Week 12_MIET2093_Revision

Prévia do material em texto

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MIET2012 
1 
Lecture 12: Revision 
MIET2093 
Computer Aided Design 
 
by: 
Dr. Toh Yen Pang 
tohyen.pang@rmit.edu.au 
9925 6128 
B251.3.22 
School of Aerospace, Mechanical & Manufacturing Engineering 2 RMIT University©2014 
Teaching Schedule 
Teaching 
Week 
Lecture Topics Tutorial Topics Assessments/Tasks 
Week 12 Summary Assembly Workbench Quiz 5 
Group Project submission 
Exam 
periods 
Final Exam (Saturday, 1st Nov; 
10:00-13:00pm 
Building 56, level 4 PC labs 
83,85,86,89,90) 
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School of Aerospace, Mechanical & Manufacturing Engineering 3 RMIT University©2014 
Written Report 
Introduction 
Report due in Week 12 (Friday 17th Oct, 5pm) 
(Template given)−leader to submit e-report. pdf and 
CATIA files online 
 Results 
Methodology 
Contents: (Refer to Week 9 lecture notes) 
 Discussion 
 Conclusions 
Abstract 
‘MyRMIT Studies’: 
 Group Project à Project Submission 
School of Aerospace, Mechanical & Manufacturing Engineering 4 RMIT University©2014 
Final Exam (35%) 
1st Nov (Saturday) 
10:00am-1:00pm 
Labs (Building 56, level 4) 
Topics: 
•  Section Views 
•  Dimension & Tolerance 
•  Assemblies & Technical Drawing 
•  Reverse Engineering 
•  Rapid Prototype 
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School of Aerospace, Mechanical & Manufacturing Engineering 5 RMIT University©2014 
Course Experience Survey (CES) 
 
www.rmit.edu.au/ssc 
School of Aerospace, Mechanical & Manufacturing Engineering 6 RMIT University©2014 
Course Experience Survey (CES) 
 •  email: to collect student feedback for improvement in learning and 
teaching	
•  Individual student feedback remains confidential	
•  Good teaching score (GTS) used for performance review of lecturers 
and tutors (> 70% required for undergraduate courses)	
•  Eg. I am learning a lot of new skills in this course. Each question is 
measured against a 5 point scale ranging from ‘Strongly Disagree’ to 
‘Strongly Agree’.	
•  Marking 1-3 (maybe / not sure) results in < 70% à we have failed your 
expectations for this course	
•  Please give constructive feedback when criticising	
•  Any constructive comments are welcome.	
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School of Aerospace, Mechanical & Manufacturing Engineering 7 RMIT University©2014 
What aspects of this course are 
in most need of improvement? 
•  In Test 1 many of the questions that were asked I had not seen before. 
•  The inability to access the CATIA program at home makes studying difficult 
unless in the computer labs. 
•  The exam on a weekend is ridiculous. 
•  Quality of Lectures 
•  As beginners of CAD, we should be given more enough practise classes 
before the quizes and also assignments 
•  Late night lecture 
•  More demonstrations in CATIA, addtitional lab time 
Examples from Sem 1 
School of Aerospace, Mechanical & Manufacturing Engineering 8 RMIT University©2014 
What are the best aspects of this 
course? 
•  Being able to visualize objects and 3D models as well as using Catia 
•  To learn how to do engineering drawing, so that we can apply it in the future 
when working 
•  they best aspect of this course is working in a group and creating your 
own design using computer design software. 
•  The weekly tutorials or practical classes are really helpful. We can ask the 
tutors for personal help 
•  Working in a group towards a common objective, ie. the group project 
Examples from Sem 1 
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MIET2012 
Section view 
School of Aerospace, Mechanical & Manufacturing Engineering 10 RMIT University©2014 
Section view 
•  Orthographic views showing all hidden lines may not be clear 
enough to describe an object’s internal details. 
•  This shortcoming can be overcome by imagining that part of the 
object has been cut away and shown in a cross-sectional view. 
This view is called a section view. 
 
http://www.khulsey.com/exploded-illustrations.html http://en.wikipedia.org/wiki/Multiview_orthographic_projection 
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School of Aerospace, Mechanical & Manufacturing Engineering 11 RMIT University©2014 
Purposes 
Clarify an internal feature. 
Facilitate dimensioning. 
Example 
Regular 
view 
Section 
view 
MIET2012 
Basic components 
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Cutting plane 
Cutting plane is an imaginary plane that cuts through the object.	
Location and direction of a cutting plane depend on a hidden feature that 
is needed to be revealed.	
A section view is obtained by viewing the object after removed the cover 
up part in the direction normal to the cutting plane.	
Cutting 
plane 
Example 
Section view 
School of Aerospace, Mechanical & Manufacturing Engineering 14 RMIT University©2014 
Section lining : Purpose 
Section lines or cross-hatch lines are added to a section 
view to indicate surface that are cut by a cutting plane. 
Examples 
Section view 
without section lines 
Section view 
with section lines 
Visible surfaces and edges behind the cutting plane are drawn in a section view. 
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MIET2012 
Types of 
section 
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Types of section 
1. Full section 
2. Offset section 
3. Half section 
4. Broken-out section 
5. Revolved section (aligned section) 
6. Removed section (detailed section) 
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Conventional practice : Treatment of a hidden line 
Hidden lines are usually omitted within the section lined area. 
Example 
Hidden lines 
are omitted. 
Hidden lines 
present. 
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Full section : Concept & example 
A section view is made by passing the straight cutting 
plane completely through the part. 
Example 
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Half section : Concept & example 
A section view is made by passing the cutting plane halfway 
through an object and remove a quarter of it. 
Example 
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Comparison of a different section techniques	
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Section view 
•  All visible edges and contours behind the cutting plane should be shown. 
•  Hidden lines should be omitted in section views. 
•  A section view should always be bounded by a visible outline. 
•  There should be no lines in the hatched area. 
•  Section lines should be in the same direction. 
•  Use standard section lines (hatch) to show materials. 
School of Aerospace, Mechanical & Manufacturing Engineering 22 RMIT University©2014 
A section view usually shows __________ details. 
 a. exterior 
 b. interior 
 c. profile 
 d. foreshortened 
Match&the&section&view&for&the&object&shown&the&pictorial.&&
&
Given&
&&
&& A&
&&
&& B&
&&
&& C&
&&
&& D&
 
 
 
 
Example Multiple choice questions	
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School of Aerospace, Mechanical & Manufacturing Engineering 23 RMIT University©2014 1 2 3 5 64 7 A3
1 2 3 4 5 6 7 8
A
B
C
D
E
F
A
B
C
D
E
F
Connecting Rod Side 1
DESIGNED BY:
Thierry Perret-Ellena
DATE:
2014-05-21
QUANTITY:
1 Off
CHECKED BY:
TPE
DATE:
THIRD ANGLE PROJECTION SCALE:
1:2 1/1
SHEET:
DOCUMENT TITLE:GENERAL TOLERANCE
ISO 2768 - mK
LINEAR DIMENSIONS
0.5<t 3 0.1
3<t 6 0.1
6<t 300.2
30<t 120 0.3
120<t 400 0.5
ANGULAR DIMENSIONS
t 10 1°
10<t 50 ±30'
50<t 120 ±20'
120<t 400 ±10'
400<t ±5'
This drawing is our property; it can't be reproduced or communicated without our written agreement.
NEXT ASSY:
ESA-A001
DRAWING REVISION
DESCRIPTION DATE APPROVAL
01 1
ITEM REF QTY DESCRIPTION MATERIAL/DRAWING NO. REMARKS/SUPPLIER/CATALOG NO.
SIGNATURE:
FINISH:
DOCUMENT TYPE:
Part Drawing
400<t 1000 0.8
1000<t 2000 1.2
(SHARP EDGES BROKEN
(GENERAL TOLERANCE ISO 2768 - mK
DRAWING NUMBER:
CRS1-P001
REVISION:
001
PROJECT:
...
260
2
4
3
8
7R2x 7R2x 
BB
A
A
C
41
59
80R
80R
80R
40R
72.31
3
6
1
8
135
116
38
41
Section view B-B
Scale: 1:2
D
D
5R4x Section view A-A
Scale: 1:2
1
(
2
x
)
 
4
5
Detail C
Scale: 3:2
Auxiliary view D
Scale: 1:2
100.31
50.16
19
122x x1.75
84
Example Exam question (Part C1)	
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Example Marking Rubrics	
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MIET2012 
Threaded Fasteners 
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Symbols for Drilling Operations 
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School of Aerospace, Mechanical & Manufacturing Engineering 27 RMIT University©2014 
Dimensioning 
 
School of Aerospace, Mechanical & Manufacturing Engineering 28 RMIT University©2014 
Dimensioning 
•  Before an object can be built, complete information about both the 
size and shape of the object must be available. 
•  The exact shape of an object is communicated through orthographic 
drawings, which are developed following standard drawing 
practices. 
•  The process of adding size information to a drawing is known as 
dimensioning the drawing. 
•  A dimension is a numerical value used to define the size, location, 
geometric characteristics of a part or feature. 
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School of Aerospace, Mechanical & Manufacturing Engineering 29 RMIT University©2014 
Applying the dimensioning 
components 
Extension line, dimension 
line and dimension number 
Mostly done by using 
Leader line and note 
The appropriate method depends on the object’s features. 
27 φ10 45 o 
Notes 
Detail of a local note depends on the object’s features. 
Example Example 
School of Aerospace, Mechanical & Manufacturing Engineering 30 RMIT University©2014 
Dimensioning components 
Extension lines 
Dimension lines (with arrowheads) 
Leader lines 
Dimension numbers 
(or dimension figures) 
Notes 
20 
13
 123 o 
φ10 
- indicate the location on the 
 object’s features that are dimensioned. 
- indicate the direction and extent of a 
 dimension, and inscribe dimension 
 numbers. 
- indicate details of the feature 
 with a local note. 
- local or general note 
R16 
Example 
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School of Aerospace, Mechanical & Manufacturing Engineering 31 RMIT University©2014 
1 2 3 5 64 7 A3
1 2 3 4 5 6 7 8
A
B
C
D
E
F
A
B
C
D
E
F
CASTOR
DESIGNED BY: DATE:
2/10/14
QUANTITY:
1 Off
CHECKED BY:
TPE
DATE:
THIRD ANGLE PROJECTION SCALE:
1:1 1/1
SHEET:
DOCUMENT TITLE:GENERAL TOLERANCE
ISO 2768 - mK
LINEAR DIMENSIONS
0.5<t 3 0.1
3<t 6 0.1
6<t 30 0.2
30<t 120 0.3
120<t 400 0.5
ANGULAR DIMENSIONS
t 10 1°
10<t 50 ±30'
50<t 120 ±20'
120<t 400 ±10'
400<t ±5'
This drawing is our property; it can't be reproduced or communicated without our written agreement.
NEXT ASSY:
SIGNATURE:
FINISH:
DOCUMENT TYPE:
Part Drawing
400<t 1000 0.8
1000<t 2000 1.2
DRAWING NUMBER:
2
REVISION:
001
PROJECT:
J. ONEIL DONNELLON
Front view
Scale: 2:3
30
110
50
12
8
51.63
6
0
3
88 8
B
B
D
Top view
Scale: 2:3
1
8
56
15
2
6
3
8
4
6
A A
Section view A-A
Scale: 2:3
5R
2R 3R
5R
2
.
4
117.78
28.63
4
5
.
8
2
5R
Section view B-B
Scale: 2:3
41.2
46
C
Detail C
Scale: 4:3
1R
Detail D
Scale: 4:3
24
.6
6
4R
5R
23.58
10
5R
0.48
12.73
1R
3R
2
.
7
3
1R
3R
28.08
3R
Example Exam questions (Part C3)	
MIET2012 
Assembly Modeling 
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School of Aerospace, Mechanical & Manufacturing Engineering 33 RMIT University©2014 
Introduction 
Assembly modeling enable the operator to combine 
components to create a 3D parametric assembly model. 	
Assemblies, when brought in as components, are now 
considered subassemblies in the new larger assembly.	
School of Aerospace, Mechanical & Manufacturing Engineering 34 RMIT University©2014 
Create an assembly 
Any assembly can be thought of as a hierarchy of 
subassemblies and/or parts and can be represented in a tree 
structure.	
Construction an assembly begin with selecting a base 
component because of its central role in defining the overall 
assembly.	
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School of Aerospace, Mechanical & Manufacturing Engineering 35 RMIT University©2014 
Assembly workbench 
School of Aerospace, Mechanical & Manufacturing Engineering 36 RMIT University©2014 
Save Management 
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School of Aerospace, Mechanical & Manufacturing Engineering 37 RMIT University©2014 
Example Marking Rubrics	
School of Aerospace, Mechanical & Manufacturing Engineering 38 RMIT University©2014 
Drawing Sheet 
http://en.wikipedia.org/wiki/Engineering_drawing 
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School of Aerospace, Mechanical & Manufacturing Engineering 39 RMIT University©2014 
Definition (1/3)	
Working drawing is a set of specialized engineering 
drawing specifying the manufacture and assembly of a 
product based on its design. 	
Working drawing	
Detail	
drawing	
Assembly	
drawing	
School of Aerospace, Mechanical & Manufacturing Engineering 40 RMIT University©2014 
Definition (2/2) 	
Detail drawing is a multiview representation of a 
single part with dimensions and notes. 	
Assembly drawing is a drawing of various	
parts of a machine or structure assembled in their 
relative operating positions.	
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School of Aerospace, Mechanical & Manufacturing Engineering 41 RMIT University©2014 
Detail drawing conveys the information and 
instructions for manufacturing the part.	
4. functional relationship among various ���
 components.	
1. completed shape of the product.	
2. overall dimensions.	
Purpose	
Assembly drawing conveys	
3. relative position of each part.	
MIET2012 
Detail Drawings 
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School of Aerospace, Mechanical & Manufacturing Engineering 43 RMIT University©2014 
Information in Detail Drawing	
2.1 Shape description 
2.2 Size description 
2.3 Specifications 
1. General information 
2. Part’ s information 
Title block 
Object’s 
views 
Notes 
3. Dimensions and Tolerance 
4. Material designation 
School of Aerospace, Mechanical & Manufacturing Engineering 44 RMIT University©2014 
General Information in Title block	
Ø  Name of company	
Ø  Title of drawing (usually part’s name)	
Ø  Drawing sheet number	
Ø  Name of drafter, checker	
Ø  Relevant dates of action���
 (drawn, checked, approved etc.)	
Ø  Revision table	
Ø  Unit	
Ø  Scale	
Ø  Method of projection	
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School of Aerospace, Mechanical & Manufacturing Engineering 45 RMIT University©2014 
Drawing Template 
1 2 3 5 64 7 A3
1 2 3 4 5 6 7 8
A
B
C
D
E
F
A
BC
D
E
F
...
DESIGNED BY:
...
DATE:
...
QUANTITY:
1 Off
CHECKED BY:
TPE
DATE:
THIRD ANGLE PROJECTION SCALE:
1:1 1/1
SHEET:
DOCUMENT TITLE:GENERAL TOLERANCE
ISO 2768 - mK
LINEAR DIMENSIONS
0.5<t 3 0.1
3<t 6 0.1
6<t 30 0.2
30<t 120 0.3
120<t 400 0.5
ANGULAR DIMENSIONS
t 10 1°
10<t 50 ±30'
50<t 120 ±20'
120<t 400 ±10'
400<t ±5'
This drawing is our property; it can't be reproduced or communicated without our written agreement.
NEXT ASSY:
...
DRAWING REVISION
DESCRIPTION DATE APPROVAL
01 1
ITEM REF QTY DESCRIPTION MATERIAL/DRAWING NO. REMARKS/SUPPLIER/CATALOG NO.
SIGNATURE:
FINISH:
DOCUMENT TYPE:
Part Drawing
400<t 1000 0.8
1000<t 2000 1.2
(SHARP EDGES BROKEN
(GENERAL TOLERANCE ISO 2768 - mK
DRAWING NUMBER:
...
REVISION:
001
PROJECT:
...
School of Aerospace, Mechanical & Manufacturing Engineering 46 RMIT University©2014 
Balloon, BOM 
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School of Aerospace, Mechanical & Manufacturing Engineering 47 RMIT University©2014 
Part List (BOM) 	
NO. PART NAME REQD. MATL. & NOTE 
1 SUPPORT 2 Cast Iron 
2 SHAFT 1 Stainless Steel 
3 SET SCREW 1 Stainless Steel, M3 HEX SOCK CUP PT 
Locate above or beside the title block. 
Fill the table from the bottom. 
School of Aerospace, Mechanical & Manufacturing Engineering 48 RMIT University©2014 
Describe how CAD is used to create working drawings. (2 
marks) 
CAD is used in all aspects of creation of working 
drawings. Drawing tools are used to create the part 
geometry, dimensioning tools the dimensioning and 
tolerancing information, while text tools are used for 
notes and titleblock information. 
Example short answer question	
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School of Aerospace, Mechanical & Manufacturing Engineering 49 RMIT University©2014 
Enhance Scene	
School of Aerospace, Mechanical & Manufacturing Engineering 50 RMIT University©2014 
Generate Numbering and BOM	
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School of Aerospace, Mechanical & Manufacturing Engineering 51 RMIT University©2014 
1 2 3 5 64 7 A3
1 2 3 4 5 6 7 8
A
B
C
D
E
F
A
B
C
D
E
F
Wheel Assembly
DESIGNED BY:
...
DATE:
...
QUANTITY:
1 Off
CHECKED BY:
TPE
DATE:
THIRD ANGLE PROJECTION SCALE:
1:1 1/1
SHEET:
DOCUMENT TITLE:GENERAL TOLERANCE
ISO 2768 - mK
LINEAR DIMENSIONS
0.5<t 3 0.1
3<t 6 0.1
6<t 30 0.2
30<t 120 0.3
120<t 400 0.5
ANGULAR DIMENSIONS
t 10 1°
10<t 50 ±30'
50<t 120 ±20'
120<t 400 ±10'
400<t ±5'
This drawing is our property; it can't be reproduced or communicated without our written agreement.
NEXT ASSY:
...
DRAWING REVISION
DESCRIPTION DATE APPROVAL
01 1
ITEM REF QTY DESCRIPTION MATERIAL/DRAWING NO. REMARKS/SUPPLIER/CATALOG NO.
SIGNATURE:
FINISH:
DOCUMENT TYPE:
Part Drawing
400<t 1000 0.8
1000<t 2000 1.2
(SHARP EDGES BROKEN
(GENERAL TOLERANCE ISO 2768 - mK
DRAWING NUMBER:
...
REVISION:
001
PROJECT:
...
Isometric view
Scale: 1:4
Isometric view
Scale: 1:7
1
2
3
4
5
Bill of Material: WA-
A001_Wheel_Assembly
Quantity Part Number Number
2 BH-
P001_Bearing_Housing
1
1 MS-
P001_Machined_Shaft
2
1 ISO 2491 KEY
100x20x8 THIN
PARALLEL FORM A
3
1 WH-P001_Wheel 4
1 WS-
P001_Wheel_Support
5
Example Exam questions (Part C2)	
School of Aerospace, Mechanical & Manufacturing Engineering 52 RMIT University©2014 
Example Marking Rubrics	
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School of Aerospace, Mechanical & Manufacturing Engineering 53 RMIT University©2014 
What is Reverse Engineering?	
Reverse engineering (RE) is a process of measuring, 
analyzing, and testing to reconstruct the mirror image of an 
object or retrieve a past event 	
RE is a process by which a complex CAD model of a part 
can be constructed from point clouds scanned by various 
3D scanners 	
“Examining competitive or similar or prior products in 
great detail by dissecting them or literally taking them 
apart.” 
School of Aerospace, Mechanical & Manufacturing Engineering 54 RMIT University©2014 
Reasons for RE	
There is inadequate documentation of the original design 
or never existed	
The original manufacturer of a product no longer produces 
a product	
The original manufacturer no longer exists, but a customer 
needs the product	
To explore new avenues to improve product performance 
and features	
To gain competitive benchmarking methods to understand 
competitor's products and develop better products	
The original CAD model is not sufficient to support 
modifications or current manufacturing methods	
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School of Aerospace, Mechanical & Manufacturing Engineering 55 RMIT University©2014 
Investigation, Prediction and Hypothesis 
Concrete Experience: Function & Form 
Design Models 
Design Analysis 
Parametric 
Redesign 
Adaptive 
Redesign 
Original 
Redesign 
Reverse 
Engineering 
Modeling & 
Analysis 
Redesign 
Reverse Engineering Methodology	
School of Aerospace, Mechanical & Manufacturing Engineering 56 RMIT University©2014 
Surface and Solid Model 
Reconstruction	
One of the first steps in reverse engineering is to reconstruct the 
subject of interest from the data obtained by three-dimensional 
(3D) scanners or a direct-contact probes. 
The process can be divided into four phases: 
•  data acquisition, 
•  polygonization, 
•  refinement, and 
•  model generation. 
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School of Aerospace, Mechanical & Manufacturing Engineering 57 RMIT University©2014 
Reconstruct of Scan Data 
School of Aerospace, Mechanical & Manufacturing Engineering 58 RMIT University©2014 
Legality of RE	
Reverse engineering is used to duplicate the original 
design, or to create a new model that improves an existing 
product 
The legality of reverse engineering by an individual to 
understand the design and functionality of an invention has 
rarely been challenged, as long as it is used for: 
•  learning, 
•  changing or repairing a product, 
•  providing a related service, 
•  developing a compatible product, 
•  creating a clone of the product, and 
•  improving the product 
 
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School of Aerospace, Mechanical & Manufacturing Engineering 59 RMIT University©2014 
Is RE unethical?	
Does RE infringe on others work (or ideas)?	
Copyright Protection 
Patent Protection 
Chinese Knockoff iPad Apple iPad 
School of Aerospace, Mechanical & Manufacturing Engineering 60 RMIT University©2014 
Patent (1/2)	
Patents protect new, useful, and non-obvious inventions. 
Patent rights are territorial. 
Patent is governed by laws, regulations, policies, and 
procedures. 
An invention will be in the public domain when the 
patent’s term expires 
The patent ownership may be transferred through 
employment agreement, and/or by an express assignment, 
wherein ownership is. 
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Copyrights	
Copyrights protect an expression fixed in a tangible 
medium, such as writing, painting, or sculpting. 
All works are automatically given copyright protection the 
moment they are created 
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Example Technical Drawing & 
Patent	
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School of Aerospace, Mechanical & Manufacturing Engineering 63 RMIT University©2014 
Copyright and patents are the two key legal protections of intellectual 
property (IP) against reverse engineering. What does that copyrightprotect? What patents have traditionally protected? (2 marks) 
Copyrights protect an expression fixed in a tangible 
medium, such as writing, painting, or sculpting. Or 
It pertains to the literary, musical, graphic, or artistic form 
in which the author expressed intellectual concepts. 
Patents protect whoever invents or discovers any 
new and useful product, process, machine, 
manufacture, or methods 
Example short answer question	
School of Aerospace, Mechanical & Manufacturing Engineering 64 RMIT University©2014 
What is Rapid Prototyping? 
Simulated solid model 
3D printer in process 
Final prototype part 
Rapid prototyping systems allow designers to quickly convert 
a conceptual design idea (from 3D Computer Aided Design 
(CAD) data) into a physical part for mockup and testing 
It helps engineers to visualize the design drawing and 
computer modeling 
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School of Aerospace, Mechanical & Manufacturing Engineering 65 RMIT University©2014 
Why Rapid Prototyping? 
Increasing number of variants of products.	
Rapid Prototyping decreases development time by allowing 
corrections to a product to be made early in the processà Enable 
other teams to look at the product early in the design process, 
changes can be made while they are still inexpensive. The trends 
in manufacturing industries continue to emphasize the following: 	
Increasing product complexity.	
Decreasing delivery time. 	
Rapid Prototyping improves product development by 
enabling better communication in a concurrent engineering 
environment. 	
School of Aerospace, Mechanical & Manufacturing Engineering 66 RMIT University©2014 
Rapid Prototyping Process 
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School of Aerospace, Mechanical & Manufacturing Engineering 67 RMIT University©2014 
©2007 John Wiley & Sons, Inc. M P Groover, 
Fundamentals of Modern Manufacturing 3/e 
Classification of RP Technologies	
There are various ways to classify the RP techniques that have 
currently been developed 	
The RP classification used here is based on the form of the 
starting material: 	
Liquid-based	
Solid-based	
Powder-based	
School of Aerospace, Mechanical & Manufacturing Engineering 68 RMIT University©2014 
©2007 John Wiley & Sons, Inc. M P Groover, 
Fundamentals of Modern Manufacturing 3/e 
Stereolithography: (1) at the start of the process, in which the 
initial layer is added to the platform; and (2) after several layers 
have been added so that the part geometry gradually takes form.	
Rapid Prototyping Systems: 
Stereolithography Process 	
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School of Aerospace, Mechanical & Manufacturing Engineering 69 RMIT University©2014 
Fused Deposition Modeling 	
•  A gantry robot controlled extruder 
head moves in two principle directions 
over a table 
•  Table can be raised or lowered as 
needed 
•  Thermo plastic or wax filament is 
extruded through the small orifice of 
heated die 
•  Initial layer placed on a foam 
foundation with a constant rate 
•  Extruder head follows a predetermined 
path from the file 
•  After first layer the table is lowered 
and subsequent layers are formed 
Fig : (a)Fused-deposition-modeling process. 
(b)The FDM 5000, a fused-decomposition-
modeling-machine. 
School of Aerospace, Mechanical & Manufacturing Engineering 70 RMIT University©2014 
3-D Printing (1/2)	
Similar to ballistic particle manufacturing 
Fig:Three dimensional printing process 
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School of Aerospace, Mechanical & Manufacturing Engineering 71 RMIT University©2014 
©2007 John Wiley & Sons, Inc. M P Groover, 
Fundamentals of Modern Manufacturing 3/e 
RP Applications 	
•  Applications of rapid prototyping can be classified 
into three categories: 	
1.  Design 	
2.  Engineering analysis and planning 	
3.  Tooling and manufacturing	
School of Aerospace, Mechanical & Manufacturing Engineering 72 RMIT University©2014 
The following are the main roles and functions of prototype in the 
product development process, except: 
 
A. Ergonomics and visual trials 
B. Synthesis and integrations 
C. communication and interaction 
D. service application 
Example Exam questions