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INTERNATIONAL JOURNAL OF PROFESSIONAL ENGINEERING STUDIES Volume 10 /Issue 1 / MAY 2018
IJPRES
SPUR GEAR DEVELOPMENT USING RAPID PROTOTYPING BY REVERSE ENGINEERING 1 SAMBASIVARAO, 2 Mr. SHAIK RAFI
1 UG Scholar, Dept of MECH, NALANDA INSTITUTE OF TECHNOLOGY, Village: KANTEPUDI,
SATTENAPALLI(M), GUNTUR(Dist), A.P, India, Pin: 522438.
Email id: [email protected] 2 Assistant professor, Dept of MECH, NALANDA INSTITUTE OF TECHNOLOGY, Village: KANTEPUDI,
SATTENAPALLI(M), GUNTUR(Dist), A.P, India, Pin: 522438.
ABSTRACT
This project is about application of reverse
engineering. Reverse engineering helps in obtaining
the geometry of part or product which is not available
otherwise. Its application makes it possible to
reconstruct the original component with its drawing
and manufacturing process. In this project we are
going to produce spur gear used in automobile by
Reverse Engineering. The procedure includes various
stages which will help understand the different
phases of reverse engineering.
The process starts with understanding the reverse
engineering procedure. The part geometry is first
obtained with the help of scanning technology. Then
with the use of different softwares, the three-
dimensional model of the spur gear is obtained. Once
the CAD model is obtained the part is analyzed using
SOLIDWORKS simulation tool. After the optimized
geometry is obtained, the pattern of the part is
obtained using Rapid prototyping machine. This can
be used for casting of the original part.
INTRODUCTION
In today’s intensely competitive global market,
product enterprises are constantly seeking new ways
to shorten lead times for new product developments
that meet all customer expectations. In general,
product enterprise has invested in CAD/CAM, rapid
prototyping, and a range of new technologies that
provide business benefits. Reverse engineering (RE)
is now considered one of the technologies that
provide business benefits in shortening the product
development cycle. Figure 1.1 below depicts how RE
allows the possibilities of closing the loop between
what is “as designed” and what is “actually
manufactured”.
What Is Reverse Engineering?
Engineering is the process of designing, , assembling,
manufacturing and maintaining products and
systems. There are two types of engineering, forward
engineering and reverse engineering. Forward
engineering is the traditional process of moving from
high-level abstractions and logical designs to the
physical implementation of a system. In some
situations, there may be a physical part/ product
without any technical details, such as drawings, bills-
of-material, or without engineering data. The process
of duplicating an existing part, subassembly, or
product, without drawings, documentation, or a
computer model is known as reverse engineering.
Reverse engineering is also defined as the process of
obtaining a geometric CAD model from 3-D points
acquired by scanning/ digitizing existing
parts/products.
Fig.1: Product development life cycle
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The process of digitally capturing the physical
entities of a component, referred to as reverse
engineering (RE), is often defined by researchers
with respect to their specific task (Motavalli &
Shamsaasef 1996). Abella et al. (1994) described RE
as, “the basic concept of producing a part based on an
original or physical model without the use of an
engineering drawing”. Yau et al.(1993) define RE, as
the “process of retrieving new geometry from a
manufactured part by digitizing and modifying an
existing CAD model”. Reverse engineering is now
widely used in numerous applications, such as
manufacturing, industrial design, and jewelry design
and reproduction For example, when a new car is
launched on the market, competing manufacturers
may buy one and disassemble it to learn how it was
built and how it works. In software engineering, good
source code is often a variation of other good source
code. In some situations, such as automotive styling,
designers give shape to their ideas by using clay,
plaster, wood, or foam rubber, but a CAD model is
needed to manufacture the part. As products become
more organic in shape, designing in CAD becomes
more challenging and there is no guarantee that the
CAD representation will replicate the sculpted model
exactly.
Fig.2: Physical-to-digital process
REVERSE ENGINEERING –THE GENERIC
PROCESS:
The generic process of reverse engineering is a three-
phase process as depicted in Figure.
Fig.3: Reverse engineering- the generic process
SCANNING:
This phase is involved with the scanning strategy–
selecting the correct scanning technique, preparing
the part to be scanned, and performing the actual
scanning to capture information that describes all
geometric features of the part such as steps, slots,
pockets, and holes. There are two distinct types of
scanners, contact and noncontact.
A. Contact Scanners
These devices employ contact probes that
automatically follow the contours of a physical
surface .In the current market place, contact probe.
Fig.4: Contact scanning touch probe.
Scanning devices are based on CMM technologies,
with a tolerance range of +0.01 to 0.02 mm.
However, depending on the size of the part scanned,
contact methods can be slow because each point is
generated sequentially at the tip of the probe.
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B. Noncontact Scanners
A variety of noncontact scanning technologies
available on the market capture data with no physical
part contact. Noncontact devices use lasers, optics,
and charge-coupled device (CCD) sensors to capture
point data, as shown in Figure. Although these
devices capture large amounts of data in a relatively
short space of time, there are a number of issues
related to this scanning technology.
• The typical tolerance of noncontact scanning is
within ±0.025 to 0.2 mm.
• Some noncontact systems have problems generating
data describing surfaces, which are parallel to the
axis of the laser.
Fig.5: Optical scanning device. Originally published
in Rapid Prototyping Casebook, McDonald, J.A.
Fig.6: Vertical faces–touch probe versus a laser.
POINT PROCESSING
This phase involves importing the point cloud data,
reducing the noise in the data collected, and reducing
the number of points. These tasks are performed
using a range of predefined filters. It is extremely
important that the users have very good
understanding of the filter algorithms so that they
know which filter is the most appropriate for each
task.
This phase also allows us to merge multiple scan data
sets. Sometimes, it is necessary to take multiple scans
of the part to ensure that all required features have
been scanned. This involves rotating the part; hence
each scan datum becomes very crucial. Multiple scan
planning has direct impact on the point processing
phase.
APPLICATION GEOMETRIC MODEL
DEVELOPMENT
In the same way that developments in rapid
prototyping and tooling technologies are helping to
shorten dramatically the time taken to generate
physical representations from CAD models, current
RE technologies are helping to reduce the time to
create electronic CAD models from existing physical
representations. The need to generate CAD
information from physical components will arise
frequently throughout any product introduction
process. The generation of CAD models from point
data is probably the most complex activity within RE
because potent surface fitting algorithms are required
to generate surfaces that accurately represent the
three-dimensional information described within the
point cloud data sets. Most CAD systems are not
designed to display and process large amounts of
point data; as a result new RE modules or discrete
software packages are generally needed for point
processing.
INTRODUCTION TO POWER
TRANSMISSION
Power transmission states that speed and torque
conversions from rotating power source to other
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device. Here in our project we design and analysis
the intermediate shaft for stress and deflection, it is
necessary to know the applied forces. If the forces are
transmitted through gears, it is necessary to know the
gear specifications in order to determine the forces
that will be transmitted to the shaft. But stock gears
come with certain bore sizes, requiring knowledge of
the necessary shaft diameter. This project will focus
on an overview of a power transmission system
design, demonstrating how to incorporate the details
of each component into an overall design process.
Fig.7: Compound reverted gear train.
Transmission
The term power transmission is defined as the
movement of energy from a source to an output
device that performs work. In mechanical power
transmissions, a device is interposed between a
source of power and a specific application for the
purpose of adapting one to the other. Most
mechanical transmissions function as rotary speed
changers; the ratio of the output speed to the input
speed may be constant (as in a gearbox) or variable.
On variable-speed transmissions the speeds may be
variable in discrete steps or they may be continuously
variable within a range.
The need for a transmission in an automobile is a
consequence of the characteristics of the internal
combustion engine. Engines typically operate over a
range of 600 to about 7000revolutions per minute
(though this varies, and is typically less for diesel
engines), while the car's wheels rotate between 0 rpm
and around 1800 rpm.
TYPES OF POWER TRANSMISSION
SYSTEMS
Manual transmission
Manual transmissions come in two basic types:
A simple but rugged sliding-mesh or
unsynchronized/non-synchronous system,
where straight-cut spur gear sets spin freely,
and must be synchronized by the operator
matching engine revs to road speed, to avoid
noisy and damaging clashing of the gears.
The now common constant-mesh gearboxes,
which can include non-synchronized, or
synchronized/synchromesh systems, where
typically diagonal cut helical (or sometimes
either straight-cut, or double-helical) gear sets
are constantly "meshed" together, and a dog
clutch is used for changing gears. On
synchromesh boxes, friction cones or "synchro-
rings" are used in addition to the dog clutch to
closely match the rotational speeds of the two
sides of the (declutched) transmission before
making a full mechanical engagement.
Semi-automatic
A hybrid form of transmission where the integrated
control system handles manipulation of the clutch
automatically, but the driver can still - and may be
required to - take manual control of gear selection.
This is sometimes called a "clutchless manual," or
"automated manual" transmission. Many of these
transmissions allow the driver to fully delegate gear
shifting choice to the control system, which then
effectively acts as if it was a regular automatic
transmission. They are generally designed using
manual transmission "internals", and when used in
passenger cars, have synchromesh operated helical
constant mesh gear sets.
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Early semi-automatic systems used a variety of
mechanical and hydraulic systems - including
centrifugal clutches, torque converters, electro-
mechanical (and even electrostatic) and
servo/solenoid controlled clutches - and control
schemes – automatic declutching when moving the
gearstick, pre-selector controls, centrifugal clutches
with drum-sequential shift requiring the driver to lift
the throttle for a successful shift, etc. -and some were
little more than regular lock-up torque converter
automatics with manual gear selection.
Automatic
These primarily use hydraulics to select gears,
depending on pressure exerted by fluid within the
transmission assembly. Rather than using a clutch to
engage the transmission, a fluid flywheel, or torque
converter is placed in between the engine and
transmission. It is possible for the driver to control
the number of gears in use or select reverse, though
precise control of which gear is in use may or may
not be possible.
Automatic transmissions are easy to use. However, in
the past, automatic transmissions of this type have
had a number of problems; they were complex and
expensive, sometimes had reliability problems
(which sometimes caused more expenses in repair),
have often been less fuel-efficient than their manual
counterparts (due to "slippage" in the torque
converter), and their shift time was slower than a
manual making them uncompetitive for racing. With
the advancement of modern automatic transmissions
this has changed.
Fig.8: Epicyclic gear train
POWER TRANSMISSION DEVICES
Gear Drive
Chain drive
Belt Drive
GEAR TRAINS
A gear train is formed by mounting gears on a frame
so that the teeth of the gears engage. Gear teeth are
designed to ensure the pitch circles of engaging gears
roll on each other without slipping; this provides a
smooth transmission of rotation from one gear to the
next.
Gears trains are classified into following types Simple gear train Compound gear train Reverted compound gear train Planetary gear train
GEARS
Gear is a part, as a disk, wheel, or section of a shaft,
having cut teeth of such form, size and spacing that
they mesh with teeth in another part to transmit or
receive force and motion.
They can be applied between two shafts which are
Parallel Collinear Perpendicular and intersecting Perpendicular and nonintersecting Inclined at any arbitrary angle
METHODOLOGY USED FOR CASE STUDY OF GEAR A case study of Gear is done for the purpose of
obtaining point cloud data which was exported into
associate nursing .stl format of the CAD program.
The best method to approximate a 3D geometrical
model is by approximating it with lots of triangular
aspects.
A. The typical reverse engineering process can be
summarized in following steps:
1. Physical model which needs to be redesigned or to
be used as the base for new product.
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2. Scanning the physical model to get the point
cloud. The scanning can be done using various
scanners available in the market.
3. Processing the points cloud includes merging of
points cloud if the part is scanned in several settings.
The outlines and noise is eliminated. If too many
points are collected then sampling of the points
should be possible.
4. To create the polygon model and prepare .stl files
for rapid prototyping.
5. To prepare the surface model to be sent to
CAD/CAM packages for analysis.
6. Tool path generation with CAM package for
suitable CNC machine manufacturing of final part on
the CNC machine.
Fig.9: Front view of Gear which has to be produced
Fig.10: Side view of Gear which has to be produced
Fig.11: Back view of Gear which has to be produced
Fig.12: Isometric view of Gear which has to be
produced
The Gear has been scanned in a Roland Model lpx-
600 laser scanner .
Fig.13: Roland Model LPX-600 Laser Scanner
The Roland Model lpx-600 laser scanner is a medium
sized scanner used to scan object of maximum height
of around 150 mm and diameter of 120 mm. It
operates with interface of computer with software Dr.
Picza which helps in setting up the scanning
parameters and also shows the scanning process. It
stores the scanned file in .stl format
Once the scanned image of object is obtained using
scanner it is exported into .stl format shown in fig..
The parameter set in the above software decides the
quality of scanned image. As the time for scanning
increases the quality of scanned image improves.
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Fig.14: .stl Image File of Scanned Component
B. Obtaining the solid geometry from the point cloud data The original .stl data is scattered and contains some
noise around the boundary of model. The noise
creates a problem while generating a solid model so it
has to be cleaned from the data. Solid works software
has Scan to 3D option which help to point out the
noise from the data and with the help of noise
reduction tool the noise is reduced. Then we get a
clean .stl data which can be used for further
processing.
INTRODUCTION TO SOLID WORKS
Solid works mechanical design automation software
is a feature-based, parametric solid modeling design
tool which advantage of the easy to learn windows TM
graphical user interface. We can create fully associate
3-D solid models with or without while utilizing
automatic or user defined relations to capture design
intent.
Building a model in Solid Works usually starts with a
2D sketch (although 3D sketches are available
for power users). The sketch consists of geometry
such as points, lines, arcs, conics (except the
hyperbola), and spines. Dimensions are added to the
sketch to define the size and location of the
geometry. Relations are used to define attributes such
as tangency, parallelism, perpendicularity, and
concentricity. The parametric nature of Solid Works
means that the dimensions and relations drive the
geometry, not the other way around. The dimensions
in the sketch can be controlled independently, or by
relationships to other parameters inside or outside of
the sketch.
SOLIDWORKS SCAN TO 3D
Using the Solid Works software’s ScanTo3D
functionality, you can open scan data from any
scanner (mesh or point cloud files) or curve data from
mathematics software, prepare the data, then convert
it into a surface or solid model.
ScanTo3D significantly reduces the time required to
build complex 3D models from non-digital data.
Designers can use ScanTo3D for various purposes:
Medical designers - Create anatomical objects
for reference.
Fig.15: Example of a solid created from scanned data of a hand, using the Surface
Wizard's Automatic creation.
Consumer product designers - Create quick
representations of physical components made
from clay, foam, etc.
Machine designers - Create quick references to
OEM parts.
Two Methods for Converting Scan Data to a
Solid Model.
Semi-manual Creation: Direct Mesh Referencing
Direct mesh referencing is useful for very complex surfaces, such as consumer products.
Semi-automated Creation Using Wizards
The Mesh Prep and Surface Wizards guide you
through the ScanTo3D process
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MESH PREPARATION WIZARD
Mesh Prep Wizard - Welcome Property Manager
The Mesh Prep Wizard prepares and cleans up mesh or point cloud files. The wizard produces a mesh feature from which you can create surfaces and a solid model using direct mesh referencing or the Surface Wizard.
Orientation Property Manager
Align the mesh or point cloud feature to the global
origin and planes, which is important for accurate
downstream manipulation of the model.
Noise Removal Property Manager
For point cloud data, this tool divides the cloud into
partitions and removes points that are outside the
average distribution, resulting in the removal of noise
points.
Removing Noise From Point Clouds or Meshes
You can remove noise using the Noise Removal
Property Manager. Noise is defined as either points
that are outside the average distribution, or separate
mesh patches that are small in area.
Extraneous Data Removal Property Manager
Extraneous data typically exists in point cloud data
and comes from the fixture used to hold the part in
place while you scan it. Choose a tool to select
extraneous data, then click Delete to remove the data.
Mesh Boundaries
Mesh boundaries form along boundary edges.
ScanTo3D can create boundary curves only along
boundary edges. Boundary edges are commonly
found on meshes that represent surfaces or have large
holes in them.
SURFACE WIZARD CREATION MANAGER
Surface Wizard - Welcome Property Manager
The Surface Wizard converts a mesh feature into
surfaces and a solid model.
Solid/Surface Creation Property Manager
The Surface Wizard can automatically create surfaces
or guide you to create surfaces.
Automatic Creation
Automatically create solids based on the desired
amount of detail.
SURFACE EXTRACTION PROPERTY
MANAGER
Use this Property Manager to extract sub-meshes
from the model as surfaces. You later can convert the
surfaces into solids using the Solid Works surface
tools such as Trim, Knit, and Thicken. To manually
extract surfaces, select a sub-mesh, then select a
surface type under Face Settings.
Fig.16: Model before surface extraction Model after
extracting two cylindrical and two b-spline surfaces
When you extract surfaces, you might see salient sub-
meshes (arrows), which are transitions between
primary mesh regions. Transition regions usually
show a large variation in geometry, such as
curvature. You usually do not convert salient sub-
meshes as surfaces during guided surface creation,
but instead you create these surfaces later in Solid
Works.
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Fig.17: Extracted surfaces using ScanTo3D
Fig.18: Solid model created from the extracted
surfaces using Untrim, Trim, Extend,Knit,
and Thicken tools.
Exporting files:
After you import a mesh or cloud point file into a
Solid Works document using ScanTo3D, We export
the document as another file type that contains the
mesh or cloud point data.
1. Click File > Save As.
2. Select a file format in Save as type:
ScanTo3D (*.xyz)
ScanTo3D (*.wrl).
ScanTo3D (*.stl).
ScanTo3D (*.3ds)
ScanTo3D (*.iges)
The scanned file is imported in solid works software
which helps to extract geometry from the .stl file or
point cloud data shown in figure below to Solid
geometry.
Fig.19: .Stl file imported to solid works Scan to 3D
By using Mesh preparation wizard meshing of the
.Stl file is done.
Increasing the global smoothness then entering into
surface wizard manager for adjusting surface
resolution.
Fig.20: surface failure areas
Fig.21: individual sub meshes are identified
Now all the surface are extracted as shown below
Fig.22: surfaces extraction
Fig.23: model is completed with extra surfaces
Finally the base model is complete by using Trim,
knit ,fillets and chamfer options for generating solid
model. The file is saved in .STL format.
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Fig.24: Four views of the Gear
The drawings are generated for the Gear model and
the following dimensions are obtained.
Symbol Parameter Gear
m Module 1.79~2mm
b Face width 8.5mm
T No. of teeth 29
D Pitch circle
diameter
52mm
Profile 20° full depth involute
INTRODUCTION TO SOLIDWORKS
SIMULATION:
Solid Works® Simulation is a design analysis system
fully integrated with Solid Works. Solid Works
Simulation provides simulation solutions for linear
and nonlinear static, frequency, buckling, thermal,
fatigue, pressure vessel, drop test, linear and
nonlinear dynamic, and optimization analyses.
Powered by fast and accurate solvers, Solid Works
Simulation enables you to solve large problems
intuitively while you design. Solid Works Simulation
comes in two bundles: Solid Works Simulation
Professional and Solid Works Simulation Premium to
satisfy your analysis needs. Solid Works Simulation
shortens time to market by saving time and effort in
searching for the optimum design.
Fig.25: Simulation example
ANALYSIS STEPS :
The steps needed to perform an analysis depend on
the study type. You complete a study by performing
the following steps:
Create a study defining its analysis type and
options.
If needed, define parameters of your study. A
parameter can be a model dimension, material
property, force value, or any other input.
Define material properties.
Specify restraints and loads.
The program automatically creates a mixed
mesh when different geometries (solid, shell,
structural members etc.) exist in the model.
Define component contact and contact sets.
Mesh the model to divide the model into many
small pieces called elements. Fatigue and
optimization studies use the meshes in
referenced studies.
Run the study.
View results.
STRUCTURAL ANALYSIS OF GEAR USING
SOLIDWORKS SIMULATION TOOL
Structural analysis procedure:- The Structural
analysis involves the following
procedure:
- Pre-Processing: It include the description of the
geometry or model, the physical characteristics of the
model.
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Definition of type of analysis, material properties,
Loads and boundary conditions
- Solution: it involves the application of the finite
element analysis
- Run analysis to obtain solution (stresses).
- Post-Processing: It includes the visualization and
interpretation of the results of the solution.
PERFORMING STATIC ANALYSIS ON GEAR
The structural stress analysis of the gear tooth model
is carry out using the FEA in
Solid works simulation .The load applied at the
tooth of the gear by applying the analysis over the
tooth which is facing the load we get the stress
distribution in the numeric as well as in the form of
the color scheme.
Material Properties Alloy steel
Density = 7700 kg/m^3
Poison ratio = 0.28
Young' modulus = 2.1E+11 N/mm^2
Fixed:
Force: 500N
Mesh Information
Mesh type Solid Mesh Mesher Used: Standard mesh
Automatic Transition: Off Include Mesh Auto
Loops: Off
Jacobian points 4 Points Element Size 2.7397 mm
Tolerance 0.136985 mm Mesh Quality High
MESH INFORMATION - DETAILS
Total nodes = 27167
Total elements = 16148
STUDY RESULTS FOR FACE WIDTH 8.5 MM
Stress
Strain
Displacement
STUDY RESULTS FOR FACE WIDTH 10.5 MM
Stress
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Strain
Displacement
STUDY RESULTS FOR FACE WIDTH 12.5MM
Stress
Strain
Displacement
STUDY RESULTS FOR FACE WIDTH 14.5MM
Stress
Strain
Displacement
RESULTS AND DISCUSSIONS
The structural stress analysis of the gear tooth model
is carry out using the FEA in Solid works simulation.
The load applied at the tooth of the gear .by applying
the analysis over the tooth which is facing the load
we get the stress distribution in the numeric as well
as in the form of the color scheme. By varying the
face width and keeping the other parameters constant
various models of the gear are created. For
determining at any stage during the design of the gear
face width is an important parameter. The results of
the variation in face width from (8.5 mm to 14.5mm
)there is continuous decrement in the value of the
stress of the tooth of the gear stress. Results of
theoretical and static analysis are closer, therefore
the design are accepted. As it is seen clearly from all
tables and graphs the maximum bending stress values
are increase with the decrease of face width. In this
work we got on two results as follow
_ Theoretical results (from Lewis equation directly)
_ static analysis results
And all results are closer as shown in graphs.
Effect of face width :
The effect face width on maximum bending stress is
study by varying the face width for five values which
are (b=8.5mm, 10.5mm, 12.5mm, 14.5mm) the
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magnitude of the stresses obtained for those face
widths are displayed .
COMPARISION OF THEORETICAL STRESS
VALUES AND SOLIDWORKS VALUES
Face width
(mm)
Bending
stresses (MPa)
Lewis equation
Bending
stresses (MPa)
Static analysis
8.5 50.7 47.2
10.5 41.04 40.2
12.5 34.4 29.2
14.5 29.7 25.2
Table.1: Comparison of bending stresses
(theoretical and software )
Introduction to rapid prototyping
rapid prototyping (rp) can be defined as a group of
techniques used to quickly fabricate a scale model of
a part or assembly using three-dimensional computer
aided design (cad) data. what is commonly
considered to be the first rp technique, stereo-
lithography, was developed by 3d systems of
valencia, ca, usa. the company was founded in 1986,
and since then, a number of different rp techniques
have become available.
why rapid prototyping ?
the reasons of rapid prototyping are
• to increase effective communication.
• to decrease development time.
• to decrease costly mistakes.
• to minimize sustaining engineering changes
• to extend product lifetime by adding
necessary features and eliminating redundant
features early in the design.
rapid prototyping decreases development time by
allowing corrections to a product to be made early in
the process. by giving engineering, manufacturing,
marketing, and purchasing a look at the product early
in the design process, mistakes can be corrected and
changes can be made while they are still inexpensive.
the trends in manufacturing industries continue to
emphasize the following:
• Increasing number of variants of products.
• Increasing product complexity.
•Decreasing product lifetime before
obsolescence.
• Decreasing delivery time.
METHODOLOGY OF RAPID PROTOTYPING
The basic methodology for all current rapid
prototyping techniques can be summarized as
follows:
1. A CAD model is constructed, and then
converted to STL format. The resolution can be
set to minimize stair stepping.
2. The RP machine processes the .STL file by
creating sliced layers of the model.
3. The first layer of the physical model is created.
The model is then lowered by the thickness of
the next layer, and the process is repeated until
completion of the model.
4. The model and any supports are removed. The
surface of the model is then finished and
cleaned
PROTOTYPING OF THE GEAR USING
SELECTIVE LASER SINTERING
RAPIDPROTOYPING SYSTEM
FORMIGA P 100 - small, fast, efficient, e-
Manufacturing in the Compact Class Plastic laser-
sintering system for the direct manufacture of series,
spare parts and functional prototypes.
Fig:26: RP Systems
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TECHNICAL SPECIFICATIONS
TABLE NO – 1:
Effective building
volume
200 mm x 250 mm x 330
mm (7.9 x 9.8 x 13 in)
Building speed
(material-dependent)
up to 24 mm height/h (0.94
in/h)
Layer thickness
(material-dependent) typically 0.1 mm (0.004 in)
Support structure not necessary
Laser type CO2, 30W
Precision optics F-theta lens
Scan speed during
build process up to 5 m/s (16.4 ft/sec)
Power supply 16 A
Power consumption
(nominal) 2 Kw
Nitrogen generator integrated (optional)
Compressed air
supply
minimum 6,000 hPa; 10
m3/h (87 psi; 13.08 yd3/h)
TABLE NO – 2:
Machine with
powder
containers and
touch screen
1,320 mm x 1,067 mm x 2,204
mm
(51.97 x 42.01 x 86.77 in)
Recommended
installation space
3.2 m x 3.5 m x 3 m (126 x 137.8
x 118.1 in)
Weight Ca. 600 kg (1,323 lb)
Powder mixing
station
700 mm x 500 mm x 1,000 mm
(27.56 x 19.69 x 39.37 in)
Unpacking and
sieving station
1,200 mm x 700 mm x 1,500 mm
(47.24 x 27.56 x 59.06 in)
TABLE NO – 3:
PC current Windows operating system
Software EOS RP Tools; Magics RP
(Materialise)
CAD
interface
STL. Optional: converter to all
common formats
Network Ethernet
Certification CE
CONCLUSIONS
In theory of Gear, we are considering that the load
is acting at one point and the stress is calculated.
The calculation of maximum stresses in a gear at
tooth root is three dimensional problems. The
accurate evaluation of stress state is complex task.
The contribution of this thesis work can be
summarized as follows:
The strength of gear tooth is a crucial parameter to
prevent failure. In this work, it is shown that the
effective method to estimate the root bending stress
using three dimensional model of a gear and to
verify the accuracy of this method the results with
different face width of teeth are compared with
theoretical values.
The face width is an important geometrical
parameter in design of gear as it is expected in this
work the maximum bending stress decreases with
increasing face width.
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