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John James Marshall thesis.pdf - OpenAIR @ RGU - Robert Gordon ...

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Selective Laser Sintering (SLS®) 134 is an additive rapid prototyping (RP)<br />

technology. Nylon or metal powder is applied in fine layers and sintered<br />

in a series of 2D sections by a CO 2 laser into a solid mass defined from a<br />

3D digital description of the part.<br />

Laminated Object Manufacturing (LOM) 135 is a fabrication process that<br />

uses a laser to cut successive cross-sections of an object from layers of<br />

paper applied from a roller with an adhesive coating on the backside.<br />

The laser cuts the outline of the cross-sections that form the object. Once<br />

the laser has cut the object it proceeds to create hatch marks that<br />

surround the object with squares that can be removed as cubes once the<br />

entire object has been laminated and cut. When all the cubes have been<br />

removed, the part is sanded down and a lacquer is used to seal it. The<br />

finished part has a surface and density similar to wood.<br />

Fused Deposition Modeling (FDM) 136 is a rapid prototyping (RP)<br />

technology. A plastic filament is heated to melt the material and can then<br />

be extruded through a numerically controlled nozzle.<br />

3D printing 137 is a category of rapid prototyping (RP) technology. These<br />

are various methods of converting a digital 3D model into a physical<br />

object. The 3D printer spreads out a thin layer of material (for example<br />

gypsum powder or molten wax). Between layers the build piston drops<br />

down, making room for the next layer. This process is repeated and each<br />

successive layer is bonded to the next layer from the print head.<br />

3D Scanning allows for the digital replication of real world objects. Utilising the<br />

latest motion control and handheld laser scanners virtual models can be created<br />

in 3D from a real world object or environment. A 3D scanner is a device that<br />

analyses a real-world object or environment to collect data on its shape. This<br />

usually creates a point cloud which is used to reconstruct the surface of the<br />

134 http://www.3dsystems.com/products/sls/index.asp<br />

135 http://www.cubictechnologies.com/Prototyping/INDEX.HTM<br />

136 http://intl.stratasys.com/index.html<br />

137 e.g. http://www.3dsystems.com/products/multijet/index.asp, http://www.2objet.com/, http://www.solid-scape.com/<br />

and http://www.zcorp.com/home.asp<br />

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