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MES Functional Model This model shows the relevant functions of MES and links to other systems. Functions may link in multiple ways by product and need. (Source: MESA International).

MES: Will E-commerce Drive It Into Auto?

MES—manufacturing execution system—is not a common term in automotive manufacturing, but the concept is gaining credibility as the industry responds to supply chain and e-commerce pressures.

General Motors and Ford, even AlliedSignal, have always dealt with a hypothetical composite customer—a "statistical model of someone who may never really exist," asserts Raymond Lipa, COO for BRL & Co. (Ann Arbor, MI).

Now there's a revolutionary change afoot. The automakers and their suppliers want to "touch the buyer and ripple buyer information back to corporate," continues Lipa. And eventually to the assembly line.

In short, one-on-one marketing is taking hold of the automotive industry.

Both customer relationship management (CRM) and advanced planning and scheduling (APS) make one-on-one responsiveness possible. They help companies move from a forecast-driven world to a more pull-based one. But when that happens, there are fewer speculative builds, more build- and assemble-to-order environments, and volatility goes up, warns Lipa. "Today's plants can't handle that."

More to the point, current manufacturing execution systems (MES) can't handle that. MES needs to have "bi-directional, real-time linkages" to the enterprise system, along with the CRM and APS systems. Lipa says that for the first time ever, plants and their executions systems must be a relevant part of the automakers' business strategies. In fact, corporate strategy for e-business demands it.

Ironically, those plants with complete flow lines that churn out a particular product day in and day out have, according to William Swanton, vice president of Manufacturing Strategies at AMR Research(Boston, MA), "leaned themselves out so much that they don't need MES."

But now they do. This vague thing called MES is now a critical data source. So change is afoot in MES, as well.

Standard, But Configurable

"MES describes an area of work," says John Woods, director of Manufacturing Floor Systems for General Motors (Detroit, MI), "a space generally critical to the operation of the plant." That space, consisting of an integrated collection of applications, is between controls and enterprise systems. Swanton defines MES simply as the system that knows what the order is, knows something about that order, and can electronically communicate that information to people and machines.

Whatever MES is, the OEMs don't have it as commercially available products. Whatever they have, they've developed. For instance, the basic material broadcast and sequence implemented throughout GM worldwide is a highly customized system developed by GM. Granted, development and implementation came with outside assistance from a systems integrator, such as EDS, but that assistance was performed to a specification or project definition, often on a per plant basis.

Nowadays, pieces of MES are showing up as packaged applications, though "we don't see any vendors targeting `run an automotive assembly plant' as a product," muses Woods. As a result, the OEMs (and Tier 1 suppliers for that matter) are "trying to redefine their automated systems along these commercially available modules," says Clif Triplett, GM's Global Production Process Information Officer. For example, GM is trying to "break manufacturing execution down to maybe 10 or fewer key modules with more clearly defined interfaces," says Woods, rather than keep and maintain the "hundreds and thousands of integration points" that currently exist in the assembly line systems. Applying the 80/20 Rule, retrofit and new-plant implementations will be much faster with these modules, and the automaker's customizations will be minimized.

Frankly, OEMs and suppliers are probably not looking for MES, per se. Instead, they are looking for "off-the-shelf, configurable solutions to particular problems they want to address. That may be a subset of a fully integrated MES," says Marty McGraph, vice president of Marketing for Real World Technology (Mt. Prospect, IL). Configurable is key, because the plants' "uniqueness is something they can't break out of box," adds McGraph.

On the other hand, the OEM and Tier 1 suppliers are eschewing uniqueness. By running their plants the same way, they can measure the plants against each other, apply the best practices learned in one plant across the entire enterprise, and swap out parts of the plant. Easily installed, easily configurable off-the-shelf MES packages would help here, and substantially reduce implementation time and cost.

Accessing State Information

What OEMs and suppliers are looking for is the current state of a customer order in the build process, right down to the current status of a given device in manufacturing. Ideally, MES would communicate state information about individual production equipment and the results of that equipment's execution cycle—against a multitude of subassemblies that constitute a customer order.

MES isn't that all-encompassing yet. But that time is coming because OEMs are insisting their suppliers be more closely coupled to the build schedule and production flow in the assembly line. To do this efficiently, automotive suppliers must be able to see order status, material and subassembly consumption, quality issues per part, and lots more information right from the station or line they're feeding—in real time.

To do this, the OEMs will need a more accessible information system to partner in the supply chain, though it need not necessarily be a single MES product, says GM's Triplett.

Without implementing the next generation software, the MES vendors are beginning to address this. First, TCP/IP is replacing the proprietary message transport used in most MES components today. Second, the directory service found in current MES is being replaced with a user account management facility that scales well within a growing production line, a growing plant, and across multiple plants and multiple suppliers. Such a facility also eases security, access control, and network management—all critical elements in far-flung supply chains. (Some of this is promised in the upcoming Microsoft Windows NT 2000 operating system.) Third, the MES suppliers are replacing their generally proprietary structure of presenting and accepting MES data with more open, industry-standard structures and protocols, such as those from using a web browser and Extensible Markup Language, respectively.

Take the MES state information, add a browser interface, connect using Automotive Network eXchange (ANX), and now suppliers have secure, direct access to the OEM's production line. The cost to get information to the supplier: Practically nothing. In contrast, today's approach to providing data access to the assembly line typically requires a proprietary infrastructure.

What's Happening, Where?

Considering all that has been written about MES tracking capabilities over the past 15 years, the latest trend in MES is: implementing MES tracking. Till now, automakers were more interested in equipment status and inventory control, so production tracking systems were put aside, explains Johan Ellerup, GE Fanuc's Senior Automotive Application Engineer.

Now everyone has a genuine interest in knowing what's happening on the production floor. To OEMs, data collection helps make processes repeatable and measurable. To suppliers, data collection is critical for monitoring vendor quality and component genealogy, namely liability and warranty issues. The suppliers want to be paid for the automobile content they provide, and they do not want to pay more than their fair share of product failures where more than one supplier is delivering a critical component or subassembly.

All participants in the build process now want time stamps on everything entering and leaving a production process.

Helping matters is the reduced fear that data collection might slow things down, no longer an issue given the advances in automatic identification technologies, such as bar codes and radio frequency identification. These technologies are now very much an integral, or integrateable, part of MES. Conversely, the data contained in MES is being made available across conventional electronic data interchange links, as well as increasingly across the Internet and across mobile (wireless) networks.

Sequencing Magic

According to Ellerup, one OEM estimated that if an MES could provide a 5% to 10% improvement in sequencing blocks of car assemblies for painting, the OEM would save two tanker trucks of solvent, the price of the solvent, and the associated environmental issues.

Why an MES? In automaking, the planned execution of build orders is a balance among consuming assembly plants and suppliers. Because planned execution spans both assembly plant and suppliers, setting the sequence and communicating that sequence to the world is high-level function typically relegated to enterprise resource planning systems. However, within this execution process is the need to manage that sequence—and recover that sequence as needed. That's where MES comes in; MES controls the operations that support the sequence.

Effective sequencing is at the core of how OEMs differentiate themselves, which is why they typically develop sequencing algorithms themselves. "If the MES supplier offers that, great," says GM's Woods. But what's more important is that the OEM can plug that algorithm into the MES and the MES can execute to that algorithm. "An MES that prevents an OEM from executing its proprietary algorithm would put that OEM at an extreme risk," adds Triplett.

While MES develops into something more effective for automakers, the OEMs and Tier 1 suppliers—the companies most needing such integrated systems—are winging it, doing what they can when the technology affords such capabilities. Eventually, through IT and manufacturing-specific standards, an appropriate division of accountabilities, and evolving off-the-shelf software applications, automotive MES itself will become a competitive advantage.