A Decision Tool for Product Configuration Designs based on Sustainability Performance Evaluation

Transcription

1 Advanced Materials Research Vol. 903 (2014) pp (2014) Trans Tech Publications, Switzerland doi: / A Decision Tool for Product Configuration Designs based on Sustainability Performance Evaluation Mohd Fahrul Hassan 1, a, Muhamad Zameri Mat Saman 2,b, Safian Sharif 2,c and Badrul Omar 1,d 1 Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Batu Pahat, Johor, Malaysia 2 Department of Manufacturing & Industrial Engineering, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia a fahrul@uthm.edu.my, b zameri@fkm.utm.my, c safian@fkm.utm.my, d badrul@uthm.edu.my Keywords: Product design and development, configuration design, sustainable products, Analytic Hierarchy Process (AHP), sustainability evaluation Abstract. In recent years, evaluating sustainability performance of designed products has been demanded by legislations before manufacturing the products. These legislations are aimed to force manufacturers to implement sustainable end-of-life strategies in the product development phase. Although a number of studies have been conducted on integrating sustainability elements during product design and development, a tool to assist product designers in making final decision of the designed products with the most sustainability content among the alternative configuration designs has not been comprehensively investigated. In this paper, a decision tool is proposed in order to fulfill those needs. The sustainability performance is measured using Analytic Hierarchy Process (AHP) by providing a weightage of sustainability metrics throughout the total product s life-cycle. An example of an armed chair is used to demonstrate this tool. This decision tool provides a new and comprehensive basis for developing sustainable products in the future. Introduction Consideration of sustainability into the engineered, discrete and physical products over their life-cycle stage may cause positive impacts especially to environment, economy and society. The sustainable products are defined as products that are produced following sustainability principles and are sustainability-compliant throughout their entire life-cycle, from conception to end-of-life [1]. The effective ways in order to achieve those needs is by implementing sustainability consideration during the product design and development process [2, 3]. The product design and development for improved environmental performance has many expressions including design for environment, ecological design, environmental design, environmentally conscious design, environmentally responsible design, socially responsible design, sustainable product design, sustainable product development, green design and life-cycle design [4]. A group of sustainability elements that recently discussed in the literature is investigated and implemented to deal with this issue. Sustainability is defined generally in many ways and has different meanings to different people which the term is more recognized as sustainable development. The sustainable development which was introduced by the Brundtland Commission (1987) [5] is defined as development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Sustainable product design is the integration of sustainability in product design and development which as it integrates societal aspect of the product s life-cycle alongside environmental and economic consideration, so-called as triple bottom line (TBL) [6]. Fiksel et al. [7] in their early work presented a set of product sustainability indicators for evaluating products under environmental, societal and economic considerations. In the very recent years, Jawahir et al. [8] presented that these major considerations of sustainability needs to be considered throughout the total product s life-cycle of four stages from pre-manufacturing, manufacturing, use to post-use in order to develop sustainable All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of TTP, (ID: , Universiti Tun Hussein Onn Malaysia, Batu Pahat, Malaysia-25/02/14,14:40:31)

2 Advanced Materials Research Vol products and measuring the sustainability content, as well. Furthermore, to be a more comprehensive and complete depiction, Joshi et al. [9] introduced the 6R concept (reduce, reuse, recycle, recover, redesign, and remanufacturing) instead of the 3R concept (Reduce, Reuse, and Recycle) to be included as end-of-life processing strategies, so that a perpetual product/material flow can be achieved and product s ecological footprint can be minimized. Evaluating sustainability performance of a product across its total life-cycle is one of the objectives in this study. Some researchers have presented different approaches for improving the initial design of products with more sustainable options before selecting the final design. Gehin et al. [10] presented tools to implement sustainable end-of-life strategies in the product development phase to help designers make optimal decisions while designing a product by considering 3R strategies: Reuse, Remanufacture and Recycle. Herrmann et al. [11] presented a framework of an evaluation of a product s end-of-life characteristics based on both product and process models, which is directly linked to a planning approach for the processes in the end-of-life phase. This approach uses a common data source for the product and process data in order to assess the relevant end-of-life aspects, to integrate the end-of-life phase into the conceptual design and to plan a simulation-based of disassembly systems. Devanathan et al. [12] presented semi-quantitative ecodesign tool for improved environmental performance using a combination of environmental life-cycle assessment, working knowledge model and visual tools such as quality function deployment (QFD), functional-component matrix and Pugh chart. Chu et al. [13] proposed a CAD-based approach that allows automatic variation of 3D product structure for reducing environmental impact during product s end-of-life by changing the combination of parts, selecting the assembly method and rearranging the assembly sequence. Genetic Algorithm (GA) is then applied to produce an optimal product structure from the design alternatives and systematically to lower assembly/disassembly costs, while complying with specified recycling and recovering rates. However, most of the previous studies only consider one or two major aspects of sustainability: environmental, economic, or societal aspect for evaluating product sustainability throughout the products entire life cycle stages, and does not incorporates the 6R concept simultaneously. Therefore, to overcome those deficiencies, this paper proposes a decision tool to assist product designers in making final decision of designed products by measuring sustainability content among product configuration designs before entering manufacturing stage. Analytic Hierarchy Process (AHP) is used in this study to evaluate product configuration designs by providing a weightage with regard to the identified sustainability metrics. Methodology The methodology integrates the sustainability elements in the conceptual design stage during selection of final design within a single framework. The proposed methodology is shown in Fig. 1. There have seven (7) stages and described as follows: Stage 1: Sustainability element is identified for easily searching sustainability metrics for measuring sustainability performance. The sustainability element includes; 1) Three bottom line (TBL) environmental, economic, and societal aspect; 2) Total product life-cycle stages, from pre-manufacturing, manufacturing, use, to post-use; and 3) The 6R concept (reduce, reuse, recycle, recover, redesign, and remanufacture). Stage 2: The weights of sustainability metrics are determined for easily measuring sustainability performance using AHP method. AHP is well-known as a multi-criteria decision making (MCDM) technique which was introduced by Saaty (1977) has attracted the interest of many decision makers in solving complex problems with multiple conflicting and subjective criteria by organizing thoughts, experiences, knowledge and judgments into a hierarchical framework, and guiding them through a sequence of pairwise comparison judgments [14].

3 386 Manufacturing Engineering Stage 1: Identify the sustainability elements and the sustainability metrics Stage 2: Determine the weights of each sustainability metric Stage 3: Define the product to be evaluated Stage 4: Extract the product into a basic component and generate alternative configuration designs based on morphological analysis theory Stage 5: Determine the weights of each alternative configuration design with regard to each sustainability metric Stage 6: Configure the basic components with desired configuration design into a complete product Stage 7: Calculate the product configuration sustainability score Fig. 1 Methodology Stage 3: The product to be evaluated is defined. This methodology is possible to be applied on a generic product, specifically to engineered, discrete and physical products. The target product also is not focused only a very new product, but existing products also can be selected in order to change the product attributes into a new sustainable manner. Stage 4: The defined product is extracted into a basic component and alternative configuration designs are generated using morphological analysis theory. The configuration designs are generated based on the form which develops from the function, and strongly depends on available materials and production methods. Stage 5: In this stage, one more evaluation is performed which the weight for alternative configuration designs with regard to the identified sustainability metrics are determined using AHP method. Stage 6: The basic components with desired configuration design are configured into a complete product. A number of product configuration designs are produced that depends on the number of generated alternative configuration designs. Stage 7: By configuring basic elements with desired configuration design into complete products, the product sustainability score is totally calculated. The sustainability performance of product configurations is indicated using scoring method, which 0 indicates the worst sustainability content meanwhile, 1 indicates the most sustainability content. Development of the Decision Tool Based on the above methodology, computer software based was developed to ease the evaluation process and facilitate the decision making as illustrated in Fig.2. Stage 1 to 2 in the methodology is implemented in the phase 1 of the decision tool. The 46 influencing factors which were introduced by Gupta et al. (2010) [15] are referred as the sustainability metrics in this study.

4 Advanced Materials Research Vol Fig. 2 Phase 1 of the decision tool In the phase 1, a product designer is required to set the desired weightage of sustainability that consists of TBL in the Step 1. In this example, the relative weights of TBL are set as balance which resulting in for each aspect as shown in Fig. 3. The relative weights for sustainability metrics over product s life-cycle are generated by multiplying the desired weights of TBL with the weighted sustainability metrics that obtained from the AHP calculation. The detail process for determining the weights of sustainability metrics using the AHP can be seen in Hassan et al. (2013) [16]. Based on these weights, the sustainability performance can be summarized in detail on which aspect has the highest concerned and the lowest concerned throughout the product s life-cycle stage. Fig. 3 Setting the desired weightage of sustainability As stated in the Stage 3, product to be evaluated is defined. In this example, an armed chair was used as a case study in order to illustrate the next process of the proposed methodology and the software developed for sustainability evaluation. The selection of the product is indicated in the phase 1 and clicks the Next button to go to the phase 2.

5 388 Manufacturing Engineering Fig. 4 shows the phase 2 of the decision tool. In the phase 2, the Stage 4 to Stage 7 are implemented. The detail process of the Stage 4 to Stage 5 can be seen in Hassan et al. (2013) [16]. The product designer is required to prioritize the product s part in the Step 2. In this example, the relative importance weights are set as balance which resulting in for each part. In the Step 3, selection of desired configuration design for each basic part is made by ticking the option button and configured into a complete product in the Step 4. The sustainability score of the selected product configuration is calculated in the Step 5. It can be summarized that by selecting Round shape with polypropylene material for Back part, Square shape with polypropylene material for Seat part, Tri-angle shape with plywood material, and U-shape with stainless steel material for Base part, the product configuration sustainability score over product s life-cycle is (pre-manufacturing), (manufacturing), (use), and (post-use). Meanwhile, the total sustainability score is Conclusions Fig. 4 Sustainability evaluation of the armed chair in the phase 2 In this paper, a decision tool for evaluating sustainability performance of product configuration designs before manufacturing the designed product is presented. The AHP technique is used for providing weights of sustainability metrics and also weights for configuration designs with regard to the sustainability metrics. A case study of an armed chair is performed to illustrate the proposed methodology and the developed software. This software can be used by product designers and manufacturers in making decision in order to select the most sustainable configuration among several possible configurations. This software provides a new and comprehensive basis for developing sustainable products in the future. Acknowledgements The authors wish to thank the Ministry of Higher Education Malaysia (MOHE), UTHM, UTM and Research Management Center, UTM for the financial support to this work through the Research University Grant (RUG) funding number Q.J J29 and QJ H43.

6 Advanced Materials Research Vol References [1] D. Maxwell, R. van der Vorst, Developing sustainable products and services, Journal of Cleaner Production. Vol.11 (2003) [2] G. Howarth, M. Hadfield, A sustainable product design model, Materials and Design 27. (2006) [3] S. Byggeth, G. Broman, K. Robert, A method for sustainable product development based on a modular system of guiding questions, Journal of Cleaner Production 15, (2007) [4] K.M. Lee, P.J. Park: EcoDesign: Best Practice of ISO14062, Eco-product Research Institute (ERI), Ajou University, Korea [5] Bruntdland Commission Report. Our Common Future: From one earth to one world, (IV), Oxford, UK, Oxford University Press, World Commission on Environment and Development, 22-23, [6] M. Charter, U. Tischner, Sustainable Solution: Developing Products and Services for the Future, Sheffield, UK, Greenleaf Publishing, [7] J. Fiksel, J. McDaniel, D. Spitzley, Measuring product sustainability, Journal of Sustainable Product Design 6. (1998) [8] I.S. Jawahir, K.E. Rouch, O.W. Dillon, Jr., K.J. Joshi, A. Venkatachalam, I.H. Jaafar, Total life-cycle considerations in product design for sustainability: A framework for comprehensive evaluation (Keynote paper), Proc. TMT 2006, Lloret de Mar, Barcelona, Spain. (2006) [9] K. Joshi, A. Venkatachalam, I.H. Jaafar, I.S. Jawahir, A new methodology for transforming 3R concept into 6R for improved sustainability: Analysis and case studies in product design and manufacturing, Proc. IV Global Conf. On Sustainable Product Development and Life Cycle Engineering: Sustainable Manufacturing, October 3-6, Sao Paulo, Brazil. (2006). [10] A. Gehin, P. Zwolinski, D. Brissaud, A tool to implement sustainable end-of-life strategies in the product development phase, Journal of Cleaner Production. Vol.16 (2008) [11] C. Herrmann, A. Frad, T. Luger, Integrating the end-of-life evaluation and planning in the product management process, Progress in Industrial Ecology An International Journal. Vol.5 (2008) [12] S. Devanathan, P. Koushik, F. Zhao, K. Ramani, Integration of sustainability into early design through working knowledge model and visual tools, Proceedings of the 2009 International Manufacturing Science and Engineering Conference (MSEC2009), October 4-7, West Lafayette, IN, USA (2009). [13] C-H. Chu, Y-P. Luh, T-C. Li, H. Chen, Economical green product design based on simplified computer-aided product structure variation, Computers in Industry. Vol.60 (2009) [14] H. Al-Barqawi, T. Zayed, Infrastruture management: Integrated AHP/ANN model to evaluate municipal water mains performance, Journal of Infrastructure Systems. (2008) [15] A. Gupta, R. Vangari, A.D. Jayal, I.S. Jawahir, Priority evaluation of product metrics for sustainable manufacturing, Proceedings of the 20th CIRP Design Conference, Nantes, France. (2010) [16] M.F. Hassan, M.Z.M. Saman, S. Sharif, B. Omar, Evaluation of sustainability performance of product design element concepts using Analytical Hierarchy Process, Applied Mechanics and Materials. Vol. 315 (2013)