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B. Suryatal et al.
The photopolymer used in this experimentation was polyethylene glycol diacrylate and 2% Irgacure 784 as a photoinitiator was added in the photopolymer.
The maximum absorbance of the photopolymer was in the range of 315–340 nm.
The stepper motor was used to rotate the ball screw which moves the Z-stage
platform up and down. The sliced layer image was focused on platform through
projector and objective lens. The sliced image consists of black and white portion;
the photopolymer on the platform with white portion of the focused image was solidified. The Creo 3.0 software was used for modelling of 3D CAD model. A special
MATLAB code was developed for slicing of the 3D CAD model and this sliced
3D CAD model was imported into the Creation Workshop software which was
used to control the focusing time period of sliced images through DLP projector.
The Creation Workshop software also controls the motion of the Z-stage through
Arduino MEGA 2560 microcontroller and NEMA 17 bipolar stepper motor. Finally,
the different shape objects are built by curing the aforementioned photocurable resin.
The digital microscope was used to measure the dimensions of the built parts. The
overall cost of the developed SLA is two lac thirty five thousand Indian Rupees only.
2.2 Slicing of 3D CAD Model
The 3D CAD model of the object which was to be built by using STL process was
developed with the help of CREO 3.0 software and then it was saved in .STL file
format. The .STL file consists of an unordered list of triangular facets that represent
the outside skin of a part. The triangular facets are described by a unit normal vector
and a set of X, Y, and Z coordinates for each of the three vertices. The unit vectors
indicate the outside of the part. Since the STL model consists of triangular facets,
it is an approximate model of the accurate CAD data. .STL file is a simple solution
for representing 3D CAD data and it provides small and accurate files for data
transfer for specific shapes [8]. After generating the .STL file of the 3D CAD model,
then it was sliced into a number horizontal cross-sections with the help of specially
developed MATLAB code by using ray tracing method [9]. The sliced CAD model
in MATLAB window is shown in Fig. 2. The sliced CAD model was imported in
Creation Workshop software and the sliced layers were focused one by one at required
time interval with the help of DLP projector through objective lens on the Z-stage
platform and finally, the 3D object was built.
B. Suryatal et al.
The photopolymer used in this experimentation was polyethylene glycol diacrylate and 2% Irgacure 784 as a photoinitiator was added in the photopolymer.
The maximum absorbance of the photopolymer was in the range of 315–340 nm.
The stepper motor was used to rotate the ball screw which moves the Z-stage
platform up and down. The sliced layer image was focused on platform through
projector and objective lens. The sliced image consists of black and white portion;
the photopolymer on the platform with white portion of the focused image was solidified. The Creo 3.0 software was used for modelling of 3D CAD model. A special
MATLAB code was developed for slicing of the 3D CAD model and this sliced
3D CAD model was imported into the Creation Workshop software which was
used to control the focusing time period of sliced images through DLP projector.
The Creation Workshop software also controls the motion of the Z-stage through
Arduino MEGA 2560 microcontroller and NEMA 17 bipolar stepper motor. Finally,
the different shape objects are built by curing the aforementioned photocurable resin.
The digital microscope was used to measure the dimensions of the built parts. The
overall cost of the developed SLA is two lac thirty five thousand Indian Rupees only.
2.2 Slicing of 3D CAD Model
The 3D CAD model of the object which was to be built by using STL process was
developed with the help of CREO 3.0 software and then it was saved in .STL file
format. The .STL file consists of an unordered list of triangular facets that represent
the outside skin of a part. The triangular facets are described by a unit normal vector
and a set of X, Y, and Z coordinates for each of the three vertices. The unit vectors
indicate the outside of the part. Since the STL model consists of triangular facets,
it is an approximate model of the accurate CAD data. .STL file is a simple solution
for representing 3D CAD data and it provides small and accurate files for data
transfer for specific shapes [8]. After generating the .STL file of the 3D CAD model,
then it was sliced into a number horizontal cross-sections with the help of specially
developed MATLAB code by using ray tracing method [9]. The sliced CAD model
in MATLAB window is shown in Fig. 2. The sliced CAD model was imported in
Creation Workshop software and the sliced layers were focused one by one at required
time interval with the help of DLP projector through objective lens on the Z-stage
platform and finally, the 3D object was built.