Fieldbus Systems Research Articles

Client server‐based distributed architecture for concurrent design of DCS networks: a case study

Traditional network management tools (NMT) are centralised in nature, as a result of which they are not flexible enough when large control network (e.g. SCADA network) design is desired for. In this paper conventional NMTs have been segmented into components with unified and dedicated functions. Each component has been configured as a client with regard to a central database (i.e. server). The components co‐operate with other components. The work includes the design of flexible NMTs in terms of advanced software architecture for the management of control networks. Three software components (Installation, Configuration and Testing) based on CS architecture and object‐oriented philosophy have been developed. The components are realised with LON™ (Local Operating Network) platform; a proprietary fieldbus system from Echelon, Microsoft’s Visual Basic‐4 platform and Microsoft’s Windows98 operating system. LON Component Architecture Object Server (LCAOS) serves as the network kernel in this design. The configurable components can be used concurrently for the design of control networks.

New TM Robotics fieldbus systems get connected

New TM Robotics fieldbus systems get connected

フィールドバス導入の現状と課題

FOUNDATION Fieldbus was announced as “one of the greatest technological innovation to the next generation”. In Japan, FOUNDATION Fieldbus Association was established in 1994, and standard application products have been released since 1996.Numbers of industrial plants using the Fieldbus system started their operation in 1999, and also in Fushiki Mill, since “N-DIP modernize construction” had been authorized in October 2000, we started to investigate the system. The investigation was on these three points : 1. Flexibility to extended industrial plants (= high leveled adaptation), 2. Product repletion (= PID control function built in Fieldbus products) 3. Integereation with DCS system (= possibility through engineering from DCS system). Then, technical training, designing, engineering, field test, and all kinds of simulation had been enforced, and finally we have succeeded to operate the system in April 15 th 2001. Now, I would like to report the present condition and issues of “New Fieldbus System”.

ANALYSIS AND HEURISTIC SCHEDULING FOR PERIODIC MESSAGES IN FF SYSTEM

The remote periodic message not only has timing constraints but also often has precedence constrains in Foundation Fieldbus system. In this paper, analysis and heuristic scheduling for remote periodic messages are proposed. Firstly, precedence constrains are considered and described by modifying release times and deadlines of remote periodic messages. Secondly, a heuristic algorithm for building FF schedule time list is proposed to find acceptable scheduling solutions by some simple strategies in order to meet these messages' timing constraints. Finally, an example of application shows the process of building FF schedule time list.

A study on production line automation with LonWorks™ control networks

Industrial automation systems look forward to implement new generation of control architecture in response to high flexibility and productivity. Control system users are now keen to promote the emergence of digital technology (DT) in place of 4–20-mA analogue systems. The trend is to implement DT-based distributed control systems (DCS) solution. DCS is becoming very popular because of its own advantages over the whole operating system. A case study in the context of realizing production line automation with DT and DCS philosophy has been presented in this paper. Emphasis has been given on the use of “Fieldbus technology: a digital control networking system”. In this study, Echelon's Local Operating Network (LON) fieldbus system was used because of availability of a wide range of products. A system was integrated with sensors, microswitches and a drive, while a pick-and-place robotic workstation was selected as the representative target platform.

SEU tests performed on the digital communication system for LHC cryogenic instrumentation

The future LHC particle accelerator will use a large number of cryogenic sensors and actuators, most of which are located inside the machine tunnel and therefore in a radiation environment. These elements will communicate through a fieldbus. This paper reports the irradiation study carried out on WorldFIP fieldbus communication system. A digital communication system based on WorldFIP fieldbus protocol has been implemented and single event effects and total ionizing dose radiation tests have been performed on it.

A New Method to Build the FF Schedule Time List

In a single segment Foundation Fieldbus system, a link active scheduler, according to a pre-defined schedule time list, controls all remote periodic message transfers between different field devices on bus. The remote periodic message not only has time constraints but also often has precedence constrains. In this paper a new method to build the schedule time list is proposed, in which both time constraints and precedence constrains are considered and described by modifying release time and deadline. The method proposed is based on slack time monotonic and local search. An example of application shows the process of building FF schedule time list.

Feature Focus: Fieldbus Architecture: A Tale of Two Buses

This article focuses on field bus technology, a digital two-way conul1unications protocol. It is designed to take advantage of intelligent instrumentation equipped with microprocessors to communicate between the field and the control room. Because it can communicate large quantities of data from the field devices, industrial networks tying together field bus instruments open the way for complex control and automation tasks. As field bus evolves, some think that computer networking will play an increasingly important role and improve the performance in the plant. Both Profibus and Fieldbus Foundation provide for Ethernet capability. Wireless communication is also likely to play a potential role in field bus systems. There is a potential for wireless in data acquisition. Issues still needed to be worked out: electrical storms can interfere with communications and wires must be strung to power the devices.

Sensors in Intelligent Buildings

We've all heard of `sick-building' syndrome and the misery this can inflict in the workplace in terms of poor health and lost production. The notion of the Intelligent Building is the modern civil engineer's Big Idea in tackling these and other such deficiencies. The intelligent building can adapt itself to maintain an optimized environment. This ability relies on sensors as a front-line technology - the subject of this volume. Gassmann and Meixner tackle the subject matter by using five categories of intelligent building technology: energy and HVAC (heating, ventilation and air conditioning), information and transportation, safety and security, maintenance, and facility management. These categories of home and building technology are intended to encompass domestic as well as workplace and public environments, but as the introduction states, the breakthrough into the domestic market is not quite here yet. They have targeted, successfully in this reviewer's opinion, the researcher and designer in the field who has his or her own specific interest in sensor issues. Each section of the book contains a number of articles contributed from predominantly European, particularly German and Swiss, research institutions. They cover subjects as diverse as inflatable buildings and a combination of a sensing chair and sensing floor that allows the exact interaction of a human user with his/her immediate surroundings to be integrated within an information system. A fascinating item on biometric access security systems brings to life the `spy-thriller' world of automatic iris and fingerprint scanners as a means of secure access to key-less buildings. The discussion extends to threats to such systems whereby `replay' attacks, for example presenting a face recognition system with a photograph of an individual, reveal the necessary further steps if the technology is to be considered safe. Inevitably though, it is the massive strides in communications and processing technology that are visible in the contributions to this volume that point to where most of the advances will come. The massive interconnection issue of numerous sensors, the `nervous system' of the building is approached in items covering the complexities of fieldbus systems and the use of `wireless' in-building networks. This well presented volume with good quality illustration ends in an investigation of system technologies for the automated home of the near future. Presence-controlled heating and air-conditioning, telemonitoring of the sick or elderly, gas and fire detection and of course a high data rate communication backbone to link everything: all these could feature in the future household. We shall see. Peter Foote

Fault tolerance in Interbus-S standard

The paper deals with the fault tolerance in the Interbus-S, one of the most used FieldBus communication systems. Industrial environments are often featured by critical processes to be controlled. For this reason, the use of a FieldBus to convey information on which these processes are based, requires the presence of fault tolerance mechanisms able to recover a fault in the communication system on its occurrence. In the paper, the authors will highlight the vulnerability of the Interbus-S to fault occurrence in a particular communication node, the Master, foreseen by the Interbus-S standard to distribute the available bandwidth to the control devices connected to the communication system. Finally, the authors will present a protocol extension that allows the whole communication system to continue working after the occurrence of a fault in the Master. The main feature of the proposal is its full compatibility with the Interbus-S standard, as it will be shown in the paper.

Conception and Implementation of an Object Request Broker for the Integration of the Process Level in Manufacturing Systems

In order to be able to react quickly to altering production states, planning tools such as Manufacturing Resource Planning and Enterprise Resource Planning heavily rely on up to date information about the process itself. Thus, access to process level data is one of the most important issues within the production industry. However, the process level lacks support for open, connective communication systems as the number of incompatible fieldbus systems shows. Current solutions, e.g., OLE for Process Control, only focus on a unified interface to the process level, but do not allow to access the functionality of a field device directly. The approach presented in this paper introduces FIMO, the Fieldbus Messaging Object Request Broker, to be deployed in field devices and utilizing the existing fieldbus protocols. With the use of FIMO, devices connected to a fieldbus can be seamlessly integrated in the whole manufacturing hierarchy. The paper gives a brief overview of thestate of the art for accessing process level data. Then, the FIMO architecture is presented in detail including its core services and the mapping of the communication services to the underlying fieldbus system.

Expectation of FOUNDATION Fieldbus

Foundation Fieldbus (hereinafter, referred to as Fieldbus) is a two-way and all digital communication method. It is expected to be the main communication method for the next generation field networks. In 1996, its first specification was released. Since then, many vendors developed all kinds of compatible devices and the test of corresponding devices has been carried out in a trail plant. In 1999, the Fieldbus systems were actually applied in a good many plants in the world. The application of the fieldbus systems will be greatly widened in the year of 2000.

Fieldbus-internet connectivity: the SNMP approach

Important reasons for connecting fieldbus systems to IP-based networks are the provision of remote access for monitoring and maintenance purposes, but also the inclusion of automation systems into an enterprise-wide management scope. Existing solutions are chiefly based on Web technology or require specialized, fieldbus-dependent tools. In this paper, the authors propose a different strategy using the standardized and widely used Simple Network Management Protocol. This approach is largely fieldbus-independent and, at the same time, interoperable with existing LAN technology. They discuss the architecture of a protocol conversion gateway and present a modular approach to cope with the variety of available fieldbus protocols. They further propose a structure for a management information base suitable to represent the fieldbus data objects. By means of prototype implementations for different fieldbus systems (Profibus, P-NET, and EIB), they study the influence of the underlying fieldbus communication principles on the gateway implementation and operation.

How to Teach Topics of Modern Control Systems to Computer Science Students?

Teaching principles of process control engineering to computer science students is an enjoyable but also exhaustive task. In order to run a lecture with an associated practical dedicated to modern control systems for approximately 200 students with acceptable effort, it must be organized carefully and strictly. This article surveys our experiences and efforts regarding the setup of a new practical. We present its contents and give a first outlook on our new equipment based upon fieldbus systems. Finally, we describe some principal issues in question when organizing our next generation computer science practical.

A fieldbus for machine safety

The detection of dangerous failures of the fieldbus system is of paramount importance. In this paper, the author explains how machine safety systems can benefit from fieldbus technology.

STPN Model of Physical and MAC Layer of Lon Works®

LonWorks is one of the most popular fieldbus systems in building automation. It uses a MAC protocol called ‘predictive p-persistent CSMA’, which differentiates from p-persistent CSMA method by partial prediction of the channel backlog. Under optimal conditions predictive p-persistent CSMA keeps collision rate independent of the channel utilisation. | Stochastic Timed Petri Net Model of LONWORKS MAC layer and small PN extension for linking of models are presented. Some simulation results are demonstrated.

A closer look into Internet-fieldbus connectivity

The use of IP-based networks as a convenient means to remotely access fieldbus systems is a hot topic and will become more and more widespread in the near future. In this article, we shall explore possibilities to achieve this goal and discuss the basic requirements for such an interconnection. Particular emphasis will be put on the architectural shortcomings of existing approaches and on emerging security issues.

Smart components-based servo pneumatic actuation systems

Pneumatic drives are the most widely used form of industrial actuation system. However, research in relevant areas is very limited, often carried out, if at all, in isolated environments. There is a lack of strategic thinking and tools, which can enable developments to go forward in an efficient manner. In recognising the advancements in PC-technology, fieldbus systems, microprocessors and computing technologies, the authors advocate the concept of smart components-based servo pneumatic actuation systems. The paper expands on the components-based nature of pneumatic drive systems to identify design templates for smart valves, smart sensors, smart actuators, etc. The development of components-based pneumatic drive systems is considered in the context of a recently completed UK EPSRC funded research project on high speed servo-pneumatic actuation, addressing issues such as simulation tools, algorithm development, sizing, tuning, installation and commissioning. A high speed pneumatically-driven gantry pick-and-place handling system with novel design features is presented to demonstrate the capability and attributes of pneumatic drives for more sophisticated applications.

Free Programmable Fieldbus Interface

Free programmable fieldbus controller the IX1 is presented in the contribution. It consists of a 12-Bit 24 MIPS processor, integrated data and program memory, a configurable serial fieldbus interface and a flexible user port all on one chip. The controller has been designed to serve as a programmable serial controller with an emphasis on fieldbus systems. In the contribution there is also described single components ofthe controller as well as an industrial application ofthe microcontroller system.

Locally distributed automation – but with which fieldbus system?

Discusses the distribution of application functions to process‐oriented field devices and process‐remote components in distributed automation systems. Describes the use of fieldbus systems, function block technology based on standardised function blocks and a suitable infrastructure to enable these function blocks to cooperate during run time.