Architecting the CVT final line. (WIP).

When the Final assembly line is Finally up and running at the ZF Batavia plant in Batavia, Ohio--the plant that's a joint operation oF ZF Group and the Ford Motor Co.--it will be producing continuously variable transmissions [CVTs] at a rate of better than one per minute. The assembly line, which was built by ICA Cinetic Automation Corp. (Farmington Hills, MI), consists of 44 stations: 29 manual and 15 automatic. The assemblies travel through the line on pallets that are Fitted with radio Frequency identification (RFID) tags, which both track progress and provide intimation to the assembly stations.

One of the most important aspects of this assembly line is its control architecture. ICA worked with ZF, Ford, and Siemens Energy & Automation [Alpharetta, GA] in developing a PC-deploying approach that's based on what's called "Totally Integrated Automation," a means through which various hardware and software elements based on industrial standards can be efficiently integrated. While lines like this have historically been built with a programmable controller (PLC] architecture, this was determined to be better.

Each workstation features an industrially hardened touch-panel PC equipped with the Siemens SIMATIC WinAC controller. This controller contains all of the Functionality that one might expect from a PLC, but unlike a PLC-based approach, only a fraction of the floor space is required. Each of the PCs is connected peer-to-peer; each PC has a standard Profibus interface to connect all of the various devices in the system. WinAC is based on Windows NT, but uses the same programming tools as are used For the SIMATIC PLCs that Siemens produces. Although there is some concern in systems of this type that there could be a Windows crash, there is a real-time extension component that operates apart From the NT kernel, so there is a deterministic operation. Or, to put it another way, if the ZF Batavia line had a Windows NT hang-up, the system would remain up and running to perform diagnostics online or, if necessary, after an orderly shutdown. For more about Siemens controls, write in 133 on the RSC.