Integración De Modelos De Manufactura

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Applying Computer Technology to Manufacturing
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By Keith Unger

Move over, CIM. Today it’s ERP, MRP, MES, REPAC, and SCOR.

here is a new landscape in manufacturing applications. The computer-integrated manufacturing (CIM) pyramid of the 1980s has crumbled to make way for a variety of better models for manufacturing information technology in the 2000s. TheSupply Chain Operations Reference (SCOR) model; the Manufacturing Execution Systems Association (MESA) model; and AMR Research’s Ready, Execute, Process, Analyze, and Coordinate (REPAC) model all define manufacturing applications from a functional point of view. Meanwhile, you can define manufacturing applications from the point of view of vertical markets, specific implementation models, and abroad range of functional categories. In addition, manufacturing applications have evolved from custom solutions to tool kits to commercial, off-the-shelf packages. And that is in addition to the functions that manufacturing applications provide for supply-chain coordination, enterprise resource planning (ERP) connectivity, planning, scheduling, inventory management, and shop floor data collection.There have been many acronyms and models in the past two decades that describe the topic of manufacturing application soft-

ware. However, regardless of naming and modeling, manufacturing’s fundamental needs have not changed significantly. What has changed is the availability of commercial software, experience in applying software applications to manufacturing, and the emergence of standards forapplying software and computer technology to manufacturing. Today, many well-developed tools are available that can be successfully applied to meet the functional needs of manufacturing processes. Experience gained applying software and computers to manufacturing has been well documented, and international standards communicate generally accepted best practices in manufacturing systemsintegration. Manufacturers today can take advantage of experience gained from early adopters’ efforts and apply current technology with a high degree of confidence that the application will successfully meet requirements. In the 1980s, industry movers and shakers introduced the concept of CIM, and the CIM manufacturing software pyramid model was developed. The CIM pyramid model focused on the hierarchy ofthe manufacturing enterprise. It divided the manufacturing domain into five

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levels of computing functionality. During this time frame, technology tools fit one or more CIM levels. Programmable logic controllers and loop controllers became the dominant technologies at the control level, and a whole market of supervisorycontrol and data acquisition suppliers emerged to fill the needs of level two supervisory systems. Corporate financial systems and functionality needed to support overall operations resided at the top of the pyramid. At the divisional level of the pyramid, the focus was on material requirements planning to meet customer orders. This planning process estimated capacity and material requirements based ona combination of forecast orders and actual orders for a specified time.

MES Systems Emerge
In the first half of the 1990s, new pressures and ideas began to change the shape of the CIM pyramid. Manufacturing was moving from an internal focus to a customer focus. Global pressure to compete for customer loyalty with high-quality products delivered when and where customers wanted the productsrequired manufacturers to be more responsive. As a result of these pressures and ideas, the CIM pyramid collapsed and flattened out, and the new MES model evolved. In 1992, Cambridge, Mass.–based AMR Research introduced the three-layer MES model. This model reduced the manufacturing system problem set to three functional areas of planning, execution, and control. The model helped the industry by...