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ME 312 – Machine Design
Dr. Bilal A. Siddiqui,
Asst. Prof (ME)
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
2/2/2017
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Course Outline
 Basic criteria of design of machine parts
 Determination of permissible and actual stresses, factor of safety etc.
 Design of …..
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
2/2/2017
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Course Outline
 Pre-requisites
 Mechanics of Materials-I (ME-212)
 Mechanics of Materials-II (ME-213)
 Textbook
 Mechanical Engineering Design by J. E. Shigley, McGraw Hill
 References
 Machine Design, An Integrated Approach by R. L. Norton, McGraw Hill.
 Design of Machine Elements by M. F. Spotts, Prentice Hall
 Fundamentals of Machine Component Design, by R. C. Juvinall & K. M. Marshek, John
Wiley
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
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Course Outline
 Evaluation Methods
 Course Objectives
Homeworks
Project
Quizzes
Major Exams
Final Exam
6.5%
7.0%
6.5%
30.0%
50.0%
 Design common machine elements and to gain experience in solving design problems.
 Prepare professional quality solutions and effectively communicate the results of analysis
and design.
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
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What is a (Mechanical) Machine
 A machine is a tool containing one or more moving parts that uses energy to
perform the action it is designed for.
 Tool: …well, open to interpretation. Anything that makes life easy
 Moving parts: simple machines?
 Energy: chemical, electrical, mechanical, thermal etc.
 Action: transport, manufacturing, destroying etc.
 Design: ME-312
Newtonian Mechanics
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
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Simple Machines
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
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Design Example (simple lever)
𝐸𝑓𝑓𝑜𝑟𝑡 𝐴𝑟𝑚
𝐿
 Mechanical Advantage = 𝑅𝑒𝑠𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝐴𝑟𝑚 = 𝐿𝑒
𝑟
 Constraints
 Strength of material
 Strength of Fulcrum joint
 Bearing strength
 Effort force available
 Maximum and minimum arm lengths (Le>Lr)
 Cost
Design Space
Le
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Spring 312 ( Copyrights' Bilal Siddiqui 2015
Lr
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Compound Machines
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Complex Machines
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Really Complex Machines
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Nature & Engineering Design
T=0
T= 1503
AD
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
T= 1903
AD
T= 2003
AD
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So what is the best Design
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The Design Cycle
Identify need
Survey existing
solutions
Define Problem
(constraints,
requirements…)
Evaluate Solutions
Solutions
(simulations)
Develop and
Testing and further
Presentation and
Prototype Solution
improvement
Communicate
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
optimization
Select Possible
Select ‘Best’ Solution
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Design Stages
 Initial Design
 Preliminary Design
 Detailed Design
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
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Course Project…..
 1. Define need
DESPERATE: We need to replace these
guys with these…
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
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Spring 312 ( Cpoyrights Bilal Siddiqui 2015
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Course Project…..
 1. Survey Existing Solutions
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2. Offshoot Ideas
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3. Generate Ideas (Brainstorm)
 Come up with several concepts
 New
 …or hybrid
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Define the Problem
 Which disabilities?
 What sizes?
 Constraints?
 Regulations?
 Business model?
 Which parts are required?
 Who are the competitors?
 Our advantage?
Spring 312 ( Cpoyrights Bilal Siddiqui 2015
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