The controls sector is sizzling with innovation, with flexible PLCs, multifaceted open control, and Web-based applications promising greater efficiency and ease-of-use. Dick Slansky, senior analyst at ARC Advisory Group, observes that "most OCS suppliers have gone beyond the standalone soft-logic PLC replacement business model, and offer a suite of automation applications that may include HMI, soft-motion control, soft CNC, factory database functionality, development tools for controls integration, batch management, I/O configurators, schedulers, and, more relevant today, a Web server." According to ARC, worldwide revenues for OCS providers are projected to grow from $69 million in 2001 to $200 million in 2006. (For more, click here.)

"The overall trend here is to add to the existing custom hardware a more flexible hardware and software environment, where the complexities of a particular application can be easily translated into a control solution, and change is easy to implement," says Brian MacCleery, distributed I/O product manager at National Instruments. "The key hardware component to make this a success is an industrially rugged and modular I/O platform that can easily be expanded, has a wide variety of plug-in I/O modules, rich networking capabilities, and can be located remotely throughout a manufacturing environment," states MacCleery. (For more, click here.)

Manufacturers are selecting modular and open technologies "that can be easily integrated with subsystems and components from various suppliers," notes Jerry Yen, manager, Common Controls Technologies at General Motors Powertrain Manufacturing Engineering Group and co-chair of the OMAC (Open Modular Architecture Control) Users Group. (For more, click here.)

Integration Is Key

Full integration is a key concern. "One of the most important concerns in the controls sector is how to efficiently integrate shop floor control and monitoring information with the top floor IT enterprise information systems," says Greg Woods, president and CEO of Control Technology Corp. "In a practical sense, there are two problems to overcome: How to get the data from the shop floor to the top floor and how to format the data. The obvious answer to nearly everyone in the controls industry to the transport question is to use wired or wireless Ethernet networks."

Data formatting is a murkier area. Users appear to be wrapping Ethernet around existing Fieldbus or proprietary protocols "so that they can be transported over an Ethernet hardware backbone or worse yet, some are making no changes and simply recommending the use of a serial to Ethernet hardware converter," Woods contends. These cost-cutting measures do not answer formatting concerns. "The ideal solution would be a controller that can communicate directly via XML and/or SQL," Woods believes. (For more, click here.)

Adds MacCleery: "The emerging new generation of programmable control systems lowers initial investment costs, due to its user-defined, software powered, short time to deployment nature, with many built-in tools to increase productivity. This is especially beneficial for smaller manufacturing operations that would otherwise find the costs prohibitive of contracting out the design, installation, and support of the automation system." Meanwhile, manufacturing engineers can develop and maintain automation systems in-house using graphical development environments such as NI's LabVIEW and industrially rugged modular I/O systems, including FieldPoint (pictured).

Omron combines PLC control, DeviceNet, and wireless communications. Its CPM2C-S DeviceNet slave programmable controller "provides up to 106 local, and 256 distributed I/O points, 20-kHz high-speed counter inputs, plus a real-time clock," states Joe Rubino, software product marketing manager at Omron Electronics LLC. "The local I/O control can be processed with the CPM2C-S PLC and communicated wireless on DeviceNet, through the WD30 to the main controller. This reduces the costs of more expensive devices for the I/O connections, replacement parts, associated equipment downtimes and maintenance costs," he notes. (For more, click here.)

Many products do not fully meet certain international and industry standards, Yen cautions. These lapses result in "many integration issues at the end user sites." His solution: "Companies must cooperate in industry-wide groups to agree on 'implementation' standards, i.e. how to interpret and implement standards in the same manner. Neutral validation labs need to be established to certify the integration of these products."

Yen continues: "The reliability of the communication networks and components that support critical manufacturing operations, including common protocols and wiring and interface cards, is a major concern. It is important for manufacturing systems to have self verification of system integrity capability, especially for devices and controllers. The control systems for manufacturing equipment/systems have to be easier to use and troubleshoot."

Rugged Hardware, Flexible Programming

Rugged embedded hardware and flexible programming are transforming control technology. "A new generation of industrially rugged embedded controllers designed from top to bottom for manufacturing environments and measurement and control are emerging," MacCleery tells IEN. Meanwhile, "rigid programming tools are being replaced with more flexible programming environments consisting of libraries of function blocks that can be used as-is, or modified to suit the exact needs of the application."

And controllers can perform multiple tasks, as well as prioritize critical control loops. "One controller can be used to open and close valves, run analog control loops, log data, perform real-time simulation and analysis, and communicate over serial, phone, and Ethernet," explains MacCleery. "The controller can publish its I/O data automatically to an OPC server and SCADA software package located on a host machine, or be configured for completely standalone operation."

Distributed control is making a mark, too. Copley Controls Corp's new CANopen amplifiers and linear motor products integrate to produce a distributed-control motion-control system. "Combined with other sensors and I/O products that work under the CANopen protocol, the net effect is to eliminate the traditional motion-controller card and its attendant language, replacing them with a single command program in the PC," states Jim Woodward, applications manager at Copley Controls. (For more, click here.)

Yen expects the role of the Ethernet in controls to increase, although a real-time Ethernet standard "needs to be adopted in the industry to avoid another Fieldbus war." While the OMAC concept has many adherents, the cost of validation may be a sticking point.

And the tug-of-war between PCs and PLCs seems to have ended in a tie, at least for now. "There's a place for PCs and a place for PLCS," says Bill Arnold, I/O production marketing manager at Omron. Open architecture is really taking place on the I/O level: "You can hang just about any HMI on any PLC," Arnold notes.

Woods foretells a time when the "more innovative controls manufacturers will figure out how to make their devices appear and function like an IT database," complete with "bi-directional XML and SQL support. Ideally these devices will be accessible over the Internet as well."

Stable components will remain essential in such an environment. "It is vital that manufacturers install a cabling infrastructure that will withstand the demands of industrial environments to avoid network interruptions," emphasizes Frank Koditek, industrial marketing manager at Belden Electronics Div. (For more, click here.)

Internet Influences

Controls are also moving to the Internet. Explains Scott A. Kortier, GP/GLC product manager at Xycom Automation Inc: "A web-based HMI/controller can allow an OEM to go above and beyond phone support by viewing the status of a machine from many miles away (or even in another country) -- Xycom Automation's GP-Web product allows someone to view and optionally interact with remote machinery, over the Internet or via an Intranet, using only a standard Web browser." (For more, click here.)

A shortage of technical experts will accelerate use of the Web, according to Woods: "Any tools that enable them to manage several sites from the home office -- or from home, for that matter -- will be adopted more and more. Technology is enabling people to do more and more from a remote location -- including start-up, troubleshooting, and upgrades." Additionally, standards including SOAP, XML, and SQL allow engineers to connect devices to the enterprise "with minimal input from IT," says Woods. He also believes that "adherence to established security standards such as MD5 digest authentication (as well as certificate-based HTTPS) can ensure that data stays safe."

While the popularity of lean manufacturing pulls many manufacturers toward advanced control technologies, users should choose carefully, MacCleery tells IEN. "My advice would be to evaluate any control and instrumentation system in terms of its reliability and your productivity in using it." He recommends using a checklist of questions: "Does it offer the productivity features that will allow you to get up and running quickly and adapt to the changing demands of the market? Is it designed for harsh industrial environments? Does it offer a mean time before failure (MTBF) rating of 25 years or more?"

How easily can new controls technology be tied into existing components? "This depends on two factors," according to Woods -- "what standards and conduits are supported by the new and the old systems and how committed the enterprise is to connecting the two."

According to MacCleery, the mature and young technologies can be linked up with relative ease. "The new generation of intelligent control systems, such as NI FieldPoint, integrate well with legacy/traditional components and add advanced analog control, measurement, and signal processing capabilities to the systems," he states. "Technology such as OPC connects devices to the same host computer or SCADA package, even across different fieldbuses.

Yen contends that the pain differs by industry. "In heavy manufacturing industries, where life cycles are long (10-20+ years), the integration of advanced control technology with legacy systems is a major issue because of the incompatibility of the technologies. For shorter life cycle manufacturing (1-5 years), the integration of advanced and legacy technologies is an added cost."