Product relationships management enabler for concurrent engineering and product lifecycle management

The current competitive industrial context requires more flexible, intelligent and compact product lifecycles, especially in the product development process where several lifecycle issues have to be considered, so as to deliver lifecycle oriented products. This paper describes the application of a novel product relationships management approach, in the context of product lifecycle management (PLM), enabling concurrent product design and assembly sequence planning. Previous work has provided a foundation through a theoretical framework, enhanced by the paradigm of product relational design and management. This statement therefore highlights the concurrent and proactive aspect of assembly oriented design vision. Central to this approach is the establishment and implementation of a complex and multiple viewpoints of product development addressing various stakeholders design and assembly planning points of view. By establishing such comprehensive relationships and identifying related relationships among several lifecycle phases, it is then possible to undertake the product design and assembly phases concurrently. Specifically, the proposed work and its application enable the management of product relationship information at the interface of product-process data management techniques. Based on the theory, models and techniques such as described in previous work, the implementation of a new hub application called PEGASUS is then described. Also based on web service technology, PEGASUS can be considered as a mediator application and/or an enabler for PLM that externalises product relationships and enables the control of information flow with internal regulation procedures. The feasibility of the approach is justified and the associated benefits are reported with a mechanical assembly as a case study. (C) 2013 Elsevier B.V. All rights reserved.

Decision support methods for closed-loop conceptual design

Jongho Shin

The dissertation deals with closed-loop product lifecycle management (PLM) approaches for the product conceptual design improvement using gathered data during the usage period of a product. In closed-loop PLM, the data generated in each lifecycle phase can be shared in different lifecycle phases and used for various objectives such as design, maintenance, recycle, and so on. Among them, we focus on the information flow from the middle of life (MOL) phase to the beginning of life (BOL) phase. From the MOL phase, the product usage data is gathered and transferred to the BOL phase. The transferred data should be transformed into suitable information (e.g. contextualized usage data such as failure rate, mean time between failure, and etc.) and knowledge (e.g. design modification suggestions for product improvement) for the conceptual design activity of the BOL phase. This dissertation provides a procedure and related methods for the transformation of data into information and knowledge. For this, we develop a product usage data transformation method consisting of three steps: 1) evaluation of a used component/part status, 2) correlation between a used component/part status and design parameters, and 3) estimation of product improvement cost investment for possible modifications of required design parameters. In the first step of our method, we define an index value which indicates the degree of performance degradation of used components/parts functions considering the historical change of the performance degradation over time. In this index, the historical change of the performance degradation is considered as three characteristics: criticality, abnormality, and severity. In the second step of our method, we correlate the evaluated performance degradation of component/part function and the field data which consists of the working environment and operational setting during product operation. To this end, we follow several sub-steps. In these sub-steps, we use various methods such as a function structure model, a degradation scenario, a clustering technique, and a relation matrix. To analyze product functions and define degradation scenarios, we build and use a function structure model. The clustering technique is used to classify the field data by product status. The relation matrix is used to calculate the importance rate of the product functions and the product design parameters. The importance rate helps engineers to recognize which functions are critical in performance degradation and which design parameters are important from the viewpoint of the performance degradation. In the last step of our method, the found design parameters and their importance rates are used to estimate the cost investment for product design modification during the conceptual design phase. To do this, an extended house of quality (HOQ) is developed and a mixed integer non-linear programming (MINLP) formulation is proposed. To solve the problem of the cost investment estimation in a reasonable time, we provide three heuristic algorithms to solve the MINLP problem in a reasonable time. During the explanation of our method, we use two cases (turbocharger and locomotive) to show the validity of our method. From the application of our method into the case studies, we recognize critical design parameters (compressor wheel shape and the number of compressor wheel blades for turbocharger, and the diameter of brake cylinder for the locomotive) to be modified for the product improvement. An estimation of the required cost investment to modify these critical design parameters is calculated by the solution of the MINLP.

EPFL2009

A decision support method for product conceptual design considering product lifecycle factors and resource constraints

Jongho Shin, Paul Xirouchakis

In general, it is difficult to select a satisfactory product concept because the information in the early stage of design process is subjective, qualitative, and even uncertain to design engineers. The correlations among engineering characteristics for a product concept also increase the complexity of conceptual design. Moreover, it becomes important to consider not only customer requirements but also product lifecycle requirements. In spite of these problems, the resources that can be allocated in the product development are limited so that a company should select the most satisfactory product concept within its available resources. Therefore, it is useful to develop a new method for efficiently supporting conceptual design under this complex design environment. To this end, this study proposes a decision support method with extended house of quality (HOQ). With the proposed method, the best product concept and the associated investment allocation can be decided concurrently under consideration of product lifecycle factors and resource constraints. As a mathematical model combined with the extended HOQ, a mixed integer nonlinear programming model is defined and three heuristic search algorithms are developed. To show the usefulness of the proposed algorithms, a case study and computational experiments are introduced.

Springer Verlag2011

Industrial challenges in managing product development knowledge

Myrna Fatima Flores Pineda

To systematically create and share product development knowledge creates challenges for engineering companies. This paper presents an extensive study regarding the process of identifying such challenges in managing product development knowledge from the perspective of designers and engineers. This research is part of the LeanPPD, a project funded by the EU-PF7 (www.leanppd.eu), to address the need of European manufacturing companies for a new model, which extends beyond lean manufacturing and incorporates lean thinking into the product design and development process. A rigorous research methodology has been employed, which included the use of questionnaires and focused interviews with key informants from industry, involving forty-two product development engineers from nine different companies. The most significant concerns raised during the study concerned knowledge life cycle activities, product development environment and management. Thirty-eight challenges were identified, classified and discussed in order to provide the knowledge management community with practical evidence, and also to inform future research directions in managing product development knowledge. (C) 2014 Elsevier B.V. All rights reserved.

Elsevier2014

Decision support methods for closed-loop conceptual design

Jongho Shin

EPFL2009