In Part 3, we saw that the differences between business IT and shop floor IT can be reconciled. But in the middle of this reconciliation lie manufacturing execution systems (MES), the link between the shop floor and the top floor. As such, MES includes a wide range of applications that is often daunting at first glance and even more overwhelming after careful scrutiny. Yet, these are functions that every manufacturing company performs on a daily basis because there is no way of doing business without them. Because of this complexity, it is no wonder that many companies regard the automation of their MES processes with more than a little apprehension.
But this need not be so.
Firstly, what is MES? The MESA International definition published in 1997 states:
* Manufacturing execution systems deliver information that enables the optimisation of production activities from order launch to finished goods.
* Using current and accurate data, MES guides, initiates, responds to and reports on plant activities as they occur.
* The resulting rapid response to changing conditions, coupled with a focus on reducing non value-added activities, drives effective plant operations and processes.
* MES improves the return on operational assets as well as on-time delivery, inventory turnarounds, gross margin and cash flow performance.
* MES provides mission-critical information about production activities across the enterprise and supply chain via bi-directional communications.
Today there are many vendors that claim to sell MES solutions, either packaged or in the form of a toolbox. But the variety of applications multiplied by the specific, individual and changing needs of each and every manufacturing company, means that a single, shrink-wrapped package that is all things to all companies is not only unrealistic but would also cost a great deal more than the proverbial arm and leg. With MES, one size definitely does not fit all companies.
So, manufacturers have started to adopt MES solutions as and when they need them but, in most cases, this has meant ending up with disparate and proprietary solutions from a variety of vendors. What was needed was a standard that would eliminate the disparities between various vendor solutions while still giving manufacturers the choice of buying the solutions that best suited their needs.
The ISA-95 standard was developed with the objective of providing standard terminology and object models for information exchange. It continues to be developed and refined by the Instrumentation, Systems and Automation Society (ISA) in collaboration with major vendors of ERP and MES solutions around the world. B2MML (Business To Manufacturing Markup Language) is an XML implementation of the ISA-95 standard by the World Batch Forum (WBF). B2MML has been adopted by players such as SAP and Wonderware and is a defined schema with the objective of reducing the cost, risk and errors associated with implementing interfaces between enterprise and production control systems.
ISA-95 benefits include:
* Adding clarity and common understanding of operations management:
* between suppliers and users for acquisition based on functionality.
* between suppliers and users for common performance expectations and measurable results.
* between suppliers for integration.
* inside companies for a common understanding of operations.
* reducing TCO in every phase of the application life-cycle and provides a basis for continuous improvement.
* increasing simplicity, certainty, reliability and reducing risk and implementation cost.
* extending the life-cycle of applications and preserving capital investment.
* providing a foundation for the use of best practices.
* shaping the integration of various applications.
Nevertheless, ISA-95 does not prescribe solutions. It simply creates an environment for collaboration not only between MES applications but also between the automation, MES and ERP layers.
Based on what we know today, the promise that MES will deliver business value is sound. However, the first question to ask is: "What is driving the need for MES in my business?" This requires a good knowledge of how the business currently runs and where improvements can be made through the deployment of technology. Surprisingly, in many cases the low-lying fruit can be reached without complex solutions and huge IT spending. This will, however, depend on what systems are already in place and how easily (or feasibly) they can contribute to the required solution.
Like any structure the complexity and success of MES often depends on the foundation that it is built on. This foundation can, for example, include IP investment as well as an accurate requirements specification and a business value proposition. The foundation must also include the technology framework that is in place both in the office and on the shopfloor and an accurate estimate of the total cost of ownership (TCO) of an MES implementation and what it takes to make it a success.
Today, there are more than a few examples, in the South African manufacturing landscape, of companies who embraced MES wholeheartedly only to find themselves stranded a year or two down the road because of unforeseen costs, delays and the inability of the systems to keep up with their changing needs. One end-user commented that, unlike with process automation systems, the definition of MES functionality is somewhat vague and it is only after one has got it up and running that one realises what should be in place - but by then, of course, it is too late. One could spend an inordinate amount of time and money defining MES workflows only to have them change six months later. Even the act of automating MES functionality makes one think about other possibilities which inevitably result in specification changes. A more rational approach that would probably halve implementation time and cost is to implement MES bit by bit by making conscious technology investments aimed at achieving medium term business benefits. This would keep functionality far more current and meaningful than the 'Big Bang' approach and give the organisation the agility it needs to win more business and optimise return on assets.
Figure 3 shows three types of approaches to projects. Project 'Red', (bottom of the chart), took so long in its implementation that scrapping it is the nearest its owner will get to a decent ROI.
Project 'Blue' took a significant time to develop and yielded proportionately significant results. However, much of its functionality was lost because it was developed to conform to specifications that have since changed. So there is likely to be yet another lengthy and costly development cycle for project 'Blue'. By perseverance and money alone, it will eventually get there. Then comes the trick of staying there.
Project 'Green', on the other hand, along with its companions, took very little time to define and complete, yielding proportional functionality and ROI. It involved little risk, could be redefined and redone without raising corporate hell if necessary and was exactly what the enterprise needed at that time. The shaded area indicates the ROI difference between fragmented and monolithic approaches to solution implementation.
Projects that run over time or over budget are often doomed to never achieving their full potential or, even worse, to sudden termination. Some companies may even prescribe to 'asset sweating', which typically results in a huge loss of opportunity given how effectively the time, effort and money could have been otherwise utilised.
An important factor to consider in any initiative that will tend to reshape the company's modus operandi (such as the implementation of MES) is the maturity level of the company's major infrastructure components.
Figure 4(a) shows major differences between these various components with the result that components that interact with others may be difficult to implement until these differences are reconciled (the interaction of components cannot be helped since they are all in the same company). Figure 4(b), on the other hand, shows a better maturity alignment between the major components which will greatly simplify the implementation of initiatives like MES.
Today there is much talk about the next level of integration through a unified architecture known as service-oriented architecture (SOA) (first described by Gartner in 1996). This is an integration of company functions rather than products and is defined as; 'a well-factored portfolio of network addressable services'. SOA will be an infrastructure for 'plug-in' business functions such as HR, production management, etc. It is no mere coincidence that Wonderware already has such an infrastructure for the process automation environment known as ArchestrA. SOA also highlights the trend for companies to become more unified in their operations and underscores the importance of the above maturity model.
Conclusion
What is needed today for the successful implementation of MES, is a technology and approach that:
* Allows users to build applications that solve today's problems.
* Is adaptable to change as the company's operational requirements.
* Allows applications to be developed in a managed fashion providing for re-use of engineering effort and low TCO.
* Partners with solution suppliers that have a strong 5-10 year strategy based on leading technology, standards and user requirement trends (eg, infrastructure development, SOA, etc).
* Does not negatively impact on the performance of the business (or state-of-mind of the staff).
* Recognises the maturity differences in the infrastructure components of the organisation.
* Leverages existing IT investments - why use proprietary reporting or specialist historians that do not make use of Microsoft MS SQL or other pervasive database technologies?
The ideal MES implementation allows the company to purchase solutions and grow as required, delivers immediate business value and ROI and allows users to roll out solutions that address defined strategies. An EMS implementation is most successful when it is done within a company infrastructure whose principal components are at the same level of maturity.
In Part 5, we look at performance measurement and management at every level of the enterprise. It is not only production processes that need measurement and control and what is good for the goose is good for the gander.
For more information contact Justin Tweedie, Futuristix, 0861 WONDER (0861 966 337), [email protected] or [email protected]
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