Presentation is loading. Please wait.

Presentation is loading. Please wait.

ENGR 107: Engineering Fundamentals Lecture 7: The Engineering Design Process: Making Design Decisions Using Tradeoff Analyses C. Schaefer September 29,

Similar presentations


Presentation on theme: "ENGR 107: Engineering Fundamentals Lecture 7: The Engineering Design Process: Making Design Decisions Using Tradeoff Analyses C. Schaefer September 29,"— Presentation transcript:

1 ENGR 107: Engineering Fundamentals Lecture 7: The Engineering Design Process: Making Design Decisions Using Tradeoff Analyses C. Schaefer September 29, 2003

2 Egnineering Fundamentals 1072 Stuff Review Project 1 Yacht design handouts Yacht diagram: – http://www.cnn.com/interactive/sailing/yacht.diagram/ http://www.cnn.com/interactive/sailing/yacht.diagram/ Lecture

3 September 29, 2003Egnineering Fundamentals 1073 Project 2 Begins!! For each Team, all functional groups shall provide cost ROM’s, Bills of Material, and a list of required tools to the Systems Engineering Group and to me by next Monday. Systems Engineering group: preliminary schedule and budget due next Wednesday. Design and Manufacturing Groups: begin conceptual and preliminary design of your respective systems. Handout $$ and radios on Wednesday.

4 September 29, 2003Egnineering Fundamentals 1074 Engineering Decisions Engineering decision – selecting a specific solution to a design problem from a set of alternative solutions Trade-off analysis – an analysis technique in which the performance of various design alternatives are evaluated by varying different design parameters within a design space defined by parameter boundaries or design constraints. Payoff function – a mathematical model that relates system performance to various design parameters that the designer can control.

5 September 29, 2003Egnineering Fundamentals 1075 Analyze Potential Solutions Narrow the ideas generated during the brainstorming phase to several realistic alternatives. Analytical techniques to narrow choice: – Estimation (“back of the envelope” calculations). – Common sense. – Economic analysis. – Engineering analysis. – Computer analysis.

6 September 29, 2003Egnineering Fundamentals 1076 Using Models in the Decision Making Process Mathematical models. Computer models. – CAD (computer aided design) – Simulink Scale models. – Wind tunnel models – Mockups Diagrams or graphs. – Free body diagrams Math models often implemented as computer models.

7 September 29, 2003Egnineering Fundamentals 1077 Model Features Should represent the dynamics of the system being represented. Good fidelity: simple to understand and manipulate but good enough to generate believable results. Should address the most important design parameters. Ignore higher order terms. Should be repeatable. Should be of modest complexity: complexity often a function of time and budget constraints on design process. Easily modified.

8 September 29, 2003Egnineering Fundamentals 1078 Mathematical Models Uncovers relations between the various aspects of the problem that may not be apparent in verbal descriptions. Enables comparisons of many possible solutions. Illustrates cause-and-effect relationships. Defines the type of data required to solve the problem. Can be used for prediction and forecasting. Aids in identifying areas of risk and uncertainty.

9 September 29, 2003Egnineering Fundamentals 1079 Mathematical Model Example: Yacht Rating Measurement Formula

10 September 29, 2003Egnineering Fundamentals 10710 Payoff Function: Length = f (Sail Area, Displacement)

11 September 29, 2003Egnineering Fundamentals 10711 Excel Spreadsheet Solution

12 September 29, 2003Egnineering Fundamentals 10712 Parametric Analysis

13 September 29, 2003Egnineering Fundamentals 10713 Parametric Analysis

14 September 29, 2003Egnineering Fundamentals 10714 Parametric Analysis

15 September 29, 2003Egnineering Fundamentals 10715 Payoff Function: Sail Area = f (Length, Displacement)

16 September 29, 2003Egnineering Fundamentals 10716 Excel Spreadsheet Solution

17 September 29, 2003Egnineering Fundamentals 10717 Parametric Analysis

18 September 29, 2003Egnineering Fundamentals 10718 Payoff Function: Displacement = f (Sail Area, Length)

19 September 29, 2003Egnineering Fundamentals 10719 Excel Spreadsheet Solution

20 September 29, 2003Egnineering Fundamentals 10720 Parametric Analysis

21 September 29, 2003Egnineering Fundamentals 10721 How Important are the Criteria in the Decision Process? Working Criteria Points Avail.#1#2#3 Cost20101518 Prod. Difficulty 1581214 Size, Weight, Strength 5544 Appearance 10768 Convenience5344 Safety10878 Legal5444 Reliability157911 Recyclability5434 Appeal10789 TOTAL100637284


Download ppt "ENGR 107: Engineering Fundamentals Lecture 7: The Engineering Design Process: Making Design Decisions Using Tradeoff Analyses C. Schaefer September 29,"

Similar presentations


Ads by Google