Robot Mechanisms and Mechanical Devices Illustrated - Profe Saul
Robot Mechanisms and Mechanical Devices Illustrated - Profe Saul
Robot Mechanisms and Mechanical Devices Illustrated - Profe Saul
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Introduction<br />
xix<br />
Figure 2 Solid Ground Curing (SGC): First, a photomask is generated on a glass plate by<br />
a xerographic process. Liquid photopolymer is applied to the work platform to form a<br />
layer, <strong>and</strong> the platform is moved under the photomask <strong>and</strong> a strong UV source that<br />
defines <strong>and</strong> hardens the layer. The platform then moves to a station for excess polymer<br />
removal before wax is applied over the hardened layer to fill in margins <strong>and</strong> spaces. After<br />
the wax is cooled, excess polymer <strong>and</strong> wax are milled off to form the first “slice.” The first<br />
photomask is erased, <strong>and</strong> a second mask is formed on the same glass plate. Masking <strong>and</strong><br />
layer formation are repeated with the platform being lowered <strong>and</strong> moved back <strong>and</strong> forth<br />
under the stations until the 3D model is complete. The wax is then removed by heating<br />
or immersion in a hot water bath to release the prototype.<br />
The photomask is then moved to the exposure station, where it is aligned<br />
over a work platform <strong>and</strong> under a collimated UV lamp.<br />
Model building begins when the work platform is moved to the right<br />
to a resin application station where a thin layer of photopolymer resin is<br />
applied to the top surface of the work platform <strong>and</strong> wiped to the desired<br />
thickness. The platform is then moved left to the exposure station, where<br />
the UV lamp is then turned on <strong>and</strong> a shutter is opened for a few seconds<br />
to expose the resin layer to the mask pattern. Because the UV light is so<br />
intense, the layer is fully cured <strong>and</strong> no secondary curing is needed.<br />
The platform is then moved back to the right to the wiper station,<br />
where all of resin that was not exposed to UV is removed <strong>and</strong> discarded.<br />
The platform then moves right again to the wax application station,<br />
where melted wax is applied <strong>and</strong> spread into the cavities left by the<br />
removal of the uncured resin. The wax is hardened at the next station by<br />
pressing it against a cooling plate. After that, the platform is moved right<br />
again to the milling station, where the resin <strong>and</strong> wax layer are milled to a<br />
precise thickness. The platform piece is then returned to the resin application<br />
station, where it is lowered a depth equal to the thickness of the<br />
next layer <strong>and</strong> more resin is applied.
Change language