The use of computer-based simulations to analyze planned manufacturing operations isn't new. However, these exercises have been less than optimal, due to a critical "missing link" that has contributed to delays and higher costs in getting new production equipment up and running. Now that gap has been filled by a team of scientists at Rockwell Automation, a unit of Rockwell International Corp., with the development of Enterprise Controls software. By integrating the development of control systems for programmable logic controllers (PLC) into the design process, the software closes the loop from part design to accurate machine simulation. In essence, Enterprise Controls converts data from a part designer's CAD system into a control program that can be used to animate the "virtual machine" simulation -- and, later, to create the program that will actually control the machine on the factory floor. By incorporating PLC control into the simulation stage, manufacturers will have "a much more detailed and accurate view of a machine, thereby reducing errors and startup costs," Rockwell Automation points out. As a result, design engineers and equipment designers "will be able to validate more and more of their manufacturing processes before they are committed to developing machinery. This will allow quicker startups, more flexibility in the manufacturing process, and faster payback in introduction of new products." One reason for the faster payback is that the lengthy process of debugging control software will be drastically reduced. With Enterprise Controls, information from simulation systems about machine movements is translated not only into PLC control programs, but also diagnostics, operator interfaces, and factory information systems, Rockwell points out. The software system was created as part of a next-generation manufacturing system being jointly developed by Rockwell Automation with DaimlerChrysler AG (which will beta test the technology), Dassault Systemes SA, Deneb Robotics Inc., and Progressive Tool & Industries Co. A "proof of concept" demonstration was conducted at an automotive conference earlier this year in Detroit. The overall system -- which DaimlerChrysler has dubbed CPGA, for control program generation and analysis -- will "reduce the time it takes to program a typical work cell by thousands of hours, shave two to four months off the development time of passenger vehicles, and save upwards of $20 million per assembly plant," predicts Frank Ewasyshyn, DaimlerChrysler vice president for advanced manufacturing engineering. The approach is unique in terms of its scope, says Rich Ryan, president of Rockwell Software. "It's an end-to-end problem solution -- from product design to the production process side," he points out. One key is that it provides a "common data structure," linking various elements of a manufacturing organization -- product designers, process designers, and controls designers. Traditionally, Ryan notes, each entity has used its own software tools and created its own databases. "And there were thousands of hours of meetings -- and manual intervention -- in passing information from one part of the organization to another. All of that contributed to the overall time that it takes to design a vehicle." With the new software, the manual intervention and engineering work required to write the code that controls the sequence of machine operations will be dramatically reduced. "By taking the part design information, and using some knowledge of the way the control system works, the sequential process design is automatically linked to the design of the part," says Ryan. One significant result of having a common data structure: simulation tools will become available to part designers that will show them how efficient the production process for a particular design will be -- thus enabling manufacturers to more accurately calculate return on investment upfront. "For example," Ryan says, "what's the cost for making a body side panel that has one ridge in it, versus two for structural integrity? Now the designer can dynamically [determine] that as part of the whole design process."