An Innovative Approach to Enhancing the

sustainability Article

An Innovative Approach to Enhancing the Sustainable Development of Japanese Automobile Suppliers Chia-Nan Wang 1 , Ying-Fang Huang 1 , Thi-Nham Le 1, * and Thanh-Tuan Ta 2 1

2

*

Department of Industrial Engineering and Management, National Kaohsiung University of Applied Sciences, No. 415 Chien Kung Road, Sanmin District, Kaohsiung City 80778, Taiwan; [email protected] (C.-N.W.); [email protected] (Y.-F.H.) Foxconn Electronics Inc., Bac Ninh Province 790000, Vietnam; [email protected] Correspondence: [email protected]; Tel.: +886-7-8215888 (ext. 107); Fax: +886-7-8215866

Academic Editor: Tin-Chih Toly Chen Received: 6 March 2016; Accepted: 25 April 2016; Published: 28 April 2016

Abstract: The Japanese automobile industry has been hit sharply by the economic downturn of recent decades. The rise in costs and decline in sales have led to serious problems in the auto industry. In order to address these issues, most companies engage in downsizing and redesigning production operations. It is crucial to investigate the time wasted by replacing assembly boards occurring in manufacturing lines. Therefore, the aim of this study was to provide an integrated approach, Teoriya Resheniya Izobreatatelskih Zadatch (TRIZ), to providing efficient solutions for the automobile industry. The first step of this methodology is to detail the technical problems using the Function and Attribute Analysis (FAA) model. Secondly, a contradiction matrix and the inventive principle were applied to find the solutions. In this study, an auto part supplier named Sumi-Hanel located in Hanoi, Vietnam, was taken as a case study; the empirical results showed that waste time had been reduced to 67%, nearly 8400 square meters was saved, and a 20% cost reduction was achieved by reusing old frames. The research proves that the combination of TRIZ and lean manufacturing successfully increases production performance and reduces waste due to technological advancements. Keywords: lean manufacturing; TRIZ; automobile industry; function and attribute analysis model; contradiction matrix

1. Introduction Japan’s automobile industry has made a huge impression; it is ranked very highly in terms of key export products and makes a remarkable contribution to Japan’s core economy. Japanese automakers craft better quality products with fewer defects and have the world’s highest reputation. The country is home to leading manufactures that have introduced highly competitive cars with advanced hybrid and fuel-saving technologies, namely Toyota, Honda, Daihatsu, Nissan, Suzuki, Isuzu, etc. [1]. Automobile manufacturing is an integrated industry because it relies on many supporting industries, referred to as automobile system suppliers, in order to produce a diversity of materials and components. Auto-related industries employed a total of 5.5 million people in 2014, covering an extremely wide range of industries from materials supply and vehicle production to sales, servicing, and freight shipping [2]. Japan is the third largest automobile producer in the world, with export of motor vehicles recorded at 4,578,078 units, a 49.3% share of the total manufacturing volume in 2015—and this is a production increase after two years of downturn [3]. However, annual vehicle sales in Japan today are lower than they were 10 years ago, suggesting a saturated domestic market and a backdrop of long-term economic problems. Figure 1 gives a complete picture of motor vehicle exports over the past decade; Sustainability 2016, 8, 420; doi:10.3390/su8050420

www.mdpi.com/journal/sustainability

Sustainability 2016, 8, 420 Sustainability 2016, 8, 420

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long-term economic problems. Figure 1 gives a complete picture of motor vehicle exports over the past decade; it reflects the automotive industry’s fluctuation, strongly affected by global economic it reflects the automotive industry’s fluctuation, strongly affected by global economic crisis during crisis during 2008–2010 [2]. Most companies today are still struggling to climb out of the trough of 2008–2010 [2]. Most companies today are still struggling to climb out of the trough of recession in order recession in order to retain market share and not be surpassed by other emerging economies such as to retain market share and not be surpassed by other emerging economies such as the Chinese and the Chinese and Indian automobile industries [4,5]. Japan’s past successes and current challenges are Indian automobile industries [4,5]. Japan’s past successes and current challenges are most apparent in most apparent in the nation’s automakers, so the country has accordingly attracted the attention of the nation’s automakers, so the country has accordingly attracted the attention of many researchers, many researchers, both academicians and practitioners, as the economic situation can have serious both academicians and practitioners, as the economic situation can have serious implications on the implications on the further development of the automobile industry [6–8]. further development of the automobile industry [6–8].

0

4,578,078

4,465,624

4,674,633

4,803,591

4,464,413

4,841,460

6,727,091 3,616,168

2,000,000

6,549,940

4,000,000

5,053,061

Export Units

6,000,000

5,966,672

8,000,000

160 140 120 100 80 60 40 20 0

Change (%)

Vehicle Exports

Year Export Unit

Change (%)

Figure 1. Motor vehicle exports. Figure 1. Motor vehicle exports.

During the stagnation of the Japanese economy for over a decade, Toyota Motor Company During the stagnation of the Japanese economy for over a decade, Toyota Motor Company retained about 50% of its global production in Japan and ranked as the world’s most successful retained about 50% of its global production in Japan and ranked as the world’s most successful automaker, totally outperforming its competitors in terms of quality products and reliable services automaker, totally outperforming its competitors in terms of quality products and reliable services by applying lean production [9,10]. Lean manufacturing has been used in a variety of industries by applying lean production [9,10]. Lean manufacturing has been used in a variety of industries as a as a creative method that eliminates waste while increasing productivity [11,12]. Companies can creative method that eliminates waste while increasing productivity [11,12]. Companies can predict predict short supply lines based on a lean method that delivers small batches of components to the short supply lines based on a lean method that delivers small batches of components to the assembly assembly line steadily without interruption [13]. Lean manufacturing provides ideas for companies to line steadily without interruption [13]. Lean manufacturing provides ideas for companies to solve solve problems and correct product specifications as required. This business model helps automakers problems and correct product specifications as required. This business model helps automakers reduce inputs and assembly costs, and produce better quality products. Today’s leading companies reduce inputs and assembly costs, and produce better quality products. Today’s leading companies like Toyota, Ford, Dell, and FedEx are creating their business models based on lean thinking and are like Toyota, Ford, Dell, and FedEx are creating their business models based on lean thinking and are gaining significant benefits that continue to enhance their success in the global market [14,15]. gaining significant benefits that continue to enhance their success in the global market [14,15]. As an extension of the Japanese automobile industry, the auto parts industry depends on consumer As an extension of the Japanese automobile industry, the auto parts industry depends on demand for vehicles in order to succeed. The automotive industry crisis of 2008–2010 was a part consumer demand for vehicles in order to succeed. The automotive industry crisis of 2008–2010 was of a global recession; it seriously affected automakers and their supply chains. Production cuts by a part of a global recession; it seriously affected automakers and their supply chains. Production cuts automakers caused severe challenges for auto part manufacturers. After the influence of the financial by automakers caused severe challenges for auto part manufacturers. After the influence of the downturn and decline of sales, industry analysts had suggested that suppliers should run at least financial downturn and decline of sales, industry analysts had suggested that suppliers should run 80% capacity compared to original production in order to make a profit; in fact, they only reached at least 80% capacity compared to original production in order to make a profit; in fact, they only 50%–60% production capacity in 2009 [16]. Many companies have faced serious problems of excess reached 50%–60% production capacity in 2009 [16]. Many companies have faced serious problems of labor, overcapacity, scarce resources, and the rising cost of input. In order to cope with these issues, excess labor, overcapacity, scarce resources, and the rising cost of input. In order to cope with these most firms are required to further restructure operations and downsize product lines. However, the issues, most firms are required to further restructure operations and downsize product lines. renewal process for an industry is never easy, and might be affected by internal innovation capability However, the renewal process for an industry is never easy, and might be affected by internal and external linkage according to automakers’ requirements and different viewpoints in today’s innovation capability and external linkage according to automakers’ requirements and different fiercely competitive globalized world. viewpoints in today’s fiercely competitive globalized world.

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As an original equipment manufacturer (OEM), Sumi-Hanel, the wiring system supplier for Japanese automakers, faced lots of difficulties during the automobile industry crisis and Japan’s recession. The reduction in sales demand made many conveyors run at low production. In order to eliminate the waste of human resource and production costs, two conveyors were combined into one. However, the combination meant the average efficiency in 2009 was only 80%. This means that efficiency dropped by 15% compared to the previous year, according to the report of the Department of Engineering. Sumi-Hanel has focused on improving production by applying the lean manufacturing model for many years; however, lean tools seem to be not scientific enough to find and solve realistic problems of inefficient factors. TRIZ methodology has been applied in many automobile companies in various sections of manufacturing activities. However, each sector is always impacted by excess production costs. Therefore, this research employs the application by combining TRIZ and lean manufacturing to achieve cost improvement and technical innovation by using TRIZ methodology under lean manufacturing concepts to find all problems occurring in every assembly line. Finally, replacing the assembly board was investigated as the main reason. This paper defines the problem existent in the replacing assembly board using the Function and Attribute Analysis (FAA) model, then engages the contraction matrix and inventive principle to find and solve problems, which enhances the production efficiency for the firm by reducing use in the manufacturing process and ensuring the highest standards of quality and safety of auto parts. TRIZ was developed in 1946 by Altshuller, a Russian scientist who initiated the theory of inventive problem solving [17]. It is an effective method for analyzing problems and developing innovative solutions. TRIZ has the ability to not only be prepared for methods, but also to create them. Firstly, the paper proposes an innovative approach that integrates TRIZ into lean concepts to apply to manufacturing processes in the automotive industry. Finally, this research provides a valued method for managers with regards to manufacturing performance, along with insight into the best pathways for companies to improve the sustainable manufacturing by using TRIZ and lean manufacturing. The aim of this study is to provide an integrated TRIZ approach into lean thinking to generate innovative solutions for the automobile supplier, reduce the time of changing board, and drive costs down for setting up new conveyors. Sumi-Hanel, a supplier of Japanese automobile parts, was taken as an example. The goal of the research is to minimize the waste time in replacing the assembly board and increase productivity. Inventive principles and a contradiction matrix were used in this study as the concept of innovative system analysis. The scope of this research focuses on improving productivity. Therefore, the authors only compare the results before and after improvement. This is just the first step of improvement. However, continuously enhancing productivity for sustainable development is necessary by applying more methods in the future. The rest of this paper is organized as follow. Section 2 begins with background, introducing lean manufacturing and giving a general overview of TRIZ. Section 3 presents a case study and discussion. Some conclusions are made in Section 4. 2. Background 2.1. Lean Manufacturing Lean manufacturing, also known as lean production, is a set of tools and methodologies intended to eliminate all waste in the entire system [18]. Today, lean manufacturing is adopted in a variety of industries in order to significantly reduce inventory in the supply chain, increase productivity, and improve the quality of the products. Lean manufacturing focuses on investigating defects and wastage, cycle times, inventory levels, labor productivity, utilization of equipment and space, flexibility, and output. The main outcomes of lean manufacturing are a reduction in time waste and unnecessary resources due to machine setup, product changeover, or long production lead times. The main benefits of lean manufacturing are lower production costs, increased output, and higher quality products [19].


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Lean manufacturing refers to the elimination of any kind of waste that diminishes value for manufacturers and businesses. Lean methods has been developed much of its use by Japanese automobile manufacturer Toyota. The Toyota Production System manual, written by Taiichi Ohno, published for the second time in 1994, explained the foundation of lean manufacturing [20]. These principles guided Japanese companies to be successful and become the world leaders in the automobile industry. Ohno identified seven main types of waste: over-production, defects, inventory, transportation, waiting, motion, and over-processing [20]. The lean production system ensured companies’ position as industry leaders, and its principles were adopted by companies in many countries. Some applied innovation researchers have put much effort into studying Toyota’s performance in order to identify the realistic outcomes of lean manufacturing. It can be pointed out that the creative methods of Toyota production system (TPS) are not just the use of inventory reduction, setup reduction, and cost reduction. Rather, the backbone of TPS is integration of all solutions in the entire system to optimize the overall manufacturing process. Womack and Jones developed the lean concept further based on two famous books, The Machine that Changed the World and From Lean Production to the Lean Enterprises, in the 1990s [21,22]. They studied 90 automobile assembly factories in 17 countries to understand how the Japanese succeed in manufacturing. By applying lean manufacturing, the firms improved production by focusing on the elimination of all waste. Kamath and Liker (1994) indicated that Toyota and other Japanese automakers set clear and understandable goals for their suppliers based on their capacity and mutual alignment [23]. Needless to say, few manufacturers have imitated Toyota successfully, even though the firm has announced its technical practices. It is clear that the secret of Toyota’s success is based on tight principles of industrial engineering, namely simplification, standardization, and systematization, which are supported by scientific requirements, and combine with innovative aspects to achieve waste reduction and cost reduction while simultaneously increasing outputs. Therefore, in order to implement the lean approach, it is necessary to undertake an in-depth study of companies following the fundamental principles of TPS over time. 2.2. Theory of Inventive Problem Solving (TRIZ) 2.2.1. A General Overview of TRIZ TRIZ developed extensively in the Soviet space and defense industries during World War II beginning in 1946; it then began to popularize and further developed in countries all over the world in the following decades [17]. Today TRIZ has been used by many leading companies such as Ford, GM, Intel, and Xerox in order to enhance their global competitiveness. Global Samsung electronics recovered from the verge of bankruptcy after applying TRIZ, which helps to transform unidentified situations by solving technical problems and securing core patents [24,25]. TRIZ suggests strategies and patterns for resolving contradictions in both time and space. Although originally developed for technical applications, today TRIZ has gradually developed to generate breakthrough ideas for the manufacturing and service industries. TRIZ is an undoubtedly powerful problem solving method that consists of technical evolution, applying scientific methods in order to get the best results without harming the system [26]. TRIZ gives creative access to the knowledge and the best innovative experience of technology in the world. TRIZ is designed to carry out and add structure to natural creativity rather than replace it. It allows researchers to define and then solve any given problem in the system. TRIZ aims to find problems and solve those problems—whether they be technical or non-technical, simple or complex [26]. The advantage of TRIZ is that it actively transforms unwanted or harmful elements of a system into useful resources. There are different problem solving methods in TRIZ that can be used together or separately [27]. Generally, the innovative processes of TRIZ are to investigate realistic problems, define them, generalize ideas by finding the contradictions, and finally apply those general solutions to the specific problem [28].


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Mann, 2002 depict the systematic creativity process of the TRIZ method, which consists of four major steps as shown in Figure 2; the steps are: define, select tool, generate solution, and evaluate. These steps Sustainability 2016, 8, process 420 5 of 19 can be a looping until the solution is obtained [29].

Define

Select tool

Evaluate

Generate solutions

Figure Figure 2. Four Four major major “Systematic “Systematic Creativity” Creativity” steps.

The firststep, step,“define,” “define,” asks question: “what areproblems the problems in the system?” TRIZ The first asks the the question: “what are the in the system?” TRIZ provides provides five tools to define a problem: problem explorer, ideal final result, function and attribute five tools to define a problem: problem explorer, ideal final result, function and attribute analysis analysis (FAA), analysis, S-curvedand analysis, and mapping. perceptionThe mapping. The “select secondtool,” step,determines “select tool,” (FAA), S-curved perception second step, the determines the most appropriate solving techniques forproblem. the particular problem. In other most appropriate problem solvingproblem techniques for the particular In other word, different word, different problems need different different tools to solutions. generate different The third step, problems need different tools to generate The third solutions. step, “generate solutions,” “generate is the stageare where many by options generated byasusing TRIZ tools analysis, such as is the stagesolutions,” where many options generated using are TRIZ tools such substance-field substance-field analysis, technical contradiction/inventive principle, psychical contradiction, trends, technical contradiction/inventive principle, psychical contradiction, trends, resource, trimming, resource, trimming, knowledge/effect, ideal final result, and subversion analysis. Each tool also knowledge/effect, ideal final result, and subversion analysis. Each tool also includes many systematic includes many systematic steps generate solutions. The last step, identifies the ones best steps to generate solutions. Thetolast step, “evaluate,” identifies the“evaluate,” best solution from the solution from the ones generated in the third step. TRIZ offers two main ways to evaluate the result generated in the third step. TRIZ offers two main ways to evaluate the result of the solution, which are of the solution, which are quantity and quality. quantity and quality. In order to analyze problems, it is necessary to investigate the interactions between all the In order to analyze problems, it is necessary to investigate the interactions between all the components of an existing system. Therefore, in this paper, the FAA model is employed to find the components of an existing system. Therefore, in this paper, the FAA model is employed to find the focus and key problems as a first step [30]. The FAA model seeks out such problems by enabling focus and key problems as a first step [30]. The FAA model seeks out such problems by enabling researchers to more adequately describe the function analysis model in terms of how it is affected by researchers to more adequately describe the function analysis model in terms of how it is affected by changes in time. This model aims to identify in detail what the solution is expected to do and what changes in time. This model aims to identify in detail what the solution is expected to do and what its attributes will be. The FAA model not only advises researchers to understand the function of the its attributes will be. The FAA model not only advises researchers to understand the function of the components in the system but also encourages them to identify the harmful, ineffective, and components in the system but also encourages them to identify the harmful, ineffective, and excessive excessive relationships as well. relationships as well. Among the set of tools of the third step, the contradiction matrix and the 40 inventive principles Among the set of tools of the third step, the contradiction matrix and the 40 inventive principles are the most powerful tools, based on more than 400,000 patents analyzed by Altshuller, and it is a are the most powerful tools, based on more than 400,000 patents analyzed by Altshuller, and it is a very effective series of solutions for deriving new ideas for products [31]. The main findings of TRIZ very effective series of solutions for deriving new ideas for products [31]. The main findings of TRIZ are special processes for creating new concepts and tools as part of TRIZ to become familiar with are special processes for creating new concepts and tools as part of TRIZ to become familiar with parameters contained in the matrix in order to generate strategies and solve technical problems. parameters contained in the matrix in order to generate strategies and solve technical problems. 2.2.2. 2.2.2. Function Function and and Attribute Attribute Analysis Analysis Function Function and and attribute attribute analysis analysis (FAA) (FAA) is is one one of of the the three three essential essential elements elements of of the the problem problem definition process given by Mann, 2007 [30]. It represents a systematic method by which it is definition process given by Mann, 2007 [30]. It represents a systematic method by which it is possible possible to analyze the thedetailed detailedworkings workingsofofanan existing system. In terms of managing complexity, it ismost the to analyze existing system. In terms of managing complexity, it is the most comprehensive the three. A completed model presents an important lead knowing into knowing comprehensive of theofthree. A completed FAA FAA model presents an important lead into how how to approach the improvement of systems. Successful function analysis modeling demands a to approach the improvement of systems. Successful function analysis modeling demands a process process in which components are defined and then relationships between those components are in which components are defined and then relationships between those components are established. established. In terms defining the positivethe relationships, the method because in many In terms of defining theofpositive relationships, method is useful because is in useful many situations this will situations this will be the first time people have viewed the system under evaluation from such a be the first time people have viewed the system under evaluation from such a functional perspective. functional perspective. In terms of the subsequent identification of harmful, insufficient, or excessive relationships in the system, this is where the user is identifying where problems exist. A completed FAA model offers a link into the select part of the systematic creativity process. It is also a document that should live with the system as it evolves over time. The examining of FAA is through a simple system that consists of two components: an optical lens and an abrasive block used to polish the lens. The first step in producing a function analysis


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In terms of the subsequent identification of harmful, insufficient, or excessive relationships in the system, this is where the user is identifying where problems exist. A completed FAA model offers a link into the select part of the systematic creativity process. It is also a document that should live with the system as it evolves over time. Sustainability 2016, 8, 420 6 of 19 The examining of FAA is through a simple system that consists of two components: an optical lens and an abrasive block used to polish the lens. The first step in producing a function analysis picture of this system is to identify the components present. Each of the components is drawn in a picture of this system is to identify the components present. Each of the components is drawn in a box. box. The second step then involves thinking about what the functional relationships between the The second step then involves thinking about what the functional relationships between the different different components are and defining them as directional arrows between the component boxes. components are and defining them as directional arrows between the component boxes. The two The two steps are shown in Figure 3 [30]. The most important points here are to use simple noun– steps are shown in Figure 3 [30]. The most important points here are to use simple noun–verb–noun verb–noun relationships wherever possible, and to express the relationship using active verbs. These relationships wherever possible, and to express the relationship using active verbs. These rules will rules will help to tap into the solution parts of TRIZ more easily. help to tap into the solution parts of TRIZ more easily.

Figure 3. Function analysis analysis representation representation of Figure 3. Function of aa two-component two-component manufacturing manufacturing system. system.

2.2.3. Contradiction Matrix 2.2.3. Contradiction Matrix and and Inventive Inventive Principles Principles In is one In TRIZ, TRIZ, contradiction contradiction is one of of the the key key concepts concepts that that formulate formulate problems problems and and signpost signpost aa truly truly innovative provides 40 principles to solve both technical physical contradictions, innovative approach. approach.TRIZ TRIZ provides 40 principles to solve bothandtechnical and physical complete with descriptions of descriptions the detailed solutions contained in each principle inventive contradictions, complete with of the detailed solutions contained in [32]. each The principle [32]. principles are a central part of the TRIZ philosophy for problem solving and its tools help to The inventive principles are a central part of the TRIZ philosophy for problem solving and actually its tools eliminate compromise [33]. Given the[33]. importance eliminating the basic form help to actually eliminate compromise Given theofimportance of contradictions, eliminating contradictions, the for tool generation is a two-dimensional matrix, each side of which features the aforementioned basic form for tool generation is a two-dimensional matrix, each side of which features the parameters relevant to the solving of engineering, scientific, or design scientific, problems. or Thedesign resulting matrix aforementioned parameters relevant to the solving of engineering, problems. structure contains 39 structure different parameters. The contradiction matrix TRIZ is mainly composed The resulting matrix contains 39 different parameters. The of contradiction matrix of TRIZ of is 39 parameters and 40 inventive principles; the rows aim to present the improving feature parameters mainly composed of 39 parameters and 40 inventive principles; the rows aim to present the and the columns areparameters intended toand represent the worsening featuretoparameters, so aworsening pair of conflicted improving feature the columns are intended represent the feature parameters was composed [34]. Thus, the matrix element they correspond to is the 40 inventive parameters, so a pair of conflicted parameters was composed [34]. Thus, the matrix element they principles are able resolve principles these conflicts. Anable excerpt of the contradiction is shown in correspondthat to is the 40 to inventive that are to resolve these conflicts.matrix An excerpt of the Table 1 [30]. matrix is shown in Table 1 [30]. contradiction Table 1. An excerpt of the contradiction matrix. Table 1. An excerpt of the contradiction matrix. Worsening Improving

Worsening

Improving 1. Weights of moving object 2. Weight of stationary object ... 1. Weights of moving object 9. Speed 2. Weight of stationary object ... … 39. Productivity

2. Weight of 2. Weight of of Stationary Object Stationary Moving Object Object

1. Weights of 1. Weights Moving Object

…

23. Loss of 23. Loss Substance

of 3,Substance 5, 31, 35 5, 8, 13, 30

3, 5, 31, 35 10, 13, 28, 38 5, 8, 13, 30

2, 13, 28, 38 35, 26, 24, 37

...

28, 27, 15, 3

...

…

39. 39. Productivity

Productivity 3, 24, 35, 37 1, 15, 28, 35

3, 24, 35, 37 1, 15, 28, 35

10, 23, 28, 35

9. Speed 2, 13, 28, 38 10, 13, 28, 38 … Altshuller indicated that inventors usually have problems of technical contradiction and physical 39. Productivity 35, 26, 24, 37 28, 27, 15, 3 10, 23, 28, 35

contradiction when working on engineering projects [35]. Technical contradiction means that parameter “A” is changed when “B” is changed at the same time in a system. The problem with Altshuller indicated that inventors usually have problems of technical contradiction and technical contradiction can be solved through a contradiction matrix and the corresponding inventive physical contradiction when working on engineering projects [35]. Technical contradiction means principle. Figure 4 shows that parameter “A” can improve without worsening parameter “B” by that parameter “A” is changed when “B” is changed at the same time in a system. The problem with reducing the contradiction [36]. Conventional solutions usually propose a compromise between technical contradiction can be solved through a contradiction matrix and the corresponding the “improving” and “worsening” parameters. An innovative solution is achieved by resolving the inventive principle. Figure 4 shows that parameter “A” can improve without worsening parameter technical contradiction without compromise and tradeoff [37]. Physical contradiction means that the “B” by reducing the contradiction [36]. Conventional solutions usually propose a compromise contradiction relates to physical properties of an element, such as big and small, cold and hot, long between the “improving” and “worsening” parameters. An innovative solution is achieved by resolving the technical contradiction without compromise and tradeoff [37]. Physical contradiction means that the contradiction relates to physical properties of an element, such as big and small, cold and hot, long and short, etc. Altshuller proposed that the physical contradiction is normally managed by separation in time, separation in space, system transformation, and phase transition


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and short, etc. Altshuller proposed that the physical contradiction is normally managed by separation in time, separation in space, system transformation, and phase transition [35]. In others words, one problem exists in one conflict at least. It is a technology contradiction or a physical contradiction. Sustainability 2016, 8, 420 is resolved, it has produced a new technology as well. 7 of 19 When a contradiction

Figure 4. 4. Different Different to to compromise Figure compromise or or tradeoff: tradeoff: TRIZ TRIZ improvement. improvement.

2.3. Using TRIZ under Lean Manufacturing Concepts There are between TRIZ andand leanlean manufacturing concepts. Both of them aremany manygeneral generalsimilarities similarities between TRIZ manufacturing concepts. Both of them are aimed at improving the manufacturing process taking a significant timethe to are aimed at improving the manufacturing process by takingbya significant amount ofamount time to of define define thelook problems, forward tothe understand truth, solve those problems in order to problems, forwardlook to understand truth, and the solve thoseand problems in order to eliminate defects eliminate defects andofoptimize use of[38]. available resources purpose is tocoordination, bring about and optimize the use availablethe resources Its purpose is to [38]. bringIts about efficiency, efficiency, control of the natural environment. and controlcoordination, of the naturaland environment. solved, whereas lean However, TRIZ focuses on realistic resources in details that can be solved, toto find a feasible solution andand howhow to gotothrough with it. TRIZ manufacturing uses usesthe theentire entiresystem system find a feasible solution go through with it. sets up theup goal “perfection” to identify what what is going wrong with with the current system whilewhile lean TRIZ sets theof goal of “perfection” to identify is going wrong the current system manufacturing lookslooks at future ideas in order to to implement lean manufacturing at future ideas in order implementitsitsprocesses. processes.The Thepurpose purpose of of lean manufacturing is to eliminate waste, which is considered one of the main problems of an unhealthy addressed in in relation relation to to the the waste waste that that occurred occurred historically. historically. system. In TRIZ, the problems are fully addressed The similarities create overlap between TRIZ and lean manufacturing, whereas the differences are reason reasonfor formutual mutual assistance in order to the findbest thesolutions best solutions [39]. Therefore, paper assistance in order to find [39]. Therefore, this paperthis proposes a connected thinking with based TRIZ on ideas on lean implementation. Thebetween combination aproposes connected thinking with TRIZ ideas leanbased implementation. The combination TRIZ between and lean manufacturing results in a perfect methodtasks to accomplish theybeen mayable not and lean TRIZ manufacturing results in a perfect method to accomplish they may tasks not have have been able to tackle individually. to tackle individually. 3. CaseStudy Studyand andDiscussion Discussion 3. Case 3.1. Case Study Study 3.1. Case The of this this study study is is to to investigate investigate wasted wasted time time and and inefficiencies inefficiencies in in manufacturing manufacturing systems, systems, The aim aim of such This cannot such as as has has occurred occurred in in many many automobile automobile companies companies in in the the past past decade. decade. This cannot be be attained attained without taking into account specific issues in an individual company, especially for OEM without taking into account specific issues in an individual company, especially for OEM companies, companies, which cost of of finished finished products products through through unnecessary unnecessary factors. Therefore, this this study study which often often drive drive up up the the cost factors. Therefore, employs the example of Sumi-Hanel wiring system system supplier supplier in in order order to to focus employs the example of Sumi-Hanel wiring focus on on improving improving the the production efficiency of the replacing assembly board and accelerating manufacturing lines general. production efficiency of the replacing assembly board and accelerating manufacturingin lines in Through an explorative case study and the methods given in previous section, the paperthe willpaper be a general. Through an explorative case study and the methods given in previous section, good foundation for other companies in the sameinindustry that plan to that improve productivity will be a good foundation for other companies the same industry plantheir to improve their

productivity by applying a combined TRIZ and lean manufacturing approach. The findings of this study may be helpful for upcoming research in the area of sustainable manufacturing. Despite the effectiveness of this innovative approach, it is not easy to achieve success by combined TRIZ and lean manufacturing processes if companies only focus on tools and methods but overlook what problems might appear in the course of manufacturing. The truth is that one successful case might


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by applying a combined TRIZ and lean manufacturing approach. The findings of this study may be helpful for upcoming research in the area of sustainable manufacturing. Despite the effectiveness of this innovative approach, it is not easy to achieve success by combined TRIZ and lean manufacturing Sustainability 2016, 8, 420 8 of 19 processes if companies only focus on tools and methods but overlook what problems might appear in of manufacturing. truth However, is that onethis successful case could mightbe nota be generalized to notthe be course generalized to the overall The industry. exploration new direction for the overall However, this exploration could be a new direction for solving this kind of solving thisindustry. kind of industrial problem. industrial problem. The Japanese have a strong foothold in the automobile industry and they are pioneers in The Japanese have a strong foothold in automobile industry and In they are to pioneers in establishing external bases for automotive andthe auto-supporting industries. order make the establishing external bases for automotive and auto-supporting industries. In order to make the results as effective as possible, this paper selects the Sumi-Hanel Wiring System Co., Ltd. located in results effectiveisas possible, thisautomobile paper selects the Sumi-Hanel Wiring System Co.,wiring Ltd. located Hanoi, as Vietnam, Japan’s OEM largest supplier, which manufactures system in Hanoi, Vietnam, is Japan’s OEM automobile largest supplier, which manufactures wiring system products such as engine wiring systems, floor wiring systems, door wiring systems, and panel products such asfor engine wiring systems, floor wiring systems, door wiring systems,and andcustomers panel wiring wiring systems Suzuki, Toyota, and Daihatsu cars. The quantity of conveyors are systems for Suzuki, Toyota, and Daihatsu cars. The quantity of conveyors and customers are shown in shown in Table 2. Table 2. Table 2. Sumi-Hanel’s customers and types of conveyor. Table 2. Sumi-Hanel’s customers and types of conveyor.

Customers Type

Type

Customers

Floor Floor Engine Engine Panel Panel Door Door Total Total

Suzuki Suzuki 0 7 2 0 9

0 7 2 0 9

Toyota Toyota

13 133 3 1 1 11 1818

Daihatsu Daihatsu

0 01 1 0 0 00 11

Total Total

13 1113 11 3 3 11 2828

3.1.1. Assembly Assembly Flowchart flowchart 3.1.1. The assembly assembly flow flow chart chart is is shown shown in in Figure Figure 5. 5. The

Figure 5. The assembly flow chart. chart.

•

Step 1: Getting materials

Assembly tasks start with getting materials and wires from the material coordinator section, and the cutting and crimp section. Materials include connectors, clamps, clips, vinyl tubes, and poly vinyl chloride (PVC) sheets. Wires include single wire, shield wire, and twisted wire. These wires


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Step 1: Getting materials

Assembly tasks start with getting materials and wires from the material coordinator section, and the cutting and crimp section. Materials include connectors, clamps, clips, vinyl tubes, and poly vinyl chloride (PVC) sheets. Wires include single wire, shield wire, and twisted wire. These wires are cut Sustainability 2016, 8, 420 9 of 19 and crimped terminals. Sustainability 2016, 8, 420

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‚• •

Step 2: Sub assembly Step 2: Sub assembly In this this step, step,operators operatorsdirectly directly insert terminals of wires into connectors and them pressgently them insert thethe terminals of wires into connectors and press In this step, operators directly insert the terminals of wires into connectors and press them gently into the slots as shown in Figure 6. into the slots as shown in Figure 6. gently into the slots as shown in Figure 6.

Figure 6. Inserting terminal into connector. Figure 6. Inserting terminal into connector.

‚• •

Step 3: 3: On On assembly assembly manufacturing manufacturing lines, lines, operators operators manually manually attach attach clamps, clamps, PVC PVC sheets, sheets, and and Step Step 3:tubes On assembly manufacturing lines, operators manually attach clamps, PVC sheets, and vinyl and tape the wires together as shown in Figure 7. vinyl tubes and tape the wires together as shown in Figure 7. vinyl tubes and tape the wires together as shown in Figure 7.

Figure 7. The operators are working on a conveyor. Figure 7. The operators are working on a conveyor.

The quantity and quality of each assembly board in the manufacturing lines are based on the The quantity and quality of each assemblythe board in the manufacturing lines are based on on For the characteristics of products; all aim to eliminate sources of defects and errors in all The quantity and quality of each assembly board in the manufacturing lines areprocesses. based the characteristics of products; all aim to eliminate the sources of defects and errors in all processes. For example, there of areproducts; only 10 frames in to a long conveyor floor wiring systems, size characteristics all aim eliminate the of sources of defects and whereas errors inan allengine processes. example, there are only 10 frames in a long conveyor of floor wiring systems, whereas an engine size is short and contains frames in a in conveyor. The layout of an assembly conveyor is an shown in For example, there are 20 only 10 frames a long conveyor of floor wiring systems, whereas engine is short and contains 20 frames in a conveyor. The layout of an assembly conveyor is shown in Figure 8, which layoutinofa YGO engine conveyor. Inan one engine conveyor, first five size is short andintroduces contains 20the frames conveyor. The layout of assembly conveyor the is shown in Figure 8, which introduces the layout YGO engine conveyor. one operators start to work from 1ofto station 5, which has In responsibility for layingthe outfirst setsfive of Figure 8, which introduces thestation layout of YGO engine conveyor. In one engine engine conveyor, conveyor, the first five operators start to work from station 1 to station 5, which has responsibility for laying out sets of wires on the board andfrom inserting the1 waiting terminals the connectors. continue the line, the operators start to work station to station 5, whichinto has responsibility forTolaying out sets of wires wires on the board and inserting the waiting terminals into the connectors. To continue the line, the main assembly tasks are implemented by six final operators from station 6 to station 11. At these main assembly tasks are implemented fromthread stationthe 6 to station 11. stations, the operators attach the clamp, by fix six the final tape, operators bind the tape, grommet, etc. At these stations, the operators attach the clamp, fix the tape, bind the tape, thread the grommet, etc. • Step 4: Quality assurance • Step 4: Quality assurance In this step, lean manufacturing concepts are applied to raise the quality level. After all the


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on the board and inserting the waiting terminals into the connectors. To continue the line, the main assembly tasks are implemented by six final operators from station 6 to station 11. At these stations, the operators attach the clamp, fix the tape, bind the tape, thread the grommet, etc. ‚

Step 4: Quality assurance

In this step, lean manufacturing concepts are applied to raise the quality level. After all the assembly steps are done, products must be checked by six inspectors in order to ensure the quality Sustainability 2016, 8, 420 10 of 19 according to automakers’ standards. At the first visual checkpoint, two inspectors check the dimensions and color of the products by comparing with a master product. Two other inspectors undertake the undertake the circuit check; the use of other design currents for all the circuits has been determined, circuit check; the use of other design currents for all the circuits has been determined, and it is necessary and it is necessary to check that the limitation on voltage drops is met. The products are checked one to check that the limitation on voltage drops is met. The products are checked one last time before last time before packing at the second visual checkpoint. These inspectors must re-check the packing at the second visual checkpoint. These inspectors must re-check the components to make sure components to make sure the terminals and connectors are not broken after the previous steps and the terminals and connectors are not broken after the previous steps and the packing boxes are clean the packing boxes are clean and clear. and clear.

Figure 8. The layout layout of Figure 8. The of the the YGO YGO engine engine conveyor. conveyor.

3.1.2. Flexible Assembly 3.1.2. Flexible Assembly The The production production organization organization is is based based on on the the product product specifications. specifications. If If there there is is only only one one model model of of product in the conveyor, the production is continuous and simple. What happens when one conveyor product in the conveyor, the production is continuous and simple. What happens when one has severalhas products? production more complex. It iscomplex. crucial toItanalyze a system and define the conveyor several The products? The is production is more is crucial to analyze a system harmful, insufficient, and excessive relationships among them. Several types of board are required and and define the harmful, insufficient, and excessive relationships among them. Several types of board it sometimes to change the board. this paper, Suzuki engine conveyor was taken as are required takes and ittime sometimes takes time toInchange the the board. In this paper, the Suzuki engine an example. There are five product models in this conveyor: 36065-65K00, 36065-65K30, 36065-65K40, conveyor was taken as an example. There are five product models in this conveyor: 36065-65K00, 36065-65KA0, and 36065-65KC0. This conveyor has two typesThis of board: 36065-65K30, 36065-65K40, 36065-65KA0, and 36065-65KC0. conveyor has two types of board: ‚• ‚•

Type Type 11 is is used used for 36065-65K00, 36065-65K30, and 36065-65K40. There are 10 boards in this type. Type 2 is used in this this type. type. Type 2 is used for for 36065-65KA0 36065-65KA0 and and 36065-65KC0. 36065-65KC0. There There are are 20 20 boards boards in

There are two type of assembly board. Figure 9 shows that there are only 20 frames in one There are two type of assembly board. Figure 9 shows that there are only 20 frames in one round round conveyor and each frame can only bring one board. Therefore, 20 boards are used at the same conveyor and each frame can only bring one board. Therefore, 20 boards are used at the same time time and 10 boards are always in the waiting area. Figure 10 shows a schematic illustration of the and 10 boards are always in the waiting area. Figure 10 shows a schematic illustration of the board board and frame structure. In order to complete the assembly schedule shown in Table 3, the board and frame structure. In order to complete the assembly schedule shown in Table 3, the board ratio is ratio is changed daily by the leader; this example is for November. changed daily by the leader; this example is for November.

There are two type of assembly board. Figure 9 shows that there are only 20 frames in one round conveyor and each frame can only bring one board. Therefore, 20 boards are used at the same time and 10 boards are always in the waiting area. Figure 10 shows a schematic illustration of the board and frame structure. In order to complete the assembly schedule shown in Table 3, the board Sustainability 2016, 8, 420 11 of 19 ratio is changed daily by the leader; this example is for November.


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Figure 9. Layout of assembly board in conveyor.

Figure 10. 10. Schematic Schematic illustration illustration of of board board and and frame frame structure. Figure structure. Table 3. Assembly schedule of SUZUKI WAGON Table WAGON engine. engine. Wire Harness Board Wire Harness Board Type No. No. Type 36065-65K00 1 36065-65K00 1 36065-65K30 36065-65K30 11 36065-65K40 36065-65K40 11 36065-65KA0 36065-65KA0 22 36065-65KC0 22 36065-65KC0 Sub-Total Sub-Total Assembly board ratio Assembly board ratio (Type 1/Type 2) (Type 1/Type 2)

16 16 November November Tuesday Tuesday

17 17 November November Wednesday Wednesday

18 18 November November Thursday Thursday

19 19 November November Friday Friday

175 175

175 175

325 325 500 500

7/13 7/13

20 21 22 20 21 22 November November November November November November Saturday Sunday Saturday Sunday Monday Monday

325 500 500

500 500 500 500

175 175 125 125 200 200 500 500

75 75 100100 40 40 285285 500500

50 50 100 100 150 150 200 200 500 500

7/13 7/13

0/20 0/20

7/13 7/13

7/13 7/13

4/16 4/16

20 20 130 130 350 350 500 500 4/16

4/16

According to the schedule shown in Table 3, boards need to be replaced as follow: • On 18 November, seven boards must be replaced. According to the schedule shown in Table 3, boards need to be replaced as follow: • On 19 November, seven boards must be replaced. On boards must must be be replaced. replaced. •‚ On 18 21 November, November, seven three boards ‚ On 19 November, seven boards must be replaced. Therefore, 17 boards were replaced in total within a week. Four steps are required to replace the ‚ On 21 November, three boards must be replaced. assembly board: the replacing of the old board, preparation of the assembled frame, setting up another board on frame, andreplaced finally storing boards in awaiting area, are as shown in Figure 11. Therefore, 17the boards were in totalthe within a week. Four steps required to replace The minimum required time of replacement for each board is 15 min; therefore it takes 255 min in the assembly board: the replacing of the old board, preparation of the assembled frame, setting up total to replace 17 boards. At the same time, 153 products could be made in 15,300 s if 100 s are assumed to complete one product. In order to complete 500 products per day, the operators must work overtime. Sumi-Hanel has 28 conveyors, so several kind of boards are used on one conveyor with different kinds of products. The more types of board that are used, the more complex the conveyors are, which makes it difficult to control the quality of products. Table 4 gives a summary of


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another board on the frame, and finally storing the boards in awaiting area, as shown in Figure 11. The minimum required time of replacement for each board is 15 min; therefore it takes 255 min in total to replace 17 boards. At the same time, 153 products could be made in 15,300 s if 100 s are assumed to complete one product. In order to complete 500 products per day, the operators must work overtime. Sumi-Hanel has 28 conveyors, so several kind of boards are used on one conveyor with different kinds of products. The more types of board that are used, the more complex the conveyors are, which makes it difficult to control the quality of products. Table 4 gives a summary of product types and board types in the2016, Sumi-Hanel system, given by the internal department of production engineering. 12 of 19 Sustainability 8, 420

1

2

3

4

Figure Figure 11. 11. Changing Changing assembly assembly board. board. Table 4. Summary types and and board board types types used used by by Sumi-Hanel. Sumi-Hanel. Table 4. Summary of of product product types No.

No.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

NameName

Product Board Board Type Type Type 1 1 2 1 3 5 2 1 5 6 5 23 6 1 3 5 6 3 8 2 6 2 3 6 5 6 3 2 16 2 2 2 2 13 1 12 3 5 2 30 2 4 3 2 4 31 2 8 1 1 18 2 11 1 3 3 2 10 3 17 4 1 17 1 4 1 8 8 3 1 17 2 19 1 32 3 18 3

Product Type

Voxy Voxy/SaionVoxy EG Voxy/Saion EG YT2 EG YGO INST YT2 EG YGO EG YGO INST Wagon/YK1/Alto EG YGO1YGO EG EG YGO 2 EG Wagon/YK1/Alto EG Ipsum/Saion Floor Alto/YT2 Inst EG YGO1 Swift EG YGO 2 EG Isis/EK Wagon Floor Ipsum/Saion Floor Hijet EG VitzAlto/YT2 Floor Inst Vitz 5DR/Yaris Floor Swift EG Ractis Floor Belta/Vios Isis/EK Floor Wagon Floor YY3 EG Hijet EG YY3 EG new Vitz Floor EK Wagon Door Move EG Vitz 5DR/Yaris Floor Premio Floor/Yaris EU Floor Ractis Floor Highlander Floor Highlander/Tundra Belta/ViosInst Floor Isto/Vios Floor YY3 EG Yaris Floor 630LYY3 FloorEG new 640L EKFloor Wagon Door

Move EG Premio Floor/Yaris EU Floor Highlander Floor Highlander/Tundra Inst Isto/Vios Floor

1 3 6 23 6 8 6 6 16 13 12 30 3 31 18 11 10 17 17 8 3 17 19 32 18 10 16 36

Total Total Total Board Total Frame Board Frame 12 12 1224 12 12 2420 12 20 20 2020 20 20 20 2040 20 20 20 2024 20 24 20 4028 20 14 20 2440 20 14 2418 20 28 14 2816 14 10 10 4016 20 10 10 1814 14 10 10 2813 14 14 1619 10 18 14 1616 10 10 20 1020 10 28 14 1414 10 14 14 1328 10 26 14 1914 14 14 1814 14 14 14 14 16 10 20 20 28 14 14 14 28 14 26 14


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3.2. Definition

The firststep stepinin TRIZ methodology requires answering what the problems, what The first thethe TRIZ methodology requires answering what are theare problems, what benefits benefits are we to looking to achieve, are the functions and attributes contained in thesystem?. current are we looking achieve, and whatand arewhat the functions and attributes contained in the current system?. In this study, one useful TRIZ tool, function and attribute analysis (FAA), was employed to In this study, one useful TRIZ tool, function and attribute analysis (FAA), was employed to analyze and analyze and specify the problems that occurred in the assembly section. The evolution of the system specify the problems that occurred in the assembly section. The evolution of the system will be guided will beremoval guided by the harmful removalrelationships of the harmful relationships in improvement the system, and the by the of the in the system, and of improvement the insufficientofones. insufficient ones. This kind of function and attribute analysis model is helpful in managing the This kind of function and attribute analysis model is helpful in managing the complexity surrounding complexity surrounding system design and system. the improvement of thatthe system. Firstly,present; identifythen the system design and the improvement of that Firstly, identify components components present; then define the positive functional relationships; harmful,relationships; insufficient, define the positive functional relationships; define harmful, insufficient,define and excessive and relationships; and consider the time-variant issues. According to thethe function attribute and excessive consider the time-variant issues. According to the function attribute analysis, situation of the analysis, situation of assembly assemblythe is illustrated inthe Figure 12. is illustrated in Figure 12.

Figure Figure 12. 12. The The FAA FAA model to define the problem.

In Figure 12, 12,straight straightlines linesdenote denote “useful,” wavy lines indicate “harmful,” and dashed lines In Figure “useful,” wavy lines indicate “harmful,” and dashed lines show show “insufficient.” Therefore, two factors were defined in this paper. The first problem that “insufficient.” Therefore, two factors were defined in this paper. The first problem that occurred in occurred in the assembly section was that the quantities of frames and boards are not the same. the assembly section was that the quantities of frames and boards are not the same. There are more There boards thanitframes; therefore it is the necessary to replace the boardtype when making boardsare thanmore frames; therefore is necessary to replace board when making another of product. another type of product. The quantity of frames depends on the assembly area and cannot be The quantity of frames depends on the assembly area and cannot be changed. The quantity of boards changed. quantity boards Therefore, optimizes the the main costs question and benefits. Therefore, the main optimizesThe the costs and of benefits. behind this problem is thequestion optimal behind this problem is the optimal quantity of boards—“is it possible to make boards can be quantity of boards—“is it possible to make boards that can be used to make all types ofthat products? used to make all types of products? How can we make them?” The second problem is technical skills How can we make them?” The second problem is technical skills for how to change boards properly. for how to changelines, boards properly. manufacturing lines, screws andtoaremove drillingand machine used In manufacturing screws and aIn drilling machine are used as tools set upare a board as tools to remove and set up a board on a frame, as shown in Figure 11. However, it is a manual skill on a frame, as shown in Figure 11. However, it is a manual skill and takes about 15 min. Therefore, the and takes about 15 min. Therefore, the question emerges: “Is there a faster method for attaching question emerges: “Is there a faster method for attaching boards into the frame without using screws boards into the frame without using screws and drilling machines?” and drilling machines?” 3.3. 3.3. Select Select Tool Tool Select second step step of of the the TRIZ TRIZ process. process. It It determines determines the most appropriate appropriate problem problem Select tool tool is is the the second the most solving solving techniques techniques for for the the particular particular problem. problem. The The contradiction contradiction tools tools are are aa very very important important part part of of TRIZ, which was outperformed by 39 engineering parameters and the suggestion of 40 inventive TRIZ, which was outperformed by 39 engineering parameters and the suggestion of 40 inventive principles listed in in this this matrix. matrix. When When two twodifferent differentengineering engineeringparameters parametersconflict conflictwith witheach eachother, other, principles listed it it means thatthe thesystem systemhas hastechnical technicalcontradictions; contradictions;TRIZ TRIZresolves resolvesthe thecontradictions contradictions in in the the process, process, means that as Figure 13. 13. If engineering parameters become as shown shown in in Figure If one one of of the the engineering parameters improves, improves, the the other other one one will will become worse. Therefore the system needs to be better from the suggestion of the inventive principles in the contradiction matrix. As all of the 39 engineering parameters from TRIZ are investigated for this original problem of changing the board, what needs to be improved in the system are three


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worse. Therefore the system needs to be better from the suggestion of the inventive principles in the contradiction matrix. As all of the 39 engineering parameters from TRIZ are investigated for Sustainability 2016, 8, 420 14 of 19 this original problem of changing the board, what needs to be improved in the system are three parameters: moving object”; #26—“quantity of substance/the matter”; and parameters: #15—“duration #15—“durationofofaction actionofof moving object”; #26—“quantity of substance/the matter”; #35—“adaptability or versatility.” Those parameters that will get worse for the system are #1—“weight and #35—“adaptability or versatility.” Those parameters that will get worse for the system are of moving object” and #36—“device contradiction can be summarized as #1—“weight of moving object” and complexity.” #36—“deviceThe complexity.” Thematrix contradiction matrix can be shown in Table 5. summarized as shown in Table 5.

Figure 13. 13. Flow Flow chart chart of of problem problem solving Figure solving by by contradiction. contradiction. Table 5. Table 5. Contradiction Contradiction matrix matrix of of assembly assembly board. board.

Worsening Feature 1. Weight of Worsening Feature 1. Weight of Moving Object Improving Feature Improving Feature Moving Object 15.ofDuration of action of moving object 15. Duration action of moving object 26. Quantity substance/the matter 26.ofQuantity of substance/the matter 35. Adaptability or versatility or versatility 35. Adaptability

19,34,5,31 34, 31 19, 5, 35, 6, 35,18,6,31 18, 31 1, 6,1, 15,6,815, 8

36. Device 36. Device Complexity Complexity 10, 4, 29, 10, 15 4, 29, 15 3, 13, 3, 13, 27, 1027, 10 15, 29, 15, 37,29, 2837, 28

All of the inventive principles in this matrix are considered and discussed carefully according to the realistic conditions for Sumi-Hanel. We found that the most useful and feasible principles among due to to advanced advanced features. features. them are #5 and #13, which are recommended due #5. Merging, meaning:

• ‚ • ‚

Physically join or merge identical or related objects, operations, or functions. Physically join or merge identical or related objects, operations, or functions. Join or merge objects, operations, or functions so that they act together in time. Join or merge objects, operations, or functions so that they act together in time. #13. The other way round pointed out ideas that: #13. The other way round pointed out ideas that: • Use an opposite action(s) to solve the problem (e.g., instead of cooling an object, heat it). •‚ Make fixed, and fixed objects movable. Use anmovable oppositeobjects action(s) to solve the problem (e.g., instead of cooling an object, heat it). Turn the object,objects system, or process “upside down”. ‚• Make movable fixed, and fixed objects movable. ‚ Turn thepaper, object,the system, or process “upside down”. concepts can serve as a design direction to In this selected principles or solution improve and redesign the original product with innovative ideas. If any parameter of the contradiction matrix cannot be clearly identified after the problem formulations, it means it produces negative results. This paper suggests reselecting the best tool from the 40 principles and using it to find the most desired solution by applying the TRIZ problem solving tool.


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In this paper, the selected principles or solution concepts can serve as a design direction to improve and redesign the original product with innovative ideas. If any parameter of the contradiction matrix cannot be clearly identified after the problem formulations, it means it produces negative results. This paper suggests reselecting the best tool from the 40 principles and using it to find the Sustainability 2016, 8, 420 by applying the TRIZ problem solving tool. 15 of 19 most desired solution Sustainability 2016, 8, 420 15 of 19

3.4. 3.4. Generate Generate the the Solution Solution Generate the solution third of the methodology and the stage where many thethe third stepstep of the methodology and the stage Generate the thesolution solutionisis is the third step of TRIZ the TRIZ TRIZ methodology and thewhere stage many whereoptions many options are generated by using TRIZ tools. In this paper, inventive principle #5 (Merging) are generated by using TRIZ tools. TRIZ In thistools. paper,Ininventive principle #5 (Merging) the options are generated by using this paper, inventive principleenumerates #5 (Merging) enumerates the differences between board type 1 and board type 2. There are some differences in differences between board type 1 and board type 2. There are some differences in the distribution of enumerates the differences between board type 1 and board type 2. There are some differences in the the distribution of the branches, as shown in Figure 14. the branches, as shown in Figure 14. distribution of the branches, as shown in Figure 14.

Figure 14. The diagram of assembly board types 1 and 2. Figure 14. The diagram of assembly board types 1 and 2.

One frame can only support board. However, inventive principle #13 (“the other way framecan canonly only support one board. However, inventive principle #13other (“theway other way One frame support oneone board. However, inventive principle #13 (“the round”) round”) gives a good suggestion: “turn the object, system, or process upside down.” This means round”) givessuggestion: a good suggestion: object,orsystem, process upside down.” one gives a good “turn the “turn object,the system, processorupside down.” This meansThis onemeans frame one can frame can support two boards, and the boards can be rotated in order to be reserved when changing frame can support two and the can in beorder rotated to be reserved whenthe changing support two boards, andboards, the boards canboards be rotated to in be order reserved when changing type of the product. Figure the board and rotating the type type of of product. Figure 15 15 presents the single single board and the the rotating board. board. product. Figure 15 presents thepresents single board and the rotating board.

Figure 15. The single board and the rotating board. Figure 15. The single board and the rotating board.

The The quantity quantity of of rotating rotating frame frame (X) (X) that that can can bring bring two two frames frames depends depends on on the the total total quantity quantity of of The quantity of rotating frame (X) that can bring two frames depends on the total quantity of boards (Y) and the quantity of frames (Z). boards (Y) and the quantity of frames (Z). boards (Y) and thenot quantity of frames (Z). If If Y Y == Z, Z, it it is is not necessary necessary to to use use aa rotating rotating frame. frame. One One frame frame supports supports one one board. board. If Y = Z, it is not necessary to use a rotating frame. One frame supports one board. by using the If Y > Z, the rotating frame is used. The quantity of rotating frames is calculated If Y > Z, the rotating frame is used. The quantity of rotating frames is calculated by using the If Y > =Z,Ythe rotating frame is used. The quantity of rotating frames is calculated by using the formula formula X X = Y −− Z. Z. formula X = Y ´then Z. If If Y Y == 22 ×× Z Z then X X == 22 ×× Z Z −− Z Z == Z, Z, all all the the frames frames in in the the conveyor conveyor are are rotating rotating ones. ones. If Y = 2 ˆ Z then X = 2 ˆ Z ´ Z = Z, all the frames in the conveyor are rotating ones. If If Y Y >> 22 ×× Z Z then then all all the the frames frames in in the the conveyor conveyor are are rotating rotating ones, ones, but but it it is is required required to to change change If Y > 2 ˆ Z then all the frames in the conveyor are rotating ones, but it is required to change boards using the old method. Table 4 indicates that Max(Y) = 2 × Z, or this situation has boards using the old method. Table 4 indicates that Max(Y) = 2 × Z, or this situation has never never boards using the olditmethod. Table 4 indicates that Max(Y) = 2 ˆ Z, or this situation has never appeared. Therefore, is not under consideration anymore. appeared. Therefore, it is not under consideration anymore. appeared. Therefore, the it is not under consideration is anymore. In In this this research, research, the Wagon Wagon engine engine conveyor conveyor is taken taken as as an an example: example: The total quantity of boards is Y = 27. The total quantity of boards is Y = 27. The The total total quantity quantity of of frames frames is is Z Z == 20. 20. The quantity of rotating frames The quantity of rotating frames is is X X == Y Y −− Z Z == 27 27 −− 20 20 == 77 frames. frames. This means seven rotating frames are needed to solve This means seven rotating frames are needed to solve the the problem. problem. The The layout layout of of boards boards is is shown shown in in Figure Figure 16. 16.


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In this research, the Wagon engine conveyor is taken as an example: The total quantity of boards is Y = 27. The total quantity of frames is Z = 20. The quantity of rotating frames is X = Y ´ Z = 27 ´ 20 = 7 frames. This means seven rotating frames are needed to solve the problem. The layout of boards is shown Sustainability 2016, 8, 420 16 of 19 in Figure 16.

Figure Figure16. 16.The Thenew newlayout layoutofofassembly assemblyboards boardsininthe theconveyor. conveyor.

3.5. 3.5.Evaluation Evaluation The Thefinal finalpart partof of the the systematic systematiccreativity creativityprocess processisis the the one one associated associatedwith with evaluating evaluatingthe the solutions solutionsobtained obtainedduring duringprevious previousstages. stages.InInthis thispaper, paper,the theproblems problemsofofassembly assemblyboards boardsare aresolved solved successfully successfullyby byapplying applyingTRIZ TRIZmethodology. methodology.This Thishelps helpsa acompany companytotosave savespace, space,time, time,and andmoney. money. The time for a board change is reduced by 10 min compared to the original time, which helps The time for a board change is reduced by 10 min compared to the original time, which helpstoto speed operation and andproductivity. productivity.This Thisreduces reduces time spent changing boards by speedup up conveyor conveyor operation thethe time spent changing boards by 67%. 67%. Therefore, working overtime is not required and companies can save manpower and costs. Therefore, working overtime is not required and companies can save manpower and costs. Moreover, a Moreover, a waiting area is not necessary anymore, all the boards are carried by waiting area for boards is for notboards necessary anymore, because all thebecause boards are carried by rotating frames. rotating frames. space saved byconveyor eliminating onesquare conveyor is 8400 square meters, which was The space savedThe by eliminating one is 8400 meters, which was used to store waiting used to store waiting boards. This is a significant improvement. Instead, these areas can be used boards. This is a significant improvement. Instead, these areas can be used to set up a new conveyortoor set up a capacity. new conveyor capacity. thenew costconveyors saved from new increase Finally, or theincrease cost saved from notFinally, setting up is atnot leastsetting $24,000up (around conveyors is at the least $24,000 (around theofcompany drive down theThe costs of of labor 20%), because company can drive20%), downbecause the costs labor andcan waste production. aim this and waste production. The aim of this study has been achieved and it can be evaluated as the best study has been achieved and it can be evaluated as the best solution for improving manufacturing solution for improving manufacturing lines according both6 gives quantitative and of qualitative lines according to both quantitative and qualitative standards.toTable a comparison this study standards. Table 6 gives a comparison of this study before and after improvements. before and after improvements. Table Table6.6.Comparison Comparisonofofthe theresearch researchresults resultsbefore beforeand andafter afterimprovement. improvement. Items Items Free area for the new conveyors Free area for the new conveyors Time of changing board Time of changing board Cost of setting up new conveyors Cost of setting up new conveyors

Before 1400 m2 2 1400 15mmin 15 min $120,000 $120,000 Before

After 9800 m2 2 98005m min 5 min $96,000 $96,000 After

Evaluation Saved 8400 m2 Saved 8400by m210 min Reduced Reduced by 10 min Saved $24,000 Saved $24,000 Evaluation

Improvement 600% 600% 67% 67% 20% 20%

Improvement

4. Conclusions 4. Conclusions In the 1990s the automobile industry fell on hard times because of the Japanese asset price In the 1990s the automobile industry fell on hard times because of the Japanese asset price bubble bubble and extreme currency appreciation. During the 2000s and up to the global economic crisis of and extreme currency appreciation. During the 2000s and up to the global economic crisis of 2008, 2008, most companies coped with the challenges. This paper proposes an innovative approach, most companies coped with the challenges. This paper proposes an innovative approach, combining combining TRIZ with lean manufacturing concepts, which can lead to continuous improvement in TRIZ with lean manufacturing concepts, which can lead to continuous improvement in manufacturing manufacturing lines and enhance sustainable development for companies. Besides that, it gives lines and enhance sustainable development for companies. Besides that, it gives insights in terms insights in terms of understanding the overview impact of a global economic recession and its specific consequences in Japan as is the automobile industry is key to the nation’s economy. TRIZ, combined with lean manufacturing, was adopted by the authors and was found to outperform the traditional approaches. By correctly defining the problem, the solution to the problem can be found quickly. Define, select tool, generate solutions, and evaluate are the four major steps related to the systematic creativity and form a loop. When a problem is defined differently, different solutions and


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of understanding the overview impact of a global economic recession and its specific consequences in Japan as is the automobile industry is key to the nation’s economy. TRIZ, combined with lean manufacturing, was adopted by the authors and was found to outperform the traditional approaches. By correctly defining the problem, the solution to the problem can be found quickly. Define, select tool, generate solutions, and evaluate are the four major steps related to the systematic creativity and form a loop. When a problem is defined differently, different solutions and effects can be obtained. Therefore, this study suggests going through the steps more than once in order to obtain a better solution. The power of TRIZ, with its analytical tools, is that it can be employed to identify the problems of an assembly board, while TRIZ technical tools can help to generate better ideals by using a contraction matrix and inventive principles. Furthermore, according to empirical analysis, the problems occurring at the replacing assembly board section undergo a big improvement when we apply the TRIZ approach. This research has contributed a new approach to solving the problem of supplier Sumi-Hanel. The study results successfully eliminate the wasted time spent changing a board, decreasing the original time schedule by 10 min. Moreover, the more than 8000 square meters used as a waiting area for the assembly boards and old layout conveyor can also be saved. This gives the firm more space for setting up new conveyors and it runs more efficiently due to this technological enhancement. Therefore, the operators do not have to work overtime at weekends. The objective of this study has been successfully achieved. As to the limitations of this research, the researchers would like to contribute to an overview of the Japanese automobile industry and accordingly implemented the integrated methodologies of lean manufacturing and TRIZ to give meaningful and helpful ideas about sustainable manufacturing for other companies in a variety of industries. However, two limiting factors were found in the empirical results: the quantity of boards (Y) and frames (Z). By using a rotating board, these problems were solved completely in this paper. However, in the future, if the conveyors use more types of board (Max (Y) > 2 ˆ Z), then other papers should suggest different parameters and inventive principles in order to generate better solutions. This situation needs more time to analyze and it can be the topic for another study. For further study we also suggest investigating problems in other sections such as material coordination, cutting and crimping, etc. More methodologies can be applied to continuously improve the productivity in further studies. Author Contributions: Chia-Nan Wang and Ying-Fang Huang designed the research and provided ideas; Thi-Nham Le analyzed the data and wrote the manuscript. Thanh-Tuan Nguyen collected data from Sumi-Hanel auto parts supplier and was involved in the results discussion. All authors have read and approved the final manuscript. Conflicts of Interest: The authors declare no conflict of interest.

Abbreviations The following abbreviations are used in this manuscript: TRIZ FAA OEM PVC

Teoriya Resheniya Izobreatatelskih Zadatch function and attribute analysis original equipment manufacturer polyvinyl chloride

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