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Balancing Commonality and Performance within the Concurrent Design of Multiple Products in a Product Family

Authors:
Timothy W. Simpson at Pennsylvania State University
Timothy W. Simpson
Carolyn C Seepersad at University of Texas at Austin
Carolyn C Seepersad
Farrokh Mistree at University of Oklahoma
Farrokh Mistree
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Abstract

Product family design involves the concurrent design of multiple products based on a common product platform to satisfy a variety of markets. The success of the resulting product family relies heavily on properly balancing the commonality of the product platform with the individual product performance within the product family. To help resolve this tradeoff, we present the Product Variety Tradeoff Evaluation Method for assessing alternative product platform concepts with varying levels of commonality. Two examples are presented to demonstrate the proposed method at both the detailed and the early stages of design. The redesign of a planetary gear transmission for a family of four cordless drills demonstrates the use of the method in the detailed stages of design, while the design of a family of three General Aviation Aircraft demonstrates the use of the method in the preliminary stages of design. The emphasis in this paper is on the effectiveness of the proposed method in evaluating this tradeoff and not on the results of the examples, per se.
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TO CITE THIS WORK:
Simpson, T.W, Seepersad, C.C. and Mistree, F., 2001, “Balancing Commonality and
Performance within the Concurrent Design of Multiple Products in a Product Family," Concurrent
Engineering Research and Applications, vol. 9, no. 3, pp. 177-190.
... A metric to assess the individual performance of each variant is important to be defined as well. Within this context, Simpson et al. [81,88] proposed a Product Variety Index which evaluates the trade-off between commonality and individual performance compromises. ...
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... From the perspective of marketing, marketing managers focus on portfolio optimization considering customer preferences and purchase behaviors with the objective of maximizing market share, profit, or customer utility (Green and Krieger, 1985;. In the engineering field, production managers pay more attention to the costs and flexibility issues associated with product portfolio and aim to reduce the engineering costs at the stage of manufacturing (Simpson et al., 2001;Gauss et al., 2021). Jiao and Zhang (2005) examined the PPP problem with customer and engineering interaction, and formulated a maximizing expected shared surplus model for leveraging both the marketing and engineering concerns. ...
... These algorithms include GAs (Alexouda and Paparrizos, 2001;Balakrishnan et al., 2004;Balakrishnan et al., 2006;Balakrishnan and Jacob, 1995;Balakrishnan and Jacob, 1996;Steiner and Hruschka, 2003), evolutionary algorithms (Alexouda, 2004;Alexouda, 2005), ant colony optimization (Albritton and McMullen, 2007), PSO (Tsafarakis et al., 2011;Tsafarakis et al., 2013), SA (Tsafarakis, 2016), differential evolution (Tsafarakis et al., 2020), Tabu search , imperialist competitive algorithm (Liu et al., 2021), and clonal selection algorithms (Pantourakis et al., 2021). In the engineering field, most product line design literature deals with costs and flexibility issues in platform management, in which the balance between the commonality of the product platform and the engineering performance of product variants is linchpin (Ali et al., 2021;D'Souza and Simpson, 2003;Liu et al., 2011;Simpson et al., 2001;Thevenot et al., 2007;Thevenot and Simpson, 2006;Du et al., 2019). ...
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  • Jul 2022
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... Chen et al. [93] used RCEM to evaluate design alternatives and develop top-level specifications for high-speed civil transport aircraft. Simpson et al. [94] proposed a product variety tradeoff evaluation method for assessing alternative product platform concepts with varying levels of commonality-the challenge lies in balancing the commonality and performance of products in a product family. The authors verified the method using gear transmission and general aviation aircraft design. ...
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