SchF09x - San Jose State University

architectgeorgeMechanics

Oct 31, 2013 (3 years and 7 months ago)

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SAN JOSE STATE UNIVERSITY

Mechanical and Aerospace Engineering Department


ME 157

-

Mechanical System Design











Fall

2009

Instructor:

Dr. Ken Youssefi





Office: IS106, phone: (510) 642
-
4483

Class room:

E 331













Office hrs. :
MW
-

TBA




Class time:

Lecture
-

MW 10:30
-

11:45









Class

code:

41772







Email:
kyoussefi@aol.com

Final Exam:

Friday Dec. 11, 9:45
-

12:00




Course website: www.engr.sjsu.edu/mae


Sept. 3 (Th.)
-

Last day to drop
, Sept. 11(Fri.)


last day to add








COURSE OBJECTIVES:

Introduction to the mechanical design process: Design specification development, conceptual design, and
product design
process. Application of the fundamentals from statics, dynamics, strength of materials, static and
fatigue failure theories are applied to specific machine components. Emphasis will be placed on the integration
of the mechanical engineering disciplines and

systematic integrated approach to design of machine elements
and systems. Plastics and composite materials in design will be introduced. Also Introduction to fracture
mechanics will be covered in this course. The required group design project will increas
e the students'
understanding of the design process

and dynamics of team work
. 3 units.


Prerequisite:

ME154,

Co
-
req
uisite
:

ME110

and ME147



Required
Textbook
s
:



1


Norton, R.L.,


Machine Design”,
3
rd

ed., Prentice Hall, 2006


2


Ullman, D.G.,
“The Mechanical Design Process”, 3th edition, McGraw
-
Hill, 2003


3


Lecture note
s (PowerPoint, see the website)








References:



Baumeister, Avallon, et al,
Marks Handbook for Mechanical Engineers
.



American Society for Metals,
Metals

Handbook
, Vols. 8
& 10.



Juvinall and Marshek,
Fundamentals of Machine Components Design
, Wiley, 2001.



Roark,
Formulas for Stress and Strain
, 6th ed, McGraw Hill, 1996.



Rolfe and Barsom,
Fracture and Fatigue Control in Structure
, Prentice Hall, 1996.



Dudley, W.D.,
Practical
Gear Design
, McGraw Hill, 1984



Ertas, Atila and Jones, Jesse,
The Engineering Design Process
, Wiley, 1993.



Shigley,

Mischke,
and Budynas
,
Mechanical Engineering Design
, 7
th

Edition,

McGraw Hill, 2004
.


Homework
:

homework
problems are assigned a week befo
re due date.
Homework must meet a reasonable

standard of clarity and

neatness
.
No late homework will be accepted

without the consent of the instructor
.

Homework problems will

be reviewed in the class

and the solution will be posted on the Mechanical and

Aerospace Engr. (mae) website

(
www.engr.sjsu.edu/mae
, select faculty and then faculty web pages).


Design Project:

students
,

working in groups
,

are responsible for a design project, see the separate handout.


Grading: 1
st

midterm 15%
,
2
nd

exam 20%, Final Exam 25%, Project 25
%, Homework 15%



Final course grade is determined using a normal distribution curve. Grade distribution:





Grade A

average plus one standard deviation and higher





Grade B

average
plus ½ standard deviation





Grade C+

average





Grade C
-

average minus ½ standard deviation





Grade F

average minus one standard deviation and lower

Academic Integrity Statement (University Policy)

“Your own commitment to learning, as evidenced by you
r enrollment at San Jose State University and the
University’s Integrity Policy, requires you to be honest in all yur academic course work. Faculty members are
required to report all infractions to the Office of Judicial Affairs.” All students should revie
w the Academic
Integrity Policy on cheating and plagiarism, copy of the policy can be found on the website at
http://sa.sjsu.edu/judicial_affairs/index.html


Campus policy in compliance with th
e Americans with Disabilities Act

“If

you need course adaptations of accommodations because of a disability, or if you need special arrangements
in case the building must be evacuated, please make an appointment with me as soon as possible, or see me
durin
g office hours. Presidential Directive 97
-
03 requires that students with disabilities register with DRC to
establish a record of their disability.”


College and Department Policy

You are responsible for understanding the policies and procedures for
add/drop, academic renewal,
withdrawals, incomplete grade, classroom behavior, and other policies described in the catalog. Please read
your catalog thoroughly.


Course Objectives
:




To introduce the Mechanical Engineering Process, design flow chart, identification of a need,
specification and requirements, conceptual design, evaluation of concepts, product design, human factor.



To design and select (from catalogs) various machine com
ponents such as: mechanical springs, contact
bearings, brakes and clutches, gears, shafts.



To introduce linear elastic fracture mechanics and design based on fracture toughness.



To have students work as a team to design a mechanical system and prepare a
technical report.


Student Learning Objectives


The students should be able to:



Select a project to design a new product or modify an existing product, based on market research, and
carry it through the design process up to building the CAD prototype and
evaluation for function.



Determine the location and magnitude of the maximum stress on a component.



Estimate the value of the stress concentration factor and apply it correctly to the stress component.



Design a machine component to guard against yieldin
g or fracturing under static load using the
appropriate failure criteria and safety factors.



Design a machine component to guard against fatigue failure, either using the classical approach or the
fracture toughness approach.



Identify factors that have a
n influence on the design and selection of different machine components.



Design a spring, given the applied load and desired deflection, and select it from catalogs.



Select a suitable bearing from catalogs by knowing the bearing loads (radial and thrust)
, bearing life and
reliability.



Design a gear reducer (planetary or conventional) to obtain a certain output speed and use AGMA code
to determine the allowable load and select a suitable gear from catalogs.



Aware of the choices they have when it comes to

material selections: metals as compared to composites
or plastics.






COURSE SCHEDULE


Week/Date

Subject









Reading Assign.(chapter
)

& HW


1

8/24

Introduction, course organization







(1,2)
-

Ullman


8/26

D
esign project discussion









2

8/31

An overview of Design Process
and Concurrent Engineering




(5,6)


Ullman, Notes



9/2

Product development planning, identification of a need,










Understanding customer needs



design group formation




HW 1 (ideas)





3

9/7

Monday, Holiday


Labor Day







(6)


Ullman, Notes


9/9

Benchmarking (case studies) and Engineering Specifications







4

9
/14

Conceptual Design phase; concept generation
(
intuitive and logical

(7)


Ullman, Notes



methods
)
,

brainstorming and brain
-
writing.








9
/16

Concept selection; estimati
ng technical feasibility,
Pugh’s method




(8)


Ullman, Notes





Design project discussion



project idea





HW 2 (mission stmt)



5

9/21

Design for manufacturing and assembly; concept of theoretical


(12)


Ullman, Notes



minimum number of parts, design guidelines











9/23

Physical prototype building and testing
, human factors in design



Notes



Design project specifications and

requirements





HW 3 (specs)

6

9/28

Review; fatigue failure theories
, example and design considerations


(5,6)


Norton, Notes


9/30

Midterm exam 1






7

10/5

Gears; fundamental law, standard tooth specification,



(11,1
2)

Norton



kinematics

of gear tooth




10/7

Gear trains: conventional, planetary, and harmonic drives



HW 4 (fatigue)

8

10/12

Gears; force and stress analysis
,

AGMA code, design considerations

(11,12)


Norton



10/14

Bearings: Journal and rolling contact type, ball,
roller, tapered,



(10)
-

Norton



and thrust bearings.




Conceptual design due date (after presentation)







HW 5 (gear trains)

9

10/19

Furlough day


no class




10/21

Bearings; bearing life and reliability, selecting bearing from catalog.

HW 6
(gear stress)

10

10/26

Flexible elements; belt and chain drives








Notes


10/28

Flexible elements; wire rope and flexible shafts, design consideration.


HW 7 (bearings)

11

11/2

Design of mechanical springs; tension, compression,



(13)
-

Norton



and specially design springs







11/
4

Stresses, buckling and surging









12

11/9

Fatigue d
e
sign using fracture mechanics approach
,




Notes




Fracture toughness and crack propagation rate



11/11

Wednesday, Holiday


Veteran’s Day








13

11/16

Design project discussion and e
xam review



11/1
8

Midterm Exam 2




14

11/23


Thanksgiving week


no classes















11/25



15


11/30

Design using plastics
;

design considerations





Notes




Design using composite materials;
structure, properties, applications and design considerations



12/2

Design project presentation



16


12/7

Design project presentation



12/8

Tuesday


last day of instruction


Holiday and Furlough days (no class)
: Monday Sept 7
, Monday Oct. 19, Wed.
Nov. 11
,







Monday
-
Friday, Nov23
-
27 (thanksgiving
)




ky