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1. Definir requerimientos

2. Crear / escoger el concepto

3. Generar el diseo

4. Analizar el sistema

5. Fabricar prototipos

6. Probar los prototipos

7. Aceptar el diseo final

Optimizacin del diseo

CAE

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Prototipos con sistema directo

CAD2D -> CAD 3D -> STL-> PROCESO_RP ->PROTOTIPO

CAD 3D

facet normal -4.470293E-02 7.003503E-01 -7.123981E-01

outer loop

vertex -2.812284E+00 2.298693E+01 0.000000E+00

vertex -2.812284E+00 2.296699E+01 -1.960784E-02

vertex -3.124760E+00 2.296699E+01 0.000000E+00

endloop

endfacet

Modelo 3D

SOLIDS

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WHAT ABOUT THE PRICE?

IT DEPENS ON THE DIMENSIONS (HEIGTH, VOLUME..)

IT GOES FROM $100USD UP TO 10,000 USD

TO ORDER AND BUY A PROTOYIYPE IT IS VERY IMPORTANT TO

UNDERSTAND THE APPLICATIONA AND USE, BASED ON THAT,

THE PROCESS NEEDS TO BE SELECTED.

Product Review, assembly , operation, etc...

http://www.cc.utah.edu/~asn8200/rapid.html#COMM

THE RAPID PROTOTYPING HOME PAGE

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MANUFACTURING OF RAPID PROTOTYPES, BACKGROUND.

The goal of rapid mechanical prototyping (RP) is to be able to quickly fabricate complex-

shaped, three-dimensional parts directly from CAD models.

One approach for accomplishing this is to use solid freeform fabrication (SFF) processes. SFF

methodologies have the following attributes:

they can build arbitrarily complex 3D geometries

the process planning is automatic, based on a CAD model

they use a generic fabrication machine, i.e., do not require part-specific fixturing or

tooling

they require minimal or no human intervention to operate

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Fig. 4 SFF enabling technologies

Practical implementations of layered manufacturing for modern

manufacturing needs have been made possible by several enabling

technologies as in to novel arrangements (Fig. 4).

Traditional

Technologies

Powder Metallurgy

Welding

Extrusion CNC machining

Litography

Enabling Component

Technologies

Lasers

Ink-jet printers

Motion control

CAD

Solidsmodeling

SFF

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Current SFF systems are based upon a layered manufacturing approach (Fig. 1). In this

method, a solid 3D CAD model of the object is first decomposed into cross-sectional layer

representations in the process planner.

The planner then generates trajectories for guiding material additive processes to physically

build up these layers in an automated fabrication machine to form the object. Sacrificial

supporting layers are also simultaneously built up to fixture the object. For example, shapes

are first decomposed into 2-dimensional layers, i.e., layers that can be represented by a

planar cross-section with an associated uniform thickness.

Fig. 1 Solid freeform fabrication using a layered manufacturing approach

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Each physical layer, which consists of the cross-section and a complementary shaped

sacrificial layer, is then deposited and fused to the previous layer (Fig. 2a) using one of

several available deposition and fusion technologies.

The sacrificial material has two primary roles: first, it holds the part, analogous to afixture in traditional fabrication techniques; second, it serves as a substrate upon which

unconnected regions and overhanging features can be deposited.

The unconnected regions require this support since they are not joined with the main

body until subsequent layers are deposited. Another use of sacrificial material is to form

blind cavities in the part.

Fig. 2 Generic fixturing

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Other building approaches use support structures only where required, i.e., for the

unconnected regions and steep overhanging features (Fig. 2b).

These explicit support structures are deposited with the same material as the object beingformed, but are drawn out in a semisolid fashion so that they are easy to remove once the

part is completed. For example, they may be deposited as thin wall structures.

SFF can rapidly and automatically be planned and executed, independent of part shape, for

several reasons:

(1) the shape decomposition operation maps complex 3D geometry into simple 2D

representations,

(2) custom fixturing is not required, and

(3) the machinery to implement these systems is relatively easy to operate.

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Simulacin de maquinado

http://localhost/var/www/apps/conversion/tmp/scratch_1/Videos/Ejemplo%20Turbina%20BobCAD-CAM%20-%20YouTube.wmvhttp://localhost/var/www/apps/conversion/tmp/scratch_1/Videos/Ejemplo%20Turbina%20BobCAD-CAM%20-%20YouTube.flvhttp://localhost/var/www/apps/conversion/tmp/scratch_1/Videos/Ejemplo%20Turbina%20BobCAD-CAM%20-%20YouTube.wmvhttp://localhost/var/www/apps/conversion/tmp/scratch_1/Videos/Ejemplo%20Turbina%20BobCAD-CAM%20-%20YouTube.flv

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Non SFF RP Process

Machining plays an important role in rapid prototyping.

CNC machining, however, is not generally considered to be an SFF methodology, not only

because it requires skillful human intervention to help plan the operations and to operate

the equipment, but also because machining often requires custom fixturing and has

inherent geometric imitations.