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The purpose of this paper is to describe how emerging open standards are replacing traditional industrial networks. Current industrial Ethernet networks are not interoperable; thus, limiting the potential capabilities for the Industrial Internet of Things (IIoT). There is no forthcoming new generation fieldbus standard to integrate into the IIoT and Industry 4.0 revolution. The open platform communications unified architecture (OPC UA) time-sensitive networking (TSN) is a potential vendor-independent successor technology for the factory network. The OPC UA is a data exchange standard for industrial communication, and TSN is an Institute of Electrical and Electronics Engineers standard for Ethernet that supports real-time behaviour. The merging of these open standard solutions can facilitate cross-vendor interoperability for Industry 4.0 and IIoT products.

A brief review of the history of the fieldbus standards is presented, which highlights the shortcomings for current industrial systems in meeting converged traffic solutions. An experimental system for the OPC UA TSN is described to demonstrate an approach to developing a three-layer factory network system with an emphasis on the field layer.

From the multitude of existing industrial network schemes, there is a convergence pathway in solutions based on TSN Ethernet and OPC UA. At the field level, basic timing measurements in this paper show that the OPC UA TSN can meet the basic critical timing requirements for a fieldbus network.

This paper uniquely focuses on the specific fieldbus standards elements of industrial networks evolution and traces the developments from the early history to the current developing integration in IIoT context.

The hardware and software development of a remotely controlled hydraulic valve assembly is described. The valve becomes a dedicated server in a distributed control environment. The communication system is an Ethernet network supporting the UDP/IP communications protocol. A client/server application model is developed that allows a client to specify a desired control position for a valve spool. The solution is being proposed as an alternative to a formal fieldbus solution, where precision real‐time operation is not required. The performance of the valve is measured under different configurations considering both open loop and closed loop models. The justification for selecting the UDP/IP protocol is stated. The resulting hydraulic valve control system is efficient, accurate and flexible.

This paper aims to describe the development of a new software tool for the scheduling of real‐time control messages in a time‐triggered control network. The prime application area for such a solution is in real‐time robotic controllers and other similar machine control systems.

The design of a scheduling tool, called SMART‐Plan, is described. The tool is based on a “least slack time” scheduling policy. A prototype tool for the time‐triggered controller area network (TTCAN) is developed. The design is validated against Society of Automotive Engineers Benchmark and a formal verification of the message schedule is also proposed.

The research findings show that it is feasible to develop such a message scheduling tool and the performance of the tool is comparable with other research solutions, which have been applied in the past to simple periodic schedulers, as opposed to time‐triggered networks.

Although the prototype solution assumes a TTCAN control network, the concept will also be feasible for other types of time‐triggered control networks. The availability of such a tool might encourage developers of robotic equipment to adopt the time‐triggered network approach for the architectural development of such control systems. To date, the problems associated with the message scheduling of such time‐triggered systems have been an inhibitor to such developments.

This is a new scheduling approach to the message scheduling of time‐triggerred control networks.

In industrial distributed control environments for automation technology, Ethernet network based solutions are gaining prominence in the traditional fieldbus application areas with the promise of standardised solutions that can support real‐time operation to a resolution of less than 1 μm. However, there are no formal standards for a real‐time Industrial Ethernet. This paper looks at some of the emerging de facto solutions and describes a novel project where clusters of real‐time transducer networks are developed and the control is tightly synchronised using the IEEE 1588 clock synchronisation standard, realising a “Time‐triggered Ethernet” solution.

This paper sets out to highlight the problem associated with the development of fieldbus diagnostics in a multi‐vendor environment and to propose a solution based on diagnostic function blocks (FB).

The work focuses on the “master‐slave” communication model in a PROFIBUS fieldbus system, where three different vendor solutions are investigated.

Although the fieldbus standards specify the type and format of the diagnostics data, the extent, location and sequence of diagnostics data within a controller are entirely vendor‐dependent. The outcome from this work defines a framework for representing the diagnostics data in the context of a special function block.

This research work defines a novel unified framework for representing the fieldbus diagnostics data using FB for multi‐vendor solutions in a PROFIBUS environment.

To emphasise the need for remote fieldbus diagnostics and to show a technical solution based on industry standard approaches.

The design and approach takes a Profibus fieldbus, as an example candidate, and captures the diagnostic data using an OPC model and then uses a Java RMI object broker to develop/support the remote end clients.

The findings show, by an implementation example, that it is possible to implement remote diagnostics for a fieldbus network, without interfering with the operation of the network. The findings also highlight the need for security in such a solution.

The implementation example is rather cumbersome, but the paper suggests that all the hardware and software could be implemented on a single embedded processor in a single box. The security issues are flagged as a possible limitation, but solution approaches are briefly suggested.

The paper highlights the lack of standardisation around fieldbus diagnostics. Even for the same fieldbus type, different manufacturers will use different diagnostic protocols and codes. This paper suggests a practical implementation, where the diagnostic codes can be interpreted a fixed stage and presented to an end client in a consistent manner.

This work is based on a two year original research project. The solution makes heavy use of industry standard protocols but the work is original.

The CAN (Controller Area Network) standard, ISO 11898, is now ubiquitous in industrial automation environments. CAN is used with defined application layers for implementing sensor/actuator level distributed control applications. Protocols such as Honeywell's SDS, ODVA's DeviceNet (Allen Bradley) and CANopen are well‐known device level networks which are based on the CAN protocol. A new time‐triggered protocol for CAN, referred to as TTCAN, is under development where the real‐time scheduling of the network traffic can be formally verified. This paper introduces the new TTCAN protocol and suggests that TTCAN has the potential to provide new solutions in industrial automation applications. TTCAN has the potential to replace some conventional pneumatic, hydraulic and other mechanical safety‐critical control systems with a reliable electronic network. The emergence of 42‐volt technology from the automotive world will further complement the TTCAN technology to provide some unique industrial automation solutions.