UNIVERSITI TEKNIKAL MALAYSIA MELAKA
Reverse Engineering of Hand Phone Housing
Plastic Injection Molding
Thesis submitted in accordance with the requirements of the Universiti
Teknikal Malaysia Melaka for the Bachelor of Manufacturing Engineering
@esign)
Salbanu binti Said
Faculty of Manufacturing Engineering
May 2007
ABSTRACT
From this study of Reverse Engineering of Hand Phone Housing Plastic Injection
Molding, all the work that had been done is planned first to achieve the main target. The
overall objective of this study is to develop a methodology to reverse engineer the hand
phone wver by using certain chosen method. To approach this goal, the methodology
proposed has certain method that were identifying the product, measure the product to be
solid modeling, produce a solid model of the chosen product by using 3D scanner and
Solid Works, analyze the product by using CosmoXpress and MoldFlowXpress and lastly
to design the mould for the hand phone housing parts. As a first step, the product of
Nokia 6680 is chosen as the study product based on its popularity and the current
technology. A measmment process is done after that by using CMM and vernier caliper.
Then, solid model of Nokia 6680 is gained by using Solid Works and 3D scanner. This
study allows the learning of new knowledge such as 3D scanner and new software such
as Dr Picza and Roland Pixform 3d Scanner. From the result of the digitizing and 3D
solid model, the prototype of the hand phone is produce by the rapid prototyping
machine. The prototype is used to compare the result of the digitizing process with the
real hand phone housing. The prototype also is used to be the specimen of assembling
process. If anything happen, the prototype is referred to adjust any wrong dimension
which is lead to the assembling Slure. The mould of the hand phone housing is done
after the dimension is correct and the analysis is done. The analysis is including the
reducing part of the current design and the analysis of the mold flow process.
ABSTRAK
Daripada kajian kejuruteraan berbalik acuan suntikan plastik untuk perumah
telefon bimbit, segala kerja yang dibuat telah dirancang terlebih dahulu untuk mencapai
matlamat utama. Secara keseluruhan, kajian ini dibuat untuk menghasilkan kaedah
kejuruteraan berbalik untuk perumah telefon bimbit dengan menggunakan sesetengah
kaedah yang terpilih. Bagi mencapai matlamat ini, kaedah yang digunakan adalah
mengenalpasti produk yang akan dikaji, mengukur produk, membuat model untuk produk
yang telah dipilih menggunakan 3D Scanner dan Solidworks, menganalisa produk
dengan menggunakan CosmoXpress dan MoldFlowXpress dan akhirnya merekabentuk
acuan untuk p m a h telefon birnbit. Sebagai langkah pertama, produk Nokia 6680
dipilih untuk dikaji berdasarkan populariti dan juga teknologinya yang canggih.
Seterusnya, process pengukuran dibuat menggunakan CMM dan juga angkup vernier.
Kajian ini adalah satu pembelajaran kepada pengetahuan baru seperti 3D Scanner dan
pengisian computer seperti Dr Picza dan Roland Pixform 3d Scanner. Daripada
keputusan pengukuran dan juga model 3d, prototaip telefon bimbit dibuat menggunakan
mesin prototaip. Prototaip ini digunakan untuk process penggabungan. Jika terjadi
sebarang kesilapan,prototaip itu akan dirujuk untuk membetulkan sebarang kesilapan
pada model telefon bimbit. Acuan telefon biibit akan dibuat selepas semua ukuran tepat
dan analisis dibuat. Analisis yang dimaksudkan termasuklah pengurangan bahagian
dalam rekabentuk sebelumnya dan juga proses pengaliran ddam acuan.
CHAPTER 1
INTRODUCTION
1.1
Introduction
This reverse engineering of hand phone housing plastic injection mold is done
due to its advantages in reducing production cost and to shorten the development
process. The reverse engineering is a process that used to create 3D CAD (Computer
Aided Design) models directly fiom physical parts with accurate dimension. This is used
in order to redesign a product for better manufacturability. Usually, high technology and
modem manufacturing method is used so that a component can be quickly and
accurately reverse engineered. For a product of hand phone housing, the most important
thing that should be considered is the dimension and tolerance of each part and fatures
because each part is connected to one another and a problem will occur if the dimension
is not accurate. A good design of core and cavity is needed to produce a perfect product.
This study is focused on the methodology and the application of reverse
engineering to produce the hand phone housing mould. The application of the reverse
engineering is applied according from the first to the last process. First, a sample of the
parts or drawing must be provided. Then, the parts or object is digitized. After that, the
taken data is refined to create a 3D model. For this study, a type of hand phone housing
had been chosen from many type of the other product. The criteria of the chosen hand
phone design is based on the popularity and trend cmntly. This hand phone is chosen
based on its popularity and current trends especially among UTEM's student.
As computer-aided design has becoming more popular, reverse engineering has
become a viable method to create a 3D virtual model of an existing physical part for use
in 3D CAD, CAM, CAE and other software. The reverse engineehg process involves
measuring an object and then produces a 3D model. The physical object can be
measured using 3D scanning technologies like CMMs and laser scanners or other
handling tool such as vernier caliper. CAM is Computer Aided Manufacturing that
involves the use of computers to assist in all phases of manufacturing a product. (Serope
Kalpakjian, Manufacturing Engineering and Technology fifth edition, 2006)
1.2
The objectives of the research
The objective of the study is to develop and redesign the product with the application of
the reverse engineering process. This study is requires the student to be creative and
apply reverse e n g i n h g tools and experience high and research technology that is not
experienced in their learning education classes. The main focused in this study is to
build a core and cavity for hand phone housing with the application of reverse
engineering, to analyze the important of each part in hand phone cover to improve its
design and to analyze the injection molding process in producing the product.
The main objectives of the research are:
1. To determine the dimension of the hand phone housing by using the best existing
equipment at UTEM.
2. To select the material, based on suitable composition, properties, elasticity
modulus and poison ratio of the hand phone housing material.
3. To apply the entire related machine in UTEM in order to complete the research.
4. To generate a 3D design of the mould of the hand phone housing.
5. To produce the prototype of the hand phone housing.
13
Scope of study
a. This study will be involves the literature review of reverse engineering, mould,
injection molding, reverse engineering tools and software used.
b. To apply reverse engineering method is to obtain the solid model of hand phone
housing and detail design of existing product.
c. To study features of existing product and minimize if possible.
1.4
Problem statement
The study is done to mold for hand phone housing of Nokia 6680. The design of
the mold can reduce the production time of the product in the future beside to reduce the
cost of the production. Nokia 6680 is already existed in market, so a reverse engineering
is important to redesign the hand phone housing for other usage. A reverse engineering
is a way to reduce the development process and reduce the production costs of a product
and this will clearly show us the importance of the hand phone housing to be reverse
engineer to enhance the product.
1.5
Research
1.51
3D Laser Scanner
A Reverse engineering process of a mechanical component requires a precise
digital model of the objects to be reproduced. A 3D scanner can be used to digitize freeform or gradually changing shaped components as well as prismatic geometries whereas
a coordinate measuring machine is usually used only to determine simple dimensions of
a highly prismatic model. These data points are then processed to create a usable digital
model. The type of 3D scanner includes the laser, Destructive, Mechanical Probe, Time
of Flight and X-Ray. Within the broader topic of 3D Laser Scanning, there are two types
of device which operate in different ways and produce radically different results:
1. Triangulating 3D Laser Scanners
2. Time of Flight 3D Laser Scanners.
1.52
Coordinate Measuring Machine (CMM)
A Coordinate-measuring machine (CMM) is a device for dimensional measuring.
It is a mechanical system designed to move a measuring probe to determine the
coordinates of points on the surface of a work piece. The CMM is used to measure
dimensions which are critical in tolerance and difficult to be determine using
conventional method.
1.53
Vernier Caliper
A caliper is a device that used to measure the distance between two
symmetrically opposing sides. A caliper can be as simple as a compass with inward or
outward-facing points. The tips of the caliper are adjusted to fit across the points to be
measured, the caliper is then removed and the distance read by measuring between the
tips with a measuring tool, such as a ruler. A vernier caliper is used in the metalworking
field of mechanical engineering, and in woodworking and woodturning.
1.54
Injection Moulding
The process of injection molding is used to produce large quantities of identical
plastic items. Injection moulding is the most important plastics manufmturing process. It
produces such small products as bottle tops; sink plugs, children's toys, containers,
model kits, disposable razors and parts of cameras. It is also used to manufacture larger
items such as dustbins, and milk crates. The process can even mould such large items as
dingy hulls and kit car body shell parts. Injection moulding used to be operated by
people on the factory floor but these days it is a form of highly automated form of
production. There was not all the polymers is possible to be injection mold. This will be
later explained in the next chapter. (Product Design for Manufacture and Assembly
second edition, Winson Knight,2002)
~ H A P T E R2
LI~ERAT~TRE
REVIEW
2.1
Introduction
This chapter is all about the informatiod that related to the study such as the methods
that had been used by the others in reverse engineering process. This information is
important to this study due to the applicable of it to complete this study. This research
also is the best way to guide student with the problem encountered during the
completiori of this study. The application of the research may help student to perform a
good job in this study because of the much information to understand of what they are
looking fof.. This research review includes facts and studies of current reverse
engineering tools. The tools used are the Coordinate Measuring Machine (CMM) and
vernier caliper.
2.2
Reverse engineering
Reverse engineering is the process of extracting the knowledge of design blue- print
from anything man-made and the concept is begun before computers or modern
technology. The reverse engineering is the main study (Reversing: Secrets of Reverse
Engineering by Eldad Eilam). The research of the reverse engineering could be use to
obtained knowledge and understands the part to be design clearly. The data obtained
from this study can be used to manufacture this product in the future. Reverse
engineering usually is used by military in order to copy other nation's technology,
devices or information. (figure 2.2)
-r
PlbdUCt
+
Design Idea
4
Ikassembly
Prototype a test
4
Measwe 8
4
Product
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.c
-R=@Jw
i
Pro(olype h Tea
3.
RE Pfocfuct
Figure 2.2: Traditional Gersus reverse engineering process
(Reverse Engineering by Kathryn A. Ingle)
Advantages of Reverse engineering:
4
Make fist availability of CAD models
4
The physical model is used as the starting point
4
Shortened development process of a product
Developed product at the start of production
Reduce the product and production costs
Powerfid point cloud data collection and management
Flexibility for demanding Rapid Prototyping and Rapid Tooling.
Potential uses of Reverse engineering
The development of CAD models based on physical ones
Editing a C m file using the altered physical model
Creating STL files for use in other Rapid Prototyping techniques
Reverse engineering is the process of analyzing a subject system to create
representations of the system at a higfier level of abstraction. Reverse engineering is a
process that discovers the technological principles of an object or system through
analysis of its structure, function and operation. During complete a reverse engineering
project it often involves mechanical device, electronic component, or a software
program apart and analyzing its fuhctions in detail. Usually, reverse engineering process
is construct a new device or program that does the same thing without actually copying
anything from the original. Reverse engineering is also to bring existing physical
geometry into digital product development environments, to make a digital 3D record
their own products or assess competitors' products. It is used to analyze, for instance,
how a product works, what it does, what components it consists of, estimate costs,
identifj potential patent infringement. Reverse engineering also often is done because
the documentation of a particular device has been lost, and the person who built the
thing is no longer working at the company. Integrated circuits often seem to have been
designed on obsolete, proprietary systems, which means that the only way to incorporate
the functionality into new technology is to reverseengineer the existing product and
then re-design it.
One of the main processes of reverse engineering is the digitizing process. Digitizing
process is done to the reverse engineered part by using the suitable tool depends on the
part. Currently, there is too much high technology tool that had been used in reverse
engineering to measure the physical object by using 3D scanning technologies like
CMMs, laser scanners (figure 2.2a), ATOS, white light digitizers (figure 2.2b) or
computed tomography. The measured data alone, usually represented as a point cloud,
lacks topological information and is therefore often processed and modeled into a more
usable format such as a triangular.
Figure 2.2 (a): 3 0 Laser Scanner
Figure 2.2 (h): White Light Digitizers
ATOS
ATOS (figure 2.2~)is the high-end 3D Digitizer which is flexible optical measuring
machine is based on the principle of triangulation. Projected fringe patterns are observed
with two cameras. 3D coordinates for each camera pixel are calculated with high
precision, a polygon mesh of the object's surface is generated. 3D digitizing with the
mobile ATOS system delivers for all object sizes and complexities with the specialty to:
I.
Highly accurate 3D coordinates
2.
Full-field deviation to CAD
3.
Section based analysis
4.
Complete measuring reports
With the high performance, enormous detail resolution and broad selection of measuring
areas allow for an efficient and precise data gathering and reporting in:
1.
Quality Control
2.
Reverse Engineering
3.
Rapid Prototyping
4.
Rapid hdilling
Figure 2.2 (c): A TOS
2.3
Measuring tools
The digitizing process of reverse engineering must be done with measuring tools and
equipment such as CMM and vernier caliper. This is to validate dimensions obtain from
scannary and to confirm actual size and dimensions. The followings are measuring a tool
that is used in this study.
2.3.1 Coordinate-measuring machine (CMM)
Coordinate-measuring machine (CIWM) is a device for dimensional measuring as shown
in Figure 2.3.1 (a). CMM is a mechatzical system designed to move a measuring probe to
determine h e cootdinates of points on the surface of a work piece. The machines are
available in a wide d g e of sizes and designs with a variety of different probe
technologies. They can be contvolled hnd operated manually, or by CNC or PC controls.
They are offered in various cdtiflguraitions sbch as bench top, ffee-standirig, handheld
and portable. Optical probed aidor lasix ptobes can be used (if pssible in
combination), which change CMM's to measuring microscopes or multi sensor
measuring machines. Fringe projection systems, thodolite triangulation systems or laser
distant and triangulation systems are not called measuring machines, but the measuring
result is the same. Optical probes andlor laser probes can be used (if possible in
combination), which change CMM's to measuring microscopes or multi sensor
measuring machines. Laser probes are used to detect the distance between the surface
and the reference point on the end of the kinematics chain.
First invention of CMM is the UMS 500 (ZeissIGennany) which is had solid
stand with moving table, succeeded by fixed portal (LeitzIGermany). The mechanical
probe will be lead into a touching position, before the position is triggered by switch
(manual) or the probe itself (CNC). The rotary tables of the CMM can be used to
enhance the approachability of complicated work pieces without changing the
mechanical probe.
Mechanical probe is used to detects the point of beginning material viewing from
a chosen direction (-vector), usually perpendicular. Mechanical probes touch the
material with a hard ball located at the end of a shaft at the surface with a distinct force.
In reaction the probe will be deflected and this deflection can be controlled and
measured. The result is the triggering of the "correct" touch point.
This machine is enclosing to software installed in a computer to show the result
of any dimension taken. For each measurement, the set up of the bill of touches (probes)
has been determined first. The problems encountered to get the precise result of
dimension when the probes can be used to measure certain parts of the hand phone
housing especially in the inner side of it. (Coordinate-measuring machine - Wikipedia,
the free encyclopedia.htm). The mechanical of the process is shown in the Figure 2.3.1
(b).
The machine used for this study is Wenzel LH54.
Figure 2.3. I (a): WenzeI LH54
sleeve
p o s b n detector
scale
II
\
'.
damping system
Figure 2.3.1 (b): CMM
They ark &en used for:
d h n s i o n measurement
~
~ r d h l mehurement
e
A&hlarity or orientation measutement
deflhhapping
tiigltizing or imaging
shsk heasurement
2.3.2 Vernier caliper
The Vernier Caliper (Figure 2.3.2) is a precision instrument that can be used to measure
internal and external distances extremely accurately. The example shown below is a
manual caliper. Measurements are interpreted from the scale by the user. This is more
difficult than using a digital vernier caliper which has an LCD digital display on which
the reading appears. The manual version has both an imperial and metric scale.
Manually operated vernier calipers can still be bought and remain popular because they
are much cheaper than the digital version. Also, the digital version requires a small
battery whereas the manual version does not need any power source.
Figure 2.3.2: Mitutoyo Vernier caliper
The Vernier Caliper is used to measure certain part of the product as it can not be define
by using the proper machine as CMM. Vernier caliper is used to measure the inner side
of the part which is can not be measure by using the CMM.
To use a vernier caliper, the error of the equipment must be define first before any
measurement is done to keep the result in proper way and for a digital vernier caliper,
the value must be Omm before any measurement was taken. The equipment also is tested
by using the gauge block to make sure the dimension is correct for certain dimension
taken. The specifications of the vernier caliper are shown in Table 2.3.2 (a).
Table 2.3.2 (a): General specificationfor Mitutoyo Vernier caliper
Mitutoyo
TW
Material
Stainless steel
Measuring range
0" to 8" I Omrn to 200mm
Tolerance
0.02mm
2.4
3D Laser Scanner
A low-powered laser is used to measure the position of a point on an object in 3dimensions. As time progresses, many measurements are taken, building up a complex
and highly accurate 3dimensional map of the surface of the object. To fully record a
complex object the scanner is manually moved around the object to measure points from
many different angles, similar to photographing a stone from different sides to achieve
complete coverage.
2.4.1
Triangulating 3D Laser Scanners
These 3D scanners are so called due to their use of the principle of triangulation. That is,
typically a thin stripe of laser light is projected across the surface of an object and is
viewed by a digital camera. Because the positions of the camera and laser emitter are
fixed and known, it is simple to compute the position of points along the laser stripe in
3dimensions.
Figure 2.4(a) A single detail scan of St. Orland's Stone. The blue line is 12cm long
Triangulating laser scanners have a very high resolution and accuracy making them ideal
for accurately recording fine details on sculptured stonework. In addition, the high
accuracy also enables us to directly measure changes in the surface of the stone either
caused by decay, or perhaps even vandalism. The downside, such as it is, is that
extremely large datasets can be generated.
Time of Flight 3D Laser Scanners
A time-of-flight scanner simply shoots a laser pulse at the object and measures the time
taken for the pulse to return to the scanner. Given that the speed of light is constant, the
distance from the scanner to the surface of the object can be calculated quite easily. The
scanner's motors move the laser emitter backwards and forwards across the object
shooting a laser pulse out at regular time intervals. n e 3dimensional points are
calculated as a combination of the horizontal and vertical angles of the motors plus the
measured dis-ce.
Figure 2.4 (8) Govan cross, GlaSgb*, scdnned with a Callidus time-of-Jlight scanner.
The resolution and a c c h y of time-of-flight scanners is quite limited, typically
operatirig at +I- 6mm accuracy. Time-of-flight scanners cannot be used for recording
fine detail. For accurate tecording, a triangulating scanner should be used. Technology
changes quickly and often, but d high-accuracy and high-resolution system should
always be tised.
2.5
Injection moulding
The Stages of Injection moulding
Stage 1
h u l a t e d or powdered thermoplastic plastic is fed from a hopper into the Injection
Moulding machine. Granules of plastic powder (note the plastics listed above) are
poured or fed intt, a hophr which stores it until it is needed. A heater heats up the tube
and when it reaches a high temperature a screw thread starts turning.
l'he Injection Moulding hachine consists of a hollow steel barrel, containing a rotating
screw (Archemidial Screw). The screw carries the plastic along the barrel to the mould.
Heaters su&ound the barrel melt the plastic as it travels along the barrel. A motor turns a
thread which pushes the granules along the heater section which melts then into a liquid.
Stage 3
The screw is forced to let the melted plastic collects at the end of the barrel.
Once enough plastic has collected a hydraulic r a m pushes the screw forward injecting
the pladii: through a sprue into a mould cavity. The mould is warmed before injecting
and the plastic is injected quickly to prevent it from hardening before the mould is full.
Stage 4
Pressure is maintained for a short time to prevent the material creeping back during
setting (hardening process). This prevents shrinkage and hollows in giving a better
quality product. The moulding is left to cool before removing (ejected) from the mould.
The moulding takes on the shape of the mould cavity as shown in Figure
2.5 .[www. design-technology.orgiinjectionmoulding2.htm]
1 lopper
Mould
Scr&
I lcatcr
'
Ram
1 lydraillic
Fluid
I
I lcatcr
Motor
Figure 2.5: Injection &oirlding machine
bijection moldillg h b two difitent types t h a wete:
1.
b i d runner (two plate and three NAte designs)
2.
hot runner (the more cammon ofthe miherless molds)
I
The diff'ekdfice of both &pes is the jiieseiice of a sprue and miher with evee molded
part in hi doid runnet type. This ektra inolded component must be sepaded fi-oh the
desired molded part.
Cold l7thher holds
Compared to the hot W e r system, the cold runner mold type is very simple and
cheaper. Dtie to its sittiplieity, that is why the mold requires less maintenance and less
skill to set up and operate. Color changes easily since all the plastic in the mold is
ejected with each cycle. So the product will be exchanged easily every time needed. The
two plate and the three plate designs are the two major types of cold runner molds.
Two Plate mold
The first type of cold runner molds is the two plates which is the simplest type of mold.
Two plate molds has one parting line and two sections or halves. The runner system is
be located on this parting line and the part must be gated on its perimeter (see figure 1).
The runner is ejected together with the part for each time operates.
Figure 2.5 (a): Two Plate Mold in Closed (a) and Open (b) Positions
Three Plate mould
Meanwhile, the three plates have two parting lines and three sections involved for each
mould. The runner system can be located on one parting line and the part on the other
parting line. Three plate designs are used because of their flexibility in gating location
which a part can be gated anywhere along its surface. The part must be suitable for edge
gating while a three plate mold design, the parts must be suitable for center gating in the
two plate mold. This will allow for uniform part filling without part-weakening weld
lines. As is the example shown, the optimum gate position at the center of the c u p
shaped product can now be accessed (see figure 2). The runner system can be ejected
separately as the mold opens.
- s t l t 0-w paten
1
Figure 2.5 (b): Three Plate Mold in Closed (a) and Open (b) Positions
Hot Runner Molds
The hot runner mold is a two plate mold with a heated runner system inside one half of
the mold. The runner system through the manifold and the drops conveys the heated
plastic to the part (see figure 3). This system allows greater control over melt
temperatures and other processing conditions. A hot runner system is considered where
production volumes are high and a shorter cycle time is a requirement.
(www.colplas.com~ttips~inj
.shtml)
Figure 2.5 (c) Hot Runner Vertical Mold
20
2.6
Software 3D modelling
The data from CMM started to find its way back into 3D CAD systems. This process led
designers to reverse engineer older designs so that they could use their current 3D CAD
systems to W e r develop the data. The problem is that to accurately define a part,
thousands and sometimes millions of coordinate points are required and this condition is
needed a systems that struggled to handle such large point datasets. Nowadays,
mechanical CAD applications are developing specialized tools to take dense point-cloud
data and thrh it into Class A free-form surfaces. A class surfaces are those aesthetic/ free
form surfaces, which are visible to us (interior/exterior), having an optimal aesthetic
shape and hi& surface quality. Third-party applications are also helping to fill the gap.
The available software that could be used in this study is the SolidWorksO and
CATIAO. SolidWorksO is used ta produce the solid modeling of the hand phone
housing based on the measurement taken. CATIAO is used after that to generate NC
code for machining process of the hand phone housing. The parts created from
SolidWorksO will be transfer to CATIAO and from there, the NC code can be
determined. ~ttp://www.design-engine.com/storiedclas~-surface/clas~h~)
2.6.1
CATIAO
CATIAO is referred to the 3D Product Lifecycle Management software suite and it
supports multiple stages of product development. The stages range from
conceptualization, through design (CAD) and manufacturing (CAM), until analysis
(CAE). CATIAO provides open development architecture through the use of interfaces,
which can be used to customize or develop applications.
2.6.2 SolidWorksO
The SolidWorksO core product includes modeling, assembly, and drawing creation. It
includes tools for 3D modeling, sheetmetal, weldments, and limited freeform surfacing.
It can import numerous file types from other 2D and 3D CAD programs. Also included
is a basic finite element analysis program for design validation called CosmosXpress
and a mold filling program called MoldflowXpress that is related to this study.
SolidWorksO uses a limited "parametric" approach to modeling and assembling. In the
SolidWorksO 3D modeling environment the creation of a solid or surface typically
begins with the definition of topology in either a 2D or 3D sketch. The topology defines
the connectivity and certain geometric relationships between vertices and curves both in
the sketch and external to the sketch. To this topology are added dimensions which
determine the lengths and sizes for the curves and locations for the vertices in
conjunction with topological constraints. The dimensions which are added are termed
"parameters" because they can be changed either independently or by "parameters"
created prior to their creation. The dimensions are limited "parameters" because they
chat be varied by subsequent actions on the sketch in which they are defined. An
e b p l e of
thls lirnikbon is to create a simple rectangle in a 2D sketch, place
dhensions an the sides of the &gle
and then to extrude the 2D sketch to form a
@hdklpibd shape. f i e skktch dimensions cannot be varied based on the 1-tion ( ~ f
tke 2b sketch (kenedtiix)
h e extrusion length. SolidWdrksO would not allow ike
height " p d e t e r " of the rechgle to vary with the s
q
w of tk distance extnided. id
other wdkis the dimellllidh~ot "pzitametkts" cannot be fxiratneterized to "paiameteh"
cr&d
in ihe s(lbse#ellt hikfrirdky of feattlres. Ptidrieters are the~fbrefixed in thk
~ t i i t ehat contains them. solid*orkso is
t h e t e ~ e hietiiciiid
:
1H the cteatid of
features in kat subsequeht features should have rio e k m on prior features. To ctezite
v o l d d and modificatiolls, soliddrorks~e d i o y s ti feature-based system that can be
rolled back to previous states in case something must be changed or multiple
configurations of the same part nitst be handled. To assemble components, mates are
created, which define the relative positions of the components to each other.
Methodology is defined as a body of rnahods, dies, ahd postulates employed by
a discipliiik*a particUar firdced~reot set of b ~ e d t i r e and
s the &zilysis df the ptihciples
or ptodures bf in@@ in a piuficulat fieid. The common idea of methodology is the
collection, the cornparatitre study, &id the critiqlte df the idividual methods that are
used ifi a
discipline or field of ifiquiry. h-lethdol6gy refers to more ththan a simple
set of thethods. This is. wh). scholarly h t e ~ t u r eoften includes a section on the
methodoioa of the researchers.
.
This chapter shows the process of reverse engineering being applied. The
processes of the reverse efigirieedng begin by measuring the hand phone housing by
using the etjtiipments. ?%en, by using related software such as SolidWorksO an exact
duplicate based on the measurements can be produced. The process of reverse
engineering of the mold is done then by taking the original parts as reference.
3.2
The Process Flow of Methodology
Identifying
the product
(Hand
Phone
housing)
Select suitable
Produce 3D
Measuring
material
model
by
the product
specification for
using 3D
(CMM,
-+
the actual
-+ scanner and +
vernier
product and
Solidworks
caliper)
0
run analysis
i
1
+
Design the
core and
cavity for
the part of
the band
phone
1
Produce the
Prototype
using the
c
rapid
prototyping
machine
J
+
i
Picture 3.2: The methodology process flow
3.2.1
Identifying the product
Figure 3.2.1 (a) :Nokia 6680
24
Redesign hand
phone housing
based on the
safety factor
h