13(2 2 0):

: :(Objective) , , , , , . : , , , , .:1. 2. , 3. 4. 5. - - - -

1: , . . 2: , . .. ISO . . . 3: , 3-D . . 3-D , 4: , () . . . . 5: , . -. . . 6: , . . (, ..) . (, , , ..) . 7: , . . (, , ) . 8: , . . . . 9: , , , , , . . . . . 10: , . . . .:5%20%()3x25% = 75% Grade:0 - 40F41 - 50 D51 - 55D+56 - 65C66 - 70C+71 - 75B76 80B+80 100A

:( ) ,

? - .- .

? WHAT IS MECHANICAL DESIGN?: , , .: may be defined as any organized body of knowledge. : , , .WHAT IS MECHANICAL DESIGN? , , Albert EinsteinMechanicaldesign is creating new devices or improving existing ones in an attempt to provide the best, or optimum design consistent with the constraints of time,money, and safety Imagination is more important than knowledge, for knowledge is finite whereas imagination is infinite.Albert Einstein 99% Genius is one percent inspiration and 99 percent perspiration Thomas Ediso

?

DESIGN VS. ANALYSIS

DESIGN LEVELS(1) Adaptive design (2) Development design(3) New design

DESIGN PROCESS

I. PROBLEM DESCRIPTION(1) . Recognize needs and set goals what must be done to resolve the need.(2) - ()Perform market analysis what is already available in the market and what they have to offer.(3) ()-() ()/ Establish a function analysis need statement and where the problem/need stands in the whole system(4) () Identify all specifications and constraints list of all pertinent data and parameters that tend to control the design and guide it toward the desired goal.

II. PRELIMINARY DESIGN(1) Various concepts for the system are studied. (2) () Various subsystems are identified and their preliminary designs estimated (Brainstorming).III. ANALYSIS(1) : Evaluation of alternatives:Through a discussion and evaluation process, the design is selected.(2) : () Analysis and Optimization:Test the selected design against the physical laws.IV. PROTOTYPE(1) / : (). Experiment and/or Testing The design on paper is transformed into a physical reality.The iterative process has to be continued until an acceptable system has evolved. V. COMMUNICATION(1) - Marketing Selling the idea to management or the client. ADAPTIVE DESIGN

DEVELOPMENT DESIGN

NEW DESIGN

:, . . , (Optimize) . 1. 2. ()(performance)3. ()4. 5. ()6. 7. 8. 9. 10. , 11. 12. 13. (Appearance) (attractive) , . :1. 2.(Sketch Drawing), 3. (The free Body Diagram) .4. : , (Beam Deflection), (Buckling of Column) .5. .6. , . , .7. .8. , .9. ().10.(), / ( ).11. . , (), .

()

a. , , b. , c. , a. , b. , , c. , d. , .

1. 2. / / 3. 4. 5.

. Production Design Specification(PDS)

1. 2. . 3. 4. ()5. 6. 7. 8. 9. 10. 11. 12. , 13. .14. .15. 16. 17. 18. .19. 20. .21. 22. 23.24. EXAMPLE OF DR&O Hybrid Bicycle Design

1., () Must be driven by electric motor, by human power or the combination of both (as a consequence, it needs a one-way clutch at the foot pedal).2. 250W The power of the electric motor must be less than 250 Watt.3. , During braking the electric motor should be off automatically.4. 50 km The battery must be able to store electric energy for the distance of at least 50 km.5. 400 US$ Maximum target price is 400 US$. 6. 100,000 Production target is 100,000 bicycles per year.7. Attractive appearance since the target consumers are mostly women.8. 25 kg Maximum target weight is 25 kg. Automatic Hand-Brake Design :

1. Must function when the car stops. 2. Must not function when the car runs. 3. Must have sufficient brake pressure on the sloping road. 4. Must be able to release the hand-brake smoothly and once released the car must not move backward on the sloping road. 5. Should have a spare mechanic hand-brake in case the automatic brake fails. 6. Should possess high reliability. 7. 1,000 US$/ The additional cost for the automatic hand-brake system should be less than 1,000 US$ per unit. 8. 10,000 / Expected production is 10,000 units per year. 9. Electronic system and sensors are expected to be developed by other companies on a sharing cost basis. 10. 6 Should be developed in less than 6 months. EVALUATION METHOD

, . , , : , : ,

PUGHDECISION MAKING OR PUGH METHOD1. () Choose or develop the criteria for comparison. first method second method2. Select the Alternatives to be compared.3. () Generate Scores.4. Compute the total score.DECISION MAKING OR PUGH METHOD

(DESIGN IMPROVEMENT). , , , (well-liked) . , .EXAMPLE OF DESIGN IMPROVEMENT

GANTT CHART . , :(1) Non-routine tasks,(2) / Distinct start/finish dates,(3) (///)Resource constraints (time/money/people/ equipment).: . . (, , )Tasks: are activities which must be completed to achieve project goal. Break the project into tasks and subtasks. Tasks have start and end points, are short relative to the project and are significant (not going to library, but rather, search literature).: . . -: , , Milestones: are important checkpoints or interim goals for a project. Can be used to catch scheduling problems early. Name by noun-verb form, e.g. report due, parts ordered, prototype complete.

Steps in preparing a Gantt chart:1. () () List all events or milestones in an ordered list, whenever possible.2. () ()Estimate the time required to establish each event (remember it is an estimate).3. () List the starting time and end time for each event.4. Represent the information in a bar chart.

GENERAL REQUIREMENTS IN TECHNICAL WRITING1. Paper Type2. Margins3. Print Requirements4. Line Spacing5. Language6. () Paragraphs and Sections7. , Caption for Figures, Tables and Equations8. Quotations9. Footnotes10. Binding11. Miscellaneous12. Ethical Issues

EXAMPLE OF CASE STUDYDesign of Water Pump

1. 2. 3. 4.5. 100,000 km Engineering Analysis :

25-40% 20-25% 40-50%

zu - (kJ/hour)B - (kg/hour)Hu - (kJ/kg)

bsp - (8 (g/kWh)Peff - (kWh)

ab = (kJ/hour)F = 0.25 m = ab /T .c m = (kg/hour) T = (oK) c = (kJ/kgoK) Q = m / Q = (m3/hour) = (kg/m3), . , . . . . , . , . () . ()

Alternative Production of the Pump HousingCriteria Grey Cast IronAl Die Casting

Strength Datum S

Weight Datum + + +

Cost Datum _

Assembly Datum +

Total Evaluation Better

Alternative Production of the Pump ImpellerCriteriaGrey Cast IronAl Die CastingStamping

Strength Datum S +

Weight Datum + + + + +

Cost Datum _ +

Assembly Datum + +

Total Evaluation Better Best

(Detailed Drawing of the Pump Housing)

(Detailed Drawing of the Pump Impeller )

(Detailed Drawing of the Hub)

:1. 2. 3. 4. : 32H7 :

: : ; ; ; . , , : 15/09/2014Re: (322ME321)

(Title of the Project)______________,______________________________________________

()(Project summary)

(Introduction)()(Problem descrition)()(Major Assumption)()(Expected Outcomes)()(Budget Summary)()(Conclusions)()

(), , , . . () . () . ()

ORAL PRESENTATIONS1. Analyze the Situation2. Planning Your Presentation3. Self-Evaluation TestORAL PRESENTATIONS