1. Class 6_1 Today’s topic: More on engineering analysis and modeling Your “computer modeling” assignment

2. DP questions?

3. Monitors off, please

4. Define the problem Specify product requirements Invent alternatives Evaluate the alternatives Engineer the details / analyze performance Test prototypes Report complete product description Model of the Design Process

5. Engineer the details Where most design time spent Requires technical knowledge

6. Engineering analysis has several characteristics It is quantitative (math, numbers, units) It uses science & engineering theories, engineering experience, test data It is always recognized as an approximation to reality It typically breaks a complicated problem into smaller pieces It delivers an answer within the limitations of time, money, and knowledge available.

7. All engineering analyses are Models

8. What is a model? A purposeful representation of some part of the real world. Real system Model Computer Modeling Simulation

9. Why build models? To predict how a system will behave. To help test our understanding of a system.

10. Computers are powerful modeling tools Caution: the model is still only as good as the understanding that goes into making it! GIGO (garbage in…garbage out)

11. Why? Analysis is difficult. Analysis is uncertain. Why go to the trouble?

12. Why do analysis? Because it make engineered solutions possible! Without analysis as part of the design process we are just tinkerers. The ability to make analytical models of the physical world is what distinguishes engineers.

13. Your assignment Build an analytical model to predict the performance of your design. Your work will be part of your final design report. It is a major part of the grade. It should be done now, at this stage of the design process…don’t procrastinate!

14. What it should be when done: 1.Defines the purpose by posing questions to be answered 2.Derives the analysis from first principles 3.Implements the analysis using a MatLab program 4.Provides information that is useful in designing the details of your device

15. Let’s quickly look a some other examples Check the “computer model” page of our class web site.

16. Check out the “computer modeling” pages on our website

17. Planning session Start planning your analysis. Begin by defining the purpose of the model by developing a list of questions you would like your analysis to answer. Start making that list now.

18. Please start doing your analysis Start now Study examples on class web page Next we will review MatLab programming (You do not need this to start your analysis) Come see me if you need help

19. Have a good break!