Objects—grouped-together packets of code—continue to improve control and human-machine interface (HMI) software for users. Using compatible objects:

• Improves software interoperability, making information sharing easier and more efficient, leading to greater user productivity;
• Allows dissemination of real-time operational information throughout the enterprise;
• Gives users or system integrators more flexibility to expand or create customized solutions, using best of breed applications without project-specific custom code. Expanded object libraries of pre-built classes and components carry into future implementation; and
• Speeds new vendor software to market because objects can be reused.

Objects also can replicate the look and feel of control systems hardware and appeal to control engineers with an affinity for icons.

While objects have been used for years, widespread use of Microsoft (Redmond, Wa.) technologies—COM, DCOM, ActiveX, VBA, and OPC (see list of terms)—have created common ground for automation and process control software vendors. Virtually all major discrete automation and process control software vendors incorporate these object technologies. Many kinds of hardware now have OPC-compliant objects inside, so they can behave as clients on a distributed network, "reporting to" an OPC server.

ActiveX-based objects can be called "plug-and-play;" the ActiveX wrapper allows the code packet to be used independently of software brands. Such a common workspace frees code writers and users from a tangle of software "drivers," or translations, from one software to another. Objects ideally provide free information flow among levels, lines, processes, or plants using different software or different versions of the same software.

Commonly licensed Microsoft technologies solve user demands for base-level compatability. Even so, at higher levels, vendor approaches become less compatible, or even incompatible.

Control software from two vendors can be compared to the twin towers of the World Trade Center in New York City. Moving between structures requires getting down to ground level or below. COM and DCOM are the sublevels, OPC is ground level, and ActiveX is the basic means of transport within and between buildings. Companies and groups of companies are developing differing strategies for building bridges (exchanging information) at higher levels; compatibility there requires cooperation among partners on each side.

Differentiating factors cited by object-technology vendors include the depth to which each uses the Microsoft-based tools, security, and strategies implemented at higher levels.

"Component architecture is delivering lower cost of ownership and the real-time transfer of data between the plant-floor and business enterprises," says John Powley, consultant engineer, Intellution Inc. (Norwood, Mass.) "Component technology lets you realize true integration similar to what computer integrated manufacturing has been promising for nearly 20 years. Intellution's FIX Dynamics is unique in that it has embedded ActiveX into its architecture," claims Mr. Powley.

In an application at the Bridgestone/Firestone Aiken, S.C., plant, engineers using Intellution's FIX Dynamics appreciate the ability to mix and match Intellution components and third-party applications. Andy Bedingfield, Bridgestone/Firestone engineer for component preparation and process systems development, appreciates "ease-of-use, speedy implementation and smooth integration, at all levels of manufacturing," with as much as a 60% decrease in integration costs, compared with custom development.

The Iconics (Foxborough, Mass.) "OPC-to-the-Core" infrastructure, developed over the past two years, provides "unparalleled reliability, ease of reuse and performance," says Russell Agrusa, Iconics president. New Genesis32 is based only on COM, ActiveX, and OPC. "We have a large library of OPC Servers that fully comply with the OPC 1.0 and soon OPC 2.0 specification." Iconics claims to be the only company that has OPC Clients and Servers (as of mid-August); "All interprocess and out-of-process communications is achieved through OPC," Mr. Agrusa says.

Wonderware (Irvine, Calif.), a long-time user of objects, now uses them as a way to expand functionality of its own software offerings. John Theron, marketing director, says Wonderware migrated from proprietary object-oriented methodology in its initial InTouch HMI program in 1989 to today's Wonderware FactorySuite 2000 products with Microsoft's latest ActiveX, COM/DCOM and DNA (Distributed interNet Application) architectures, using FactoryObjects as metaphors for the plant and its products. Vendors develop objects as ActiveX controls, adding to FactorySuite capabilities. The fuzzyTECH runtime fuzzy logic module created by Inform Software Corp. (Oak Brook, Ill.) adds fuzzy logic capabilities for PC-based control and process visualization applications (photo).

Mitch Vaughn, manager Special Projects, USDATA (Richardson, Tex.) says USDATA's Xfactory exchanges data higher in the structuring using Microsoft Windows DNA (as operating system functions), a standard set of services that address the three tiers of modern distributed applications: user interface and navigation, business processes, and storage (diagram). "Many companies in our industry are currently focused on using COM technology to create their own proprietary frameworks and infrastructures. USDATA is relying on Microsoft's DNA technologies and products for user interface and navigation and storage. We are focusing efforts on the business processes tier where the application specific knowledge is delivered."

ObjectAutomation's (OA, Santa Ana, Calif.) Rob Rennie, chief Framework Architect—responsible for OAframework design and development—says OA employs objects throughout the OAenterprise product. "Before the OAenterprise, component-extended HMI applications were simply a system of COM components running in an HMI window that hook, via property to tag connectivity, into a basic, nonreusable, linear tag database. We've turned the 'tag database' into a system of distributed objects and associated classes, allowing far tighter—most often one-to-one—integration of graphics, control, SCADA, and other objects and components."

System integrators have "unprecedented access" to object-oriented paradigms through the OA Object-Based Control initiative, benefiting from object-oriented technology (OOT) design without knowing the inner workings. Use of COM throughout will allow users to eventually choose best of breed components and classes when designing an integrated solution, as they do in the OA HMI layer now. Partners such as International Laboratory Corp. (Hiroshima, Japan) are developing objects that proxy (or mirror) existing PLC programming for the OAframework.

Object-oriented design does not guarantee a bug-free environment. "You can write bugs in any language," says Michael Hajjar, PC Soft International (Braintree, Mass.) vp, corporate accounts and business development. PC Soft's design, based on Microsoft Family Class (MFC) Libraries, "forces you to be more disciplined. And because MFC is a big body of code that is already debugged and proven, you get a higher level of functionality with a lot fewer bugs."

OPC and ActiveX isolate code between servers and clients, and between the data source and its interfaces, but (as the least common denominator for data transfer) don't deliver enough inter-application functionality, says Mr. Hajjar. Shared class libraries between products developed by the same vendor (such as PC Soft) and its partners will be the most decisive long-term factor for a high level of application integration and interplay, he says.

Intellution's FIX Dynamics' "i-core framework" features Secure Containment (patent pending), which immediately identifies any problem control or component introduced, isolates the misbehaving object, and enables the system to react and recover smoothly, explains Mr. Powley. This feature ensures high system performance and reliability—functions absolutely essential in process control applications.

Mr. Theron says Wonderware is implementing a certification process and a test tool for third-party components that run in process without performance penalties and recommend noncertified nontested components run out of process.

Mr. Rennie says that using OAenterprise, an integrator may "link" two object attributes together and be assured of connectivity, whether the OA Event Services are used or the connection is "translated" into connectivity specifications at a lower, perhaps control network layer.

"The ultimate goal of any conscientious object technology provider should be the elimination of 'glue' or integration code that must inevitably be written. While it can never be completely eradicated, it can certainly be minimized," he says, by staying within the OA architecture, above COM and OPC.

Key to creating robust and bullet-proof object code is in the component-creating tools, according to Mr. Agrusa. Iconics has recently released its ActiveX OPC ToolWorX product (see related photo) to create device drivers. The patent-pending technology allows developers to create in a week as many OPC-enabled ActiveX Controls as previously took four to six months. Iconics has sold more OPC Server and Client side toolkits than anyone else, he adds for HMI, SCADA, or control applications. Another Iconics technology provides ActiveX "object fence protection" for Iconics' client HMI, trending, and alarming applications.

National Instruments (Austin, Tex.) Jack Skruggs, the Lookout marketing manager for National Instruments, says that, "With established object-based software users can leverage large libraries of field proven object classes. One example is the pager object class in National Instruments' Lookout 3.8—it enables users to send dynamic text messages directly to pagers through a user supplied modem."

Mr. Rennie says OA has "a wire-level compatible DCOM implementation." OA distributes its COM interfaces (and helper functions) to technology partners (licensees) for plug-ins and/or custom objects.

ActiveX and OPC are the real standards because a user can immediately benefit from multivendor product integration with no additional effort, Mr. Hajjar says: "You don't have to buy everything from one vendor," he adds, taking a poke at OA's licensing program. "A software company developing applications for the Windows environment that does not use MFC and other Class Libraries will not be in business for long." PC Soft's foundation class library delivers 80% of code needed for creating an advanced highly graphical environment of logic and graphics. (See related photo.) "Only our source code is open. If a vendor doesn't share code, then cost of sharing objects is too high," Mr. Hajjar suggests.

Mr. Agrusa says many vendors are creating objects using Iconics' tools. "With the right tools, implementing objects is like jackhammer compared to a chisel, allowing access to 3 MB of source code by clicking a few buttons." In 18 months, 100 OPC tookits and 25 ActiveX toolkits were sold to the likes of ABB, Bristol Babcock, Foxboro, Honeywell, Johnson Controls, Phoenix Contact, Westinghouse, and Yokogawa.

CORBA, an object model used at some higher levels, hasn't been implemented by control software vendors. Mr. Rennie says OA selected DCOM over CORBA, in large part because "there was just one, very large, vendor of DCOM," Microsoft. Even so, OA customers who have existing CORBA systems for manufacturing execution systems (MES) or enterprise resource planning (ERP) software can use DCOM/CORBA bridge technology to integrate levels.

Marcus Schmidt, Microsoft industry marketing manager for manufacturing, says COM reaches higher levels, as well, with ERP suppliers such as Baan, Peoplesoft, and SAP using it. In addition to integration advantages, COM will maintain backward compatability as it evolves, especially important in manufacturing, Mr. Schmidt suggests. Microsoft upgrades, such as "COM+ in NT5, will make it even easier for developers to build a higher level of functionality with a lot less programming," agrees PC Soft's Mr. Hajjar, predicting wider Microsoft power and reach.

Customers know objects allow greater reuse of code, increasing functionality. Common ground creates greater connectivity, but users will have to wait and see whose model wins on the upper floors.