Design Process. Design process is the organization and management of people and the information they develop in the evolution of the product.

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1 Design Process What is the design process? Design process is the organization and management of people and the information they develop in the evolution of the product. Why study the design process? Design process determines the efficiency of new product development. 85% of the problems with new products not working as intended, taking too long to bring to market, or costing too much are the result of poor design process. The design process needs to improved consistently and executed for developing better products because: There is a continuous need for new, cost-effective, high-quality products. Most products require a team of people from diverse areas of expertise to develop an idea into hardware. We will study the design process to get the tools to develop an efficient design process regardless of the product being developed. 3 types of knowledge used by designers: Knowledge to generate ideas Experience and natural ability Knowledge to evaluate ideas Experience and formal training (focus of most engineering education) Knowledge to structure the process Non-domain-specific knowledge What we will study in this class

2 Importance of the Design Process 3 Measures of the effectiveness of the design process: Product Cost Quality Time to market Manufacturing cost is significantly influenced by the design quality although the design cost is only a small portion of the total cost (Figures 1 and 2). Actual cost of design is usually a small portion of the manufacturing cost. 5 % of the manufacturing cost in Ford Motor The effect of the quality of the design on the manufacturing cost is much greater. Xerox attributes 50% of the final cost to the results of the design process. The decisions made during the design process have a great effect on the cost of a product but cost very little. Product quality cannot be manufactured into a product unless it is designed into it. (Table 1.1) Function: works as it should, incorporates latest technology, last long Form designed Materials Manufacturing process: reduced line-fallout, easier and faster assembly etc. Effect on the time to produce a new product (Figures 1.6): Design Axiom: Fail early, fail often Changes are required in order to find a good design, and early changes are easier and less expensive than changes made later.

3 History of the Design Process One person, with sufficient knowledge of the physics, materials and manufacturing processes to manage all aspects of the design and construction of the project, could design and manufacture an entire product in the past. By the middle of the 20 th century, products and manufacturing processes had become too complex for one person to have sufficient knowledge or time to focus on all aspects of the evolving product. Different groups of people for marketing, design, manufacturing and overall management One-way communication over the wall: What is manufactured is not often what the customer had in mind. Inefficient, costly, and greater possibility for making poor-quality products

4 Simultaneous Engineering (in late 1970s and early 1980s): Simultaneous development of the manufacturing process with the evolution of the product by assigning manufacturing representatives to be members of design team Concurrent Engineering (in late 1980s): History of the Design Process Integrated Product and Process Design (IPPD) in the 1990s A greater refinement in thought about what it takes to efficiently develop a product Primarily focusing on the integration of teams of people, design tools and techniques, and information about the product and the processes used to develop and manufacture it. 10 Key Features of Concurrent Engineering Focus on the entire product life (chap 1) Use and support of design team (chaps 3 and 5) Realization that the processes are as important as the product (chaps 4 and 5) Attention to planning for information-centered tasks (chap 5) Careful product requirements development (chap 6) Encouragement of multiple concept generation and evaluation (chaps 7 and 8) Awareness of the decision-making process (chap 8) Attention to designing in quality during every phase of the design process (throughout) Concurrent development of product and manufacturing process (chaps 9-13) Emphasis on communication of the right information to the right people at the right time (throughout) A key point of concurrent engineering is a concern for information. Drawings, plans, concept sketches, meeting notes, etc.

5 The Life of A Product *Process of idea development, production, use, and end of product life. *The whole whole process must be considered in the design process.

6 Controllable Variables in Concurrent Engineering

7 Basic Elements in Product Design

8 Design Problems What size SAE grade 5 bolt should be used to fasten together two pieces of 1045 sheet steel (4 mm thick and 6 cm wide) which are lapped over each other and loaded with 100 N? Design a joint to fasten together two pieces of 1045 sheet steel (4 mm thick and 6 cm wide), which are lapped over each other and loaded with 100 N? - Well defined analysis problem finding the diameter of the bolt HWK#1: Ill-defined design problem with number of potential problems - How to connect the sheets? (Bolted, glued, welded, etc.?) - Disassembly required later? - What working environment? - etc. Change a problem from one of your engineering science classes into a design problem by changing as few words as possible. Do your home work in your design notebook. Due is one week.

9 Design problems have many satisfactory solutions and no clear best solution. Design problems - are ill-defined; - have no correct answer; - have no clear best answer. Design process knowledge is based upon the domain knowledge. Mechanical design problems begin with an ill-defined need and result in a piece of machinery that behaves in a certain way. PARADOX: A designer must develop a machine that has the capabilities to meet some need that is not fully defined.