Modular products can be made by combining standardized and customized components. This allows standard components to be inventoried, and then customization can be focused on the differentiating components.
Also, modular products can be a combination of standard components, that is, the same standard components (usually kept in inventory) are integrated in different ways to form a variety of products that can respond to customer requirements.
Design for Modularity
A three-phase methodology is proposed for the development of complex products using the modularity concept [39]. The proposed methodology matches the criteria set by the design for functionality, assembly, and manufacture. Figure 3.1 illustrates an overview of the product design sequence in the proposed methodology.
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Figure 3.1. Overview of the Proposed Design Environment
Some of the major benefits associated with this methodology include:
• Increased design accuracy and efficiency and the reuse of existing design for new programs.
• Potential for integration of the developed methodology and technology into the engineering design activities.
• Modular product design and the process of planning the production are integrated in one overall engineering process in which product features are mapped into their feasible process(es) in a one-to-one
correspondence.
The steps associated with this methodology include [39]:
Phase I-Decomposition Analysis: Design for Modularity and Classification
• Product and problem decomposition
• Structural and modular decomposition
• Associativity analysis between the components and specifications
• Application of group technology classification system
• Construction of the associativity measure matrix
• Optimum module selection
Phase ll-Product Analysis: Design for Assembly and Functionality Analysis
• Identify the components that could be produced and assembled separately
• Determine the order of disassembly and assembly for each sub- component module
• Establish the interfaces based on the analysis of the design features
• Determine the order in which the sub-assemblies are assembled to produce the final product
Phase llI-Process Analysis: Design for Manufacture
• Family identification and template retrieval
• Determination of the logical order of GT codes for the process of modules
• Machine and process parameter calculation
• Variant process planning
Phase I of this methodology (Figure 3.2) is the focus of this chapter.
Further specifications associated with this phase include:
• Needs analysis
• Requirements analysis
• Concept analysis
• Concept Integration
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Figure 3.2. Design for Modularity
1. NEEDSANALY~S
The design engineer is usually given an ill-defined problem. In many situations, the designer has to respond to the mere suggestion that there is a need for a product to perform a certain function. One of the main tasks is to find out precisely what the needs are and what customers really want. An important step in the design is to describe the product fully in terms of functional needs and physical limitations. These functional needs and physical limitations will form the product specifications.
Several sources of information can be used to identify the needs [56].
Such sources include potential customers, the company for which the design is being made, the competition, and any authorities that can impose restrictions on the product (standards, safety, etc.).
Information required to identify customer needs can be collected by surveying prospective purchasers or customers. This can be done by conducting a marketing study that begins by establishing target markets and customers . Then customers' wants and needs can be obtained by using several methods such as interviews and questionnaires. Also, similar products (competitive products) are investigated to find possible improvement opportunities by focusing on weakness points and features desired by customers.
Next, customer wants and needs are arranged into groups and prioritized according to their importance. Needs analysis usually results in a statement of recognized needs and the expected manner in which those needs should be met. The resulting infonnation is used to identifY the requirements.
Satisfying the customer needs is a critical task, since the customer is becoming the center of successful product development efforts, that is, organizations are trying to explore what the customer needs and to deploy these needs into their products. Furthermore, organizations are trying to exceed customer needs and expectations to the point that the customer is delighted. The focus on customer needs is stimulated by the high competition resulting from the globalization of organizations operating in a globalized market place. This makes understanding the customer needs and expectations a valuable tool to maintain current business and to compete effectively to gain new business.
Satisfying the customer is not an easy task. It involves the process of communicating with customers to understand what they really need and then to translate these needs into specifications that can be met by products or services provided by the organization. Next, customer reaction to these new products/services is collected and incorporated into the development effort to improve the products/services and thus increase customer satisfaction.
The process of satisfying the customer can be viewed as an ongoing process (Figure 3.3). The process should be performed continually as long the organization is in business.
Produce Products/Service
t
Collect Customer
• Needs/Expectations •
Figure 3.3. Customer Satisfaction Process
Translate Needs into Specifications
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Customer satisfaction is an important step toward gaining customer loyalty and ensuring stable and growing market share. It is important for organizations to realize that only highly satisfied customers are most likely to become loyal cLlstomers. Customer loyalty can be measured by the retention rate an organization has. Also, customer loyalty differs depending on how much the customer is satisfied. A "very satisfied" customer is more likely to repurchase a product than a "satisfied" customer [25]. The importance of satisfying customers can be substantiated by the difference in cost between maintaining existing customers and attracting new customers.
It costs about five times more to attract a new customer than to maintain a current customer [52].
It can be argued that market share is a direct result of both customer satisfaction and loyalty. An organization with highly satisfied customers, and thus loyal customers, will have higher retention rates and can gain more market share.