07-04-2011, 12:21 PM
Rapid%20Prototyping[1].ppt (Size: 345.5 KB / Downloads: 414)
Introduction
• Rapid Prototyping (RP) techniques are methods that allow designers to produce physical prototypes quickly.
• It consists of various manufacturing processes by which a solid physical model of part is made directly from 3D CAD model data without any special tooling.
• The first commercial rapid prototyping process was brought on the market in 1987.
• Nowadays, more than 30 different processes (not all commercialized) with high accuracy and a large choice of materials exist.
• These processes are classified in different ways: by materials used, by energy used, by lighting of photopolymers, or by typical application range
The Rapid Prototyping Technique
• In the Rapid Prototyping process the 3D CAD data is sliced into thin cross sectional planes by a computer.
• The cross sections are sent from the computer to the rapid prototyping machine which build the part layer by layer.
• The first layer geometry is defined by the shape of the first cross sectional plane generated by the computer.
• It is bonded to a starting base and additional layers are bonded on the top of the first shaped according to their respective cross sectional planes.
• This process is repeated until the prototype is complete.
Prototyping- What is it ?
Physical Model of the product
. Degrees of Prototyping
. Full Complete scale Model - functional model
. Scaled Model - functional/ simulated material
. Geometrical configuration
. Partial ….
Prototyping- Why?
Visualization
Design Change (iterations)
Free Form Prototyping (complex object fabrication/ visualization)
Testing Fit/ Packaging
Cost, Time, and resource estimation
Process Planning
First to Market -- Critical for today’s industry
Rapid production (concurrent activities)
JIT concept (0 Inventory)
Rapid tooling / no tooling -- trend in technology
Design verification
Design for manufacturability
Design for assembly
Design for maintainability
Design for reliability
Design for Quality
Design Parameters (Tolerances/ allowances)
Concurrent Engineering
Tooling
. Reverse Engineering
. Die fabrication
. Tool Path generation
Limited Production
Classification of Prototyping Technology
Subtractive Processes (Material Removal)
Ex : Milling, turning, grinding,-- machining centers .., when used for prototype production
Degree of automation vary
Additive (Material Build-up)
Ex : Stereolithography
Degree of sophistication vary
Formative (Sculpture)
Ex : Forging, Casting, ..
When used for Prototyping, it is usually manual
Sophistication of Prototyping Technology
Such Technology is known by different terms, such as :
Desktop Manufacturing
Rapid Prototyping
Tool-less Manufacturing
3-D printing
Free form Fabrication (F3)