in the market for industrial automation technology, but also a descriptive network analysis of cross-community affiliations, I demonstrate that there must be a paradoxical relationship between cooperation and competition. More precisely, I explain how there can be a dual relationship between value creation and value capture respecting exploration and exploitation. My case study emphasises the dynamics between knowledge stocks (knowledge alignment, narrowing and deepening) produced by collaborative standard setting and innovation; it also sheds light on an evolutional relationship between the exploration of assets and use cases and each firm's exploitation activities in the market. I derive standard-setting capabilities from an empirical analysis of membership structures, policies and incumbent firm characteristics in selected, but leading, user organisations. The results are as follows: the market for industrial automation technology is characterised by collaboration on standards, high technology influences of other industries and network effects on standards. Further, system integrators play a decisive role in value creation in the customer-specific business case. Standard-setting activities appear to be loosely coupled to the products offered on the market. Core leaders in world standards in industrial automation own a variety of assets and they are affiliated to many standard-setting communities rather than exclusively committed to a few standards. Furthermore, their R&D ratios outperform those of peripheral members and experience in standard-setting processes can be assumed. Standard-setting communities specify common core concepts as the basis for the development of each member's proprietary products, complementary technologies and industrial services. From a knowledge-based perspective, the targeted disclosure of certain knowledge can be used to achieve high innovation returns through systemic products which add proprietary features to open standards. Finally, the interplay between exploitation and exploration respecting the deployment of standard-setting capabilities linked to cooperative, pre-competitive processes leads to an evolution in common technology owned and exploited by the standard-setting community as a particular kind of innovation ecosystem. --standard-setting,innovation,industry dynamics and context,industrial automation

    Petri net modeling and performance analysis of can fieldbus

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    The CAN FB (Controller Area Network FieldBus) has been in existence for ten years. It supports automated manufacturing and process control environments to interconnect intelligent devices such as valves, sensors, and actuators. CAN FieldBus has a high bit rate and the ability to detect errors. It is immune to noise and resistant to shock, vibration, and heat. Two recently introduced mechanisms, Distributed Priority Queue (DPQ) and Priority Promotion (PP) enable CAN FieldBus networks to share out the system bandwidth and grant ail upper bound on the transmission times so as to meet the requirements in real-time communications. Modeling and analysis of such networks are an important research area for their wide applications in manufacturing automation. This thesis presents a Petri net methodology which models and analyzes CAN FieldBus access protocol. A Reachability Graph of the Petri net model is -utilized to study the behavioral properties of the protocol. A timed Petri net simulator is used to evaluate the performance of the protocol. Performance measures include the completion time for successful events and operations. Operational parameters investigated using the Petri Net model are FieldBus speed, the length of each frame, and the number of frames in a message

    FOUNDATION FIELDBUS 1NTEROPERABILITY TESTING

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    This report is to discuss about the research and testing of Basic Interoperability Testing for Foundation Fieldbus system. The Foundation Fieldbus is the new protocol that used in the PETRONAS process plant. Since that, PETRONAS personnel get lack of training in handling this new system. Devices that used in Foundation Fieldbus system can not work or interoperate with the devices from different manufacturers. This project is to perform the interoperability testing and the result will be used as the reference for Foundation Ficldbus system for PETRONAS personnel that handling this new system. Besides, the purpose of this project is to find out interoperability devices with the manufacturers system. The methodology towards achieving the objectives includes the theoretical and technical research, and testing the system and devices. Research and understanding of the project is very important. Some procedure needs to follow to get the desired result and accuracy and consistency of the result need to take to the consideration. The specific system need to conduct for the basic interoperability testing is Honeywell system. The tasks that should be done under this Basic Interoperability Test are device commissioning, device decommissioning, online device replacement, physical layer diagnostics, calibration function checks, and online parameter downloads. From this test, all the devices that had been tested were successfully done. The research for the Foundation Ficldbus should continuously perform to improve the system from time to time and the analysis of result and reports will use for a future research

    Foundation fieldbus : from theory to practice

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    This paper describes the main characteristics of the Foundation Fieldbus (FF) technology considering both communication levels, namely H1 and H2, which have bit rates of 31.25 K and 100 Mbit/s, respectively. Several details about the physical layer, communication stack and user layer will be highlighted. Topics related with the configuration of instruments, as well as the design and implementation of supervision software, based on a LabVIEW interface, will be presented. A pilot plant that includes temperature, pressure, level and flow variables will be used to test and validate the capabilities of FF systems. Experimental results will be analyzed, their meaning discussed and the overall performance evaluated
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