INTERNATIONAL CONFERENCE ON ENGINEERING ICED 01 GLASGOW, AUGUST 21-23, 2001 REDUCING DEVELOPMENT CYCLE BY DATA MANAGEMENT WITHIN THE OFFICE Mario Storga, Davor Pavlic and Dorian Marjanovic Keywords: Product data management, design information management, information representation, web-based systems. 1 Introduction Product development is exposed to increasing demands with respect to quality and costs [1]. Striving to improve and optimise the production process, companies have been increasingly computerizing certain areas of production process. Particularly in the product development process, introduction of the CAD technology has increased efficiency. In the same time, product development process within design office has inherited the traditional methods of product data management. Those traditional methods cause many problems for the companies: effort and money is spent unproductively for data recapturing; development time is extended needlessly; data correctness can not be guaranteed due to the redundant data storage and multiple data conversions between different systems. Such problems have a strong negative effect on company's competitiveness, market share and revenues. Driven by such issues, the need for a software design tools to support representation and engineering information management becomes more critical. This paper is concerned with data management system for design office of small to medium size enterprise with standardized single unit production line. Although presented research is focused on the particular company, the identification of data management problems within design office and implementation methodology are guide general. The support offered to design office from the PDM technology viewpoint is discussed. An efficient usage of PDM technology demands knowledge from a number of disciplines such as management, product development, database systems, and information technology. The aim of this research performed in cooperation with the electrical power transformer factory is to develop a framework to integrate those aspects. Product data can no longer be locked into one application or another, but must be reusable down stream, as well as up stream, and by many applications as possible [2]. Reuse introduces a different perspective on the ownership of product data. Product data may not be treated as the responsibility of any particular department within the company. Instead, all product data must be treated as a corporate asset, where different departments should have different view ports on data, and different privileges for its use. The need to compress leadtime requires the introduction of concurrent engineering techniques. All the activities need to use and share the different subsets of the overall product data. This in turn brings the need for an effective Product Data Management system that controls the creation, reuse and retrieval of product data. Such a system can serve as the "backbone" for managing the product lifecycle as shown on Figure 1. PDM manages product data through the enterprise, ensuring
that the right information is available for the right person at the right time and in the right form [3]. PROJECT MANAGEMENT PROCESS MANAGEMENT WORKFLOW WORKFLOW ERP MRO management PRODUCT LIFE CYCLE ACQUISITION / ENGINEERING MANUFACTURE EXPLOITATION process CRM Specs CAE CAD CAPP MES TechDoc product PRODUCT DATA MANAGEMENT Figure 1. PDM the backbone for managing the product lifecycle [2] The goal of the project is to reduce the design development time. After preliminary problem analysis the following stages of the project were determined: Data collection/analysis about existing design process, methods and tools; Problem identifications and solution proposal; Solution implementation; Validation. The data about existing design process, design methods and tools used within design office have been collected within following methods: Task time analysis in hours per day for all employees in the design office; Unstructured interviews with designers guided with a questionnaire proposed after the first series of interviews. The structure of this paper is as follows; in chapter 2 requirements on PDM systems are defined and key functions are described; in chapter 3 the methodology of the PDM systems introduction to the product development process is discussed; in chapter 4, test example of the developed PDM system in design office is introduced. Finally, in chapter 5, the conclusions are drawn. 2 Basic requirements and key functions of a PDM system Today, there is no generally accepted definition of what a PDM system is, but is possible to define what a PDM system should do. In order to be able to define expectations of the PDM system, the interviews were done with members of a design department office. According to founded problems and expectations, which had to be solved during the introduction of PDM system, and using the literature [4], [5], [6], the basic requirements of a PDM system were determined:
Secure storage of documents and product information in a central store with controlled access and without data redundancy The first motivation for considering PDM comes from designers frustrated from not being able to find the document they are looking for. The people may only knew that the needed documents exist in a hard copy or e-document, but the time needed to get it is not acceptable. Management of the previews designs The designers spend more time modifying existing designs for new projects, because design tasks belong in high percentages to the adaptive and variant design tasks. The traditional design document system was inappropriate to CAD tools leading. Management of alternative variants of design object Many design objects (products and documents) have alternative variants. For example, the main assemblies of power transformer can be made in several standard variants, or a technical documentation for a particular product can be available in different languages. Management of the inspection and approval procedures Design tasks and design objects should be checked and approved with prescribed procedures enabling results independent on a his or her experience. Management of the recursive division of design objects into smaller components Almost all design objects of electric power transformer have a hierarchical breakdown structure, which divides the design object into assemblies, which are further divided into subassemblies, components, etc. Management of a multiple structural views of a design object. A PDM system should make it possible to have different views of a design object. For example, document structure and content level of detail, varies with the purpose of the document (contract, manufacturing, test, maintains). Software tool integration From the designers' viewpoint, the usability of a PDM system depends very much on how well the system is integrated with other tools needed in daily work (of special importance is the exchange of product information with the CAD system). Component and supplier management The management of standard components from external suppliers is significantly time consuming, because inconsistency in design data between different producers. Based on this requirements the following key functions of PDM system were determined: product data modelling, design process information management and design workflow management, as shown on Figure 2. Product Data Modelling Product data model includes data definition and classification, describing products properties and related document data, as well as relationships between them. To ensure efficient storage and data retrieval, a methodology for data classification has been established according to the specific needs of the company. One of the fundamental properties of any product is a breakdown structure, that describes how the product is divided into assemblies, which are in turn divided into sub assemblies, etc. Documents relating to assemblies and subassemblies are similarly structured, maintaining relations between documents and the products structure elements. Generally, companies are increasingly interested in configurable products, which
may be adapted individually for customer requirements. In case, all standard variants of the electric power transformer have been described with generic product structure, which is the basis for modelling the electric power transformers data. WORKFLOW MANAGEMENT PROJECT PLANNING & CONTROL USER/WORKFLOW MANAGEMENT WHO, WHERE AND WHEN PROCESS INFORM. MANAGEMENT TASK DECOMPOSITION PRODUCT DATA MODELLING FLOW PLANNING CREATION/REUSE OF PRODUCT DATA PRODUCT STRUCTURE DEFINITION STATUS DOCUMENT/ RELATIONS KNOWLEDGE MANAGEMENT WHAT, HOW CONFIGURING THE PRODUCT STRUCTURE CREATION RE-USE CAE, CAD, CAM, TECHNICAL PUBLISHING Design process information management Figure 2. The key functions of PDM system Design process information management includes activities that create or use product data. Among the required functionality of data processing support are: easy data capture, indexing and storage; fast data browsing and retrieval; multi-view data representation; data transformation between models/views and consistency management. The key property is that user needs to be able to 'get at' assemblies and subassemblies data by a variety of routes. User could move up and down through the product tree structure in different ways; pick the path through a product structure; simply call-up data user want by searching for it by name or number, or search for groups of data by specifying an attribute or combination of attributes. Every modification must be separate captured, because different versions can represent the evolution of a product through development stages. Design workflow management Design workflow management covers user rights, design task assignments, project planning and control. The term 'design workflow' refers to the flow of work through design activities in which design data need to be created, modified, viewed, checked and approved by many different people, perhaps several times over. Design workflow is not a linear process; it is a complex process in which some activities run in series, and some run in parallel. The traditional design workflow is inefficient. Unnecessary steps, time-consuming changes make it expensive, slow, spending more than expected. It suffers from poor communications and a lack of management understanding. Therefore, it is very important for project leaders to control the progress of the project, influencing on the product development time and expenses.
3 Methodology of the developed PDM system introduction Considering the key functions of Product Data Management system from the theoretical viewpoint, the next step is the practical introduction of the system into the design office. Introduction methodology is a separate problem and will be discussed in this chapter. Successful introduction of a Product Data Management system can be a time consuming and complex process, but it is well worth the extra effort required to do it right the first time [7]. They are many issues to consider in the process of evaluating and introduction a PDM system. Each step in this process is vital to overall process success. The outline of proposed methodology is given in the following five steps: 1. Identifying specific company's needs Involves identification of specific needs and requirements from both a management and end-user perspective. A CAD operator needs a design-oriented approach to locate files and revisions while an engineering manager would be more concerned with procedures to shorter design cycle and increase the overall productivity of the department. Ad hoc solutions for data archiving are the main cause of problems in exploitation. 2. Analysing company's existing information flow The data about the workflow and processes in the design office, gathered through the series of unstructured interviews has been used as baseline for information flow analyses. Overall workflow is analysed with detailed look at: data flow, the data format (hard copy, digital notes...); the processes over the data; the time periods for each process and a time it takes to transfer data between processes. After this analyse, bottlenecks were identified. A bottleneck is anything that causes delays or creates extra work such a paper based transfer of information, duplicate entry of data, inefficient work methods or unnecessary procedures. 3. Designing the system's architecture Includes the database structure designing, the security scheme, the user interfaces and users' communication protocols, data presentation forms and system developing tools. The storage and memory requirements need to be determined. The number of concurrent users and corresponding network bandwidth requirements need to be determined to insure adequate performance. Additional work may be needed if the system needs to be integrated with other applications. 4. Planning the implementation procedure and implementation The key to smooth implementation is planning. The more time spent on planning, the less time will be required for the implementation. There are many decisions and questions. It is necessary to know what resources (people and time) are required, what is the implementation schedule and which documents should be considered. Designers should receive a proper training before the implementation. Administrative issues of the new system should be prescribed and familiar to each member of the design team; special care should be taken for backups and recovery procedures. 5. Maintaining the system Once the system is functional and users are satisfied, maintain become crucial. The system will meet expectations of designers only by delivering constant functionality. Therefore, maintains of such systems requires the new kind of specialist for the design office capable to solve periodical updates, solving unexpected problems and implementation of the additional users requirement, problems from the computational viewpoint and from designers viewpoint.
4 Project implementation As mentioned before, accordingly to the proposed methodology, the prototype of the PDM system has been introduced into design office of electric power transformers factory. The production process of the electric power transformer could be described as a low volume production of valuable products composed of in function highly standardised main assemblies. The range of products has been standardised by variations in structure form and performance. The most of the hierarchical structure of the electric power transformer is well known. That enables the concept of "design templates" which may be used as a support framework in the design process for appropriate new designs or redesign of the existing solutions. Design template, represents the generic product data structure, and includes: a hierarchical relations between assemblies; material information, component identification, quantities, norms, instruction documents for designing procedures and possible variants of standardized assemblies. All the activities along the design workflow create and/or use product data. The workflow exists to provide the product data necessary to produce and the support the product. Without product data there would be no need for the design workflow. Product data and design workflow are very closely linked. Based on experience from the existing design process, design data flow has been coordinated. Such coordinated data flow manages: project identification; tasks schedule planning for each project phase; current status of the pending projects; information about the previous projects; key parameters for catalogue, storing, searching and retrieving of design solutions; users' identification and status. Design activity procedures for each user's group are also included and described in [8]. Digital model of design templates and design workflow are mapped within relational database system [8]. Database structure creates an information infrastructure for virtual design environment, which is used as a core for the product data and document exchange between engineers in design development cycle [Figure 3]. PREVIOUS S AND HISTORIES PRODUCT STRUCTUR MODELS EXPERIENCE, RECORDS, CORPORATE FILES AND KNOWLEDGE PRODUCT DOCUMENTS PRODUCTS AND PROCESS DATA WORKFLOW TEMPLATES USERS AND PROJECTS DATA ENGINEERING DATABASE @ WEB TECHNOLOGY @ DEVELOPMENT CYCLE Figure 3. Implementation architecture of PDM system
Mechanisms included into the database system insure data consistency and support the activities of design information management through security storing, searching and retrieving data. Project implementation includes a realization of adaptive user interfaces that allow distributed users to fill, edit and browse engineering database [9]. User interfaces were developed using the 'Web' technology. The new dynamic features add a wealth of power and interactivity to the World Wide Web applications through dynamic data manipulation. Through the dynamic web pages the members of the design team can follow the product structure to start their own work and than to collaborate with each other on project. E- documents of the product are being exchanged using 'Web' technology [Figure 4]. Those documents include product specification, design notes, component variants specifications and on-line created Bill of Materials. Communication between the users is realised through the automatic email protocol, through which the user gets all the information necessary for his design duties. Figure 4. Example of users form with integrated e-document 5 Conclusion Generally the validation of research projects is a very subtle area. With a given goal the validation is quite clear because the measure of success is the requested reduction of design development cycle time. Described system is one part of solution implemented in real situation [10] that has demonstrate significant possibilities of reducing design time cycle by the introduction of the developed PDM system in design office. An improved collaboration and management within a product development team is a key factor to an efficient product development process. The proposed system supports the product development process on two levels: engineering data management and design data flow coordination. Data modelling is a key issue in order to achieve an effective structure that will support the product data and document management. By coordination of the engineering workflow, bottlenecks are
reduced, and better control of the projects is established. As a final result of proposed methodology design productivity was improved, data integrity was protected and design time was reduced. References [1] Andreasen, M.M., Hein, L.: "Integrated Product Development"; IFS Ltd; Springer- Verlag; Berlin NewYork London Paris Tokyo; 1985. [2] Timmerman, H.: "Do your homework, save time and money"; CD with selection of 25 Conference Papers presented at "e-business for Industry", London, 2000. [3] Schnurer, R.: "The Application of Product Data Modelling Techniques to Product Support"; CD with selection of 25 Conference Papers presented at "APLS/CALS Europe", London, 1999. [4] Peltonen, H.: "Concepts and a Implementation for Product Data Management"; Doctorate Thesis, Helsinki University of Technology, Department of Computer Science and Engineering, Finland, 2000. [5] van den Hamer, P., Lepoeter, K.: "The Philips 5-dimensional framework for modelling design data and design process"; Proceeding of the 2nd WDK Workshop on Product Structuring; pp 83-108; Delft University of Technology; The Netherlands; 1996. [6] Piskoz, P, Malmqvist, J.: "Possibilities and Limitations when Introducing PDM Systems to Support the Product Development Process"; Proceedings NordDesign '96; pp 165-175, Espoo, Finland; 1996. [7] Fries, B.: "Successful Implementation of Product Data Management Systems"; Premier Design Systems, Inc.; http://www.pdmic.com/articles/artpdmim.html; 1995 [8] Pavlic, D., Marjanovic, D., Storga, M.: "The implementation of web-based technologies in engineering data management"; Proceedings of the 6th International Design Conference 2000"; CTT, FSB, WDK; ed. Marjanovic, D.; Dubrovnik; Croatia; 2000. [9] Storga, M., Pavkovic, N., Marjanovic, D.: "Computer Aided Product Structure Design"; Proceedings of the 6th International Design Conference 2000"; CTT, FSB, WDK; ed. Marjanovic, D.; Dubrovnik; Croatia; 2000. [10] Marjanovic Dorian, Bojcetic Nenad, Dekovic Damir, Pavkovic Neven, Pavlic Davor, Storga Mario, Zezelj Dragan: "Design Department Data Flow Integration"; Proceedings 3rd International Workshop IPD 2000; Magdeburg, Germany; University of Magdeburg, 2000. Mario Storga, B.Sc. University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture, Design Department, Ivana Lucica 5, 10000 Zagreb, CROATIA, Tel: + 385 1 6168 117, Fax: + 385 1 6156 940, e-mail: mario.storga@fsb.hr, URL: www.cadlab.fsb.hr