3-1 CHAPTER 3 Introduction to Engineering Design © 2011 Cengage Learning Engineering. All Rights Reserved.

3-2 Outline In this chapter we will Introduce you to the engineering design process Discuss the basic steps that most engineers follow when designing a product Discuss the importance of considering sustainability in design © 2011 Cengage Learning Engineering. All Rights Reserved.

3-3 Outline Introduce important design factors such as  Teamwork  Project scheduling  Material selection  Economic consideration  Engineering standards and codes Present cases studies in civil, mechanical/ electrical engineering © 2011 Cengage Learning Engineering. All Rights Reserved.

3-4 Objectives The main objective of this chapter is: To introduce the steps engineers follow to successfully design products or provide services that we use in our everyday lives © 2011 Cengage Learning Engineering. All Rights Reserved.

The Engineering Design Process Keywords: “Engineering Design Process”

3-6 Design Process – Basic Steps 1.Recognizing the need for a product or a service 2.Problem definition and understanding 3.Research and preparation 4.Conceptualization 5.Synthesis 6.Evaluation 7.Optimization 8.Presentation © 2011 Cengage Learning Engineering. All Rights Reserved.

3-7 Design Process – Basic Steps Step 1: Recognizing the need for a product or a service © 2011 Cengage Learning Engineering. All Rights Reserved.

3-8 Design Process – Basic Steps Step 2: Problem definition and understanding This is the most important step in any design process Before you move on to the next step  Make sure you understand the problem  Make sure that the problem is well defined Good problem solvers are those who first fully understand what the problem is © 2011 Cengage Learning Engineering. All Rights Reserved.

3-9 Design Process – Basic Steps Step 3: Research and preparation Collect useful information  Search to determine if a product already exists  Perhaps you could adopt or modify existing components  Review and organize the information collected in a suitable manner Step 4: Conceptualization (aka. Brainstorming) Generate ideas or concepts that could offer reasonable solutions to your problem © 2011 Cengage Learning Engineering. All Rights Reserved.

3-10 Design Process – Basic Steps Step 5: Synthesis At this point you begin to consider details Perform calculations, run computer models, narrow down the type of materials to be used, size the components of the system, and answer questions about how the product is going to be fabricated Consult pertinent codes and standards for compliance © 2011 Cengage Learning Engineering. All Rights Reserved.

3-11 Design Process – Basic Steps Step 6: Evaluation Analyze the problem in more detail Identify critical design parameters and consider their influence in your final design Make sure that all calculations are performed correctly Best solution must be identified from alternatives Details of design must be worked out fully © 2011 Cengage Learning Engineering. All Rights Reserved.

3-12 Design Process – Basic Steps Step 7: Optimization – minimization or maximization Optimization is based on some particular criterion such as cost, strength, size, weight, reliability, noise, or performance. Optimizing individual components of an engineering system does not necessarily lead to an optimized system © 2011 Cengage Learning Engineering. All Rights Reserved.

3-13 Design Process – Basic Steps An optimization procedure © 2011 Cengage Learning Engineering. All Rights Reserved.

3-14 Design Process – Basic Steps Step 8: Presentation You need to communicate your solution to the client, who may be your boss, another group within your company, or an outside customer Engineers are required to give oral and (written) progress reports on a regular basis to various groups; consequently, presentation could well be an integral part of many other design steps © 2011 Cengage Learning Engineering. All Rights Reserved.

3-15 Other Engineering Design Considerations Engineering economics Material selection Teamwork Conflicts Resolution Project scheduling and task chart Evaluating alternatives Patent, trademark, and copyright Engineering standards and codes © 2011 Cengage Learning Engineering. All Rights Reserved.

3-16 Engineering Economics Economic factors always play important roles in engineering design decision making Products that are too expensive cannot be sold at a price that consumers can afford and still be profitable to the company Products must be designed to provide services not only to make our lives better but also to make profits for the manufacturer More in Chapter 20 © 2011 Cengage Learning Engineering. All Rights Reserved.

3-17 Material Selection Selection of materials is an important design decision Examples of properties to consider when selecting materials  Density  Ultimate strength  Flexibility  Machinability  Durability  Thermal expansion  Electrical & thermal conductivity  Resistance to corrosion © 2011 Cengage Learning Engineering. All Rights Reserved.

3-18 Material Properties Material properties depend on many factors  How the material was processed  Its age  Its exact chemical composition  Any nonhomogenity or defect within the material Material properties change with temperature and time as the material ages In practice, you use property values provided by the manufacturer for design; textbook values are typical values © 2011 Cengage Learning Engineering. All Rights Reserved.

3-19 Material Properties Electrical resistivity Density Modulus of Elasticity Modulus of Rigidity Tensile strength Comprehensive strength Modulus of resilience Modulus of toughness Strength-to-Weight ratio © 2011 Cengage Learning Engineering. All Rights Reserved. Thermal expansion Thermal conductivity Heat capacity Viscosity Vapor pressure Bulk modulus of compressibility

3-20 Teamwork Design team a group of individuals with complementary expertise, problem solving skills, and talent who are working together to solve a problem or achieve a common goal Employers are looking for individuals who not only have a good grasp of engineering fundamentals but who can also work well with others in a team environment © 2011 Cengage Learning Engineering. All Rights Reserved.

3-21 Common Traits of Good Teams Successful teams have the following components: The project that is assigned to a team must have clear and realistic goals. These goals must be understood and accepted by all members of the team. The team should be made up of individuals with complementary expertise, problem solving skills, background, and talent. The team must have a good leader. © 2011 Cengage Learning Engineering. All Rights Reserved.

3-22 Common Traits of Good Teams The team leadership and the environment in which discussions take place should promote openness, respect, and honesty. The team goals and needs should come before individual goals and needs. © 2011 Cengage Learning Engineering. All Rights Reserved.

3-23 Secondary Roles of Good Team Members The Organizer – experienced and confident; trusted by members of the team and serves as a coordinator for the entire project The Creator – good at coming up with new ideas, sharing them with other team members, and letting the team develop the ideas further The Gatherer – enthusiastic and good at obtaining things, looking for possibilities, and developing contacts © 2011 Cengage Learning Engineering. All Rights Reserved.

3-24 Secondary Roles of Good Team Members The Motivator – energetic, confident, and outgoing; good at finding ways around obstacles The Evaluator – intelligent and capable of understanding the complete scope of the project; good at judging outcomes correctly The Team Worker – tries to get everyone to come together, does not like friction or problems among team members © 2011 Cengage Learning Engineering. All Rights Reserved.

3-25 Secondary Role of Good Team Members The Solver – reliable and decisive and can turn concepts into practical solution The Finisher – can be counted on to finish his or her assigned task on time; detail oriented and may worry about the team’s progress toward finishing the assignment © 2011 Cengage Learning Engineering. All Rights Reserved.

3-26 Conflicts When a group of people work together, conflicts sometimes arise. Conflicts could be the result of Miscommunication Personality differences The way events and actions are interpreted by a member of a team © 2011 Cengage Learning Engineering. All Rights Reserved.

3-27 Conflict Resolution Managing conflicts is an important part of a team dynamic In managing conflicts, it is important to recognize there are three types of people:  Accommodating  Compromising  Collaborative © 2011 Cengage Learning Engineering. All Rights Reserved.

3-28 Conflict Resolution – Type of People Accommodating team members - avoid conflicts  Allow assertive individuals to dominate  Making progress as a whole difficult  Could lead to poor team decision © 2011 Cengage Learning Engineering. All Rights Reserved.

3-29 Conflict Resolution – Type of People Compromising team members Demonstrate moderate level of assertiveness and cooperation. By compromising, the team may have sacrificed the best solution for the sake of group unity © 2011 Cengage Learning Engineering. All Rights Reserved.

3-30 Collaborative Conflict Resolution Approach  High level of assertiveness and cooperation by the team  No finger pointing  Team proposes solutions  Means of evaluation  Combine solutions to reach an ideal solution Conflict Resolution © 2011 Cengage Learning Engineering. All Rights Reserved.

3-31 Project Scheduling and Task Chart A process that engineering managers use to ensure that a project is completed on time and within the allocated budget © 2011 Cengage Learning Engineering. All Rights Reserved.

3-32 Evaluating Alternatives When a design is narrowed down to a few workable concepts, evaluation of these concepts is needed before detail design is pursued Each design would have its own evaluation criteria An Example of evaluation worksheet © 2011 Cengage Learning Engineering. All Rights Reserved.

3-33 Sustainability in Design Sustainability and sustainable engineering can be defined as “design and development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” © 2011 Cengage Learning Engineering. All Rights Reserved.

3-34 Sustainability in Design Engineers contribute to both private and public sectors of our society In private sector, they design and produce the goods and services that we use in our daily lives to allow us to enjoy a high standard of living In public sector, they support local, state, and federal mission such as meeting our infrastructure needs, energy and food security, and national defense © 2011 Cengage Learning Engineering. All Rights Reserved.

3-35 Sustainability in Design Increasingly, because of worldwide socioeconomic trends, environmental concerns, and earth’s finite resources, more is expected of engineers Future engineers are expected to design and provide goods and services that increase the standard of living and advance health care, while addressing serious environmental and sustainability concerns In designing products and services, engineers must consider the link among earth’s finite resources, environmental, social, ethical, technical, and economical factors © 2011 Cengage Learning Engineering. All Rights Reserved.

3-36 Summary You should know the basic design steps that all engineers follow, regardless of their background, to design products and services You should realize that economics plays an important role in engineering decision making You should realize that the selection of material is an important design decision You should be familiar with the common traits of good teams © 2011 Cengage Learning Engineering. All Rights Reserved.

Questions? Engineering Design