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Data definition The same item of engineering data may be defined differently in different parts of the organization, often with the result that the definitions conflict. This results in confusion and waste when data is transferred from one part of the organization to another. Duplicate and redundant data A lot of engineering data will be held in duplicate. Many users keep several copies of data and try to stop other people accessing them. As a result, different groups of users often have different copies of what should be the same data. The design engineer will have a copy of some of the information that is used in production planning. Copies of some of the information used to generate NC programs will be kept by both design engineers and manufacturing engineers. Maintenance engineers may want to keep 'their' drawings close to hand so that they can respond quickly to urgent customer calls. Most of this information will also be stored elsewhere in the company. Vocabulary People in different parts of the company use different words to describe the same thing. Sometimes they use the same word to describe different things. Data ownership The real ownership of engineering data is often unclear. It is not always clear which information belongs to which part of a company's organization. Even within a particular part of the organization, such as the Engineering Department, it is not clear who are really the owners of information. Designers, analysts, drafters, supervisors and managers will all have their own ideas as to ownership of information. They will probably be willing to defend what they see as their property if anyone suggests that ownership of the information should actually be assigned to somebody else. Although they may want to own the data they may be less willing to accept the responsibilities of maintaining it properly, and making it available in suitable form when it is needed by others. Similar ownership issues arise when data is shared with suppliers and customers. Volume of data The sheer volume of engineering data makes it difficult to manage. Estimates for medium-to-large companies foresee data volumes exceeding 1 million Gigabytes (GB). There are currently no devices available to effectively manage such a volume of data with the characteristics described above. Since the creation of files ranging from 50 KB up to 1 MB, or even 100 MB, only requires a few minutes, it does not take long, even in small companies with only a few users of computer-based engineering data, for manual data management techniques to break down. In larger companies, with several hundred engineers, many GB of data may be created and accessed each week, and the problem is getting worse and worse. The ability of users to create data has overtaken the capability of manual data management systems. Security In view of its volume and wide distribution it is not easy to keep engineering data secure. It would be easier if security rights were always the same, but they often change during a project life cycle. In addition, users may have different rights on different projects. For example, some designers will not have the right to see some information, and some maintenance staff will have limited access rights to particular parts. Archiving Engineering data must be kept for a long time. Companies have to keep data that is on both traditional and electronic media for similar periods and similar purposes. In the same way that some traditional media deteriorate, some electronic media are also not suitable for long-term storage. Access to original electronic data will be complicated by the rapid obsolescence of computers and the introduction of radically different systems. For example, new generation CAD systems will pose a problem. They will have difficulty in using old 2D and 3D data produced for old products by old systems. Just as geometric modeling programs used in the mid-1960s have been superseded, today's programs will, in turn, be superseded. Companies will have to manage old data (for old products), enriched data on old products, and data in new formats. Corporate asset A company's engineering data represents its collective know-how. It should be used as profitably as possible. Increasing computerization of engineering activities and the resulting growth in the volume and availability of digital engineering data will result in engineering information becoming an important company asset. Life cycle data Engineering data is used throughout the product life cycle. In some cases, for products such as aircraft, the overall product life cycle may be thirty or forty years. During this time, there will be a vast volume of data generated first to design and manufacture the product, and then to support its use. Islands of Data The majority of the application programs used in engineering activities are file-based. They store data directly in files under the control of the computer's operating system. Another program on a different computer can not easily access the data in these files. This is partly due to the operating system and the communications network, and results from the difficulty of transferring data from a file under one operating system on one computer, to a program on another computer running under another operating system. It is also because information about an object such as a part or product is rarely independent of the program that created it. The knowledge about the structure and meaning of the data in the file is often only available in the application program that wrote the file, and not available to the other program. As a result, even if the latter program were able to access the data physically, it would not be able to understand it. The data in a file often remains understandable only to the program that wrote it. Sets of files tend to 'belong' to the programs that wrote them. Each program tends to become an Island of Automation. For each Island of Automation, a corresponding Island of Data is built up. In medium-sized manufacturing companies it is not uncommon to find twenty or more Islands of Data. |