Proceedings from the 2nd seminar on Development of Modular Products : December 13-14, 2004, Campus Framtidsdalen, Dalarna University, Sweden

Companies are focusing on efforts increasing the overall efficiency at the same time as the ability to meet customer needs becomes even more important. There is a need to improve the organisation and the product design at the same time through the visualisation of how a product family design should be performed in order to adapt to customers, company internal issues, and long-term strategy. Therefore, there is a need for qualified personnel in today’s companies with the knowledge of product development and modularity. The graduate course Development of Modular Products at Högskolan Dalarna has the objective to provide such knowledge. As a part of the course, each student will individually perform extensive research within a chosen area with respect to Product Development and Modularity. This proceeding is the result of the students own work and was presented during a two day seminar at Dalarna University. The contents of the papers cover many areas, from the identification of customer needs to cost effective manufacturing, and benefits of modularisation. The reader of this proceeding will not only benefit from many areas within Product Development and Modularity but also from the colour of many cultures. In this proceeding, students from nine countries are represented (Bangladesh, China, Costa Rica, Germany, Holland, India, Luxembourg Nigeria, and Sweden). Enjoy the reading.

Studies of Design and Assembly Defects on Integrated and Modular Architectures

It is known that despite companies’ efforts to improve the quality of their products, design and assembly defects results in large repair costs both in terms of repair and providing feedback to the origin of the defect. The purpose of this paper is to study these types of defects and the defect rates in design and assembly. The paper presents a web based questionnaire answered by 29 companies. The result shows that the defect rate (defects per product) spanned from 0.01 to 10. Also, design and assembly defects covered 46%, 23% respectively, of all occurred defects. A case study is also presented, performed at a company who recently implemented a modular architecture. In this company, defects from 5 700 integrated product architectures are compared with defects from 431 modular architectures. The average defect rate increased by 21.5% – from 0.65 to 0.79 – when a more modular architecture has been implemented. Furthermore, the study showed that the assembly defects have decreased while the design defects increased. The results presented in this paper will also support the development of the MPV (Module Property Verification) method which is briefly described.

Module property verification : A method to plan and perform quality verifications in modular architectures

Modular product architectures have generated numerous benefits for companies in terms of cost, lead-time and quality. The defined interfaces and the module’s properties decrease the effort to develop new product variants, and provide an opportunity to perform parallel tasks in design, manufacturing and assembly. The background of this thesis is that companies perform verifications (tests, inspections and controls) of products late, when most of the parts have been assembled. This extends the lead-time to delivery and ruins benefits from a modular product architecture; specifically when the verifications are extensive and the frequency of detected defects is high. Due to the number of product variants obtained from the modular product architecture, verifications must handle a wide range of equipment, instructions and goal values to ensure that high quality products can be delivered. As a result, the total benefits from a modular product architecture are difficult to achieve. This thesis describes a method for planning and performing verifications within a modular product architecture. The method supports companies by utilizing the defined modules for verifications already at module level, so called MPV (Module Property Verification). With MPV, defects are detected at an earlier point, compared to verification of a complete product, and the number of verifications is decreased. The MPV method is built up of three phases. In Phase A, candidate modules are evaluated on the basis of costs and lead-time of the verifications and the repair of defects. An MPV-index is obtained which quantifies the module and indicates if the module should be verified at product level or by MPV. In Phase B, the interface interaction between the modules is evaluated, as well as the distribution of properties among the modules. The purpose is to evaluate the extent to which supplementary verifications at product level is needed. Phase C supports a selection of the final verification strategy. The cost and lead-time for the supplementary verifications are considered together with the results from Phase A and B. The MPV method is based on a set of qualitative and quantitative measures and tools which provide an overview and support the achievement of cost and time efficient company specific verifications. A practical application in industry shows how the MPV method can be used, and the subsequent benefits

Modular Product Verifications Based on Design for Assembly

The desire to conquer markets through advanced product design and trendy business strategies are still predominant approaches in industry today. In fact, product development has acquired an ever more central role in the strategic planning of companies, and it has extended its influence to R&D funding levels as well. It is not surprising that many national R&D project frameworks within the EU today are dominated by product development topics, leaving production engineering, robotics, and systems on the sidelines. The reasons may be many but, unfortunately, the link between product development and the production processes they cater for are seldom treated in depth. The issue dealt with in this article relates to how product development is applied in order to attain the required production quality levels a company may desire, as well as how one may counter assembly defects and deviations through quantifiable design approaches. It is recognized that product verifications (tests, inspections, etc.) are necessary, but the application of these tactics often result in lead-time extensions and increased costs. Modular architectures improve this by simplifying the verification of the assembled product at module level. Furthermore, since Design for Assembly (DFA) has shown the possibility to identify defective assemblies, it may be possible to detect potential assembly defects already in the product and module design phase. The intention of this paper is to discuss and describe the link between verifications of modular architectures, defects and design for assembly. The paper is based on literature and case studies; tables and diagrams are included with the intention of increasing understanding of the relation between poor designs, defects and product verifications.

Urininkontinens bland kvinnor : ett dolt hälsoproblem

Syftet med denna studie var att undersöka förekomst och svårighetsgrad av urininkontinens hos kvinnor och hur det påverkade deras dagliga liv. Syftet var vidare att studera om kvinnorna sökt hjälp för sin urininkontinens och om de var nöjda med den hjälp de erbjudits. Studien utgjordes av en tvärsnittsstudie med kvantitativ ansats. Populationen i studien omfattade alla de kvinnor över 18 år som under en dag besökte en framlottad vårdcentral i Dalarna. Totalt delades 416 enkäter ut, varav 397 besvarades och 368 inkluderades i studien. Ett validerat mätinstrument ICIQ-UI SF (The International Consultation on Incontinence Modular Questionnaire-Urine Incontinence Short Form) på svenska användes och två tilläggsfrågor konstruerades. Resultatet visar att 54% av kvinnorna besvärades av urininkontinens där ansträngningsinkontinens var den vanligaste typen. Kvinnorna hade urinläckage av mindre omfattning, liten mängd, och påverkan på dagliga livet var låg, dock var de kvinnor med blandinkontinens mera påverkade. En stor andel sökte inte hjälp för sin urininkontinens då de ansåg att besvären inte var så stora. De få kvinnor som sökt hjälp var nöjda med den hjälp de fått. Svårighetsgraden av urininkontinens enligt ICIQ-UI SF visade att övervägande delen av kvinnorna hade obetydliga till måttliga besvär. Resultatet tyder på att urininkontinens är ett dolt hälsoproblem.

Conceptual Product Development in Small Corporations

The main objective of the thesis “Conceptual Product Development in Small Corporations” is by the use of a case study test the MFD™-method (Erixon G. , 1998) combined with PMM in a product development project. (Henceforth called MFD™/PMM-method). The MFD™/PMM-method used for documenting and controlling a product development project has since it was introduced been used in several industries and projects. The method has been proved to be a good way of working with the early stages of product development, however, there are almost only projects carried out on large industries which means that there are very few references to how the MFD™/PMM-method works in a small corporation. Therefore, was the case study in the thesis “Conceptual Product Development in Small Corporations” carried out in a small corporation to find out whether the MFD™/PMM-method also can be applied and used in such a corporation.The PMM was proposed in a paper presented at Delft University of Technology in Holland 1998 by the author and Gunnar Erixon. (See appended paper C: The chart of modular function deployment.) The title “The chart of modular function deployment” was later renamed as PMM, Product Management Map. (Sweden PreCAD AB, 2000). The PMM consists of a QFD-matrix linked to MIM (Module Indication Matrix) via a coupling matrix which makes it possible to make an unbroken chain from the customer domain to the designed product/modules. The PMM makes it easy to correct omissions made in creating new products and modules.In the thesis “Conceptual Product Development in Small Corporations” the universal MFD™/PMM-method has been adapted by the author to three models of product development; original-, evolutionary- and incremental development.The evolutionary adapted MFD™/PMM-method was tested as a case study at Atlings AB in the community Ockelbo. Atlings AB is a small corporation with a total number of 50 employees and an annual turnover of 9 million €. The product studied at the corporation was a steady rest for supporting long shafts in turning. The project team consisted of management director, a sales promoter, a production engineer, a design engineer and a workshop technician, the author as team leader and a colleague from Dalarna University as discussion partner. The project team has had six meetings.The project team managed to use MFD™ and to make a complete PMM of the studied product. There were no real problems occurring in the project work, on the contrary the team members worked very well in the group, having ideas how to improve the product. Instead, the challenge for a small company is how to work with the MFD™/PMM-method in the long run! If the MFD™/PMM-method is to be a useful tool for the company it needs to be used continuously and that requires financial and personnel resources. One way for the company to overcome the probable lack of recourses regarding capital and personnel is to establish a good cooperation with a regional university or a development centre.

Product verification and defect repair - status and considerations

Product verifications have become a cost-intensive and time-consuming aspect of modern electronics production, but with the onset of an ever-increasing miniaturisation, these aspects will become even more cumbersome. One may also go as far as to point out that certain precision assembly, such as within the biomedical sector, is legally bound to have 0 defects within production. Since miniaturisation and precision assembly will soon become a part of almost any product, the verifications phases of assembly need to be optimised in both functionality and cost. Another aspect relates to the stability and robustness of processes, a pre-requisite for flexibility. Furthermore, as the re-engineering cycle becomes ever more important, all information gathered within the ongoing process becomes vital. In view of these points, product, or process verification may be assumed to be an important and integral part of precision assembly. In this paper, product verification is defined as the process of determining whether or not the products, at a given phase in the life-cycle, fulfil the established specifications. Since the product is given its final form and function in the assembly, the product verification normally takes place somewhere in the assembly line which is the focus for this paper.

Beneftis of modularity and module level tests

Many companies implement a modular architecture to support the need to create more variants with less effort. Although the modular architecture has many benefits, the tests to detect any defects become a major challenge. However, a modular architecture with defined functional elements seems beneficial to test at module level, so called MPV (Module Property Verification). This paper presents studies from 29 companies with the purpose of showing trends in the occurrence of defects and how these can support the MPV.