OPTIMIZING THE DESIGN OF THE PART |
The part we have designed can be optimized, thus achieving a more efficient product. Given that the part will rotate clockwise, reshaping the upper part of the teeth could reduce the weight of the part as well as increase its resistance. We could also modify the profile of the hole in order to increase resistance in zones under axle pressure.
To carry out these optimizations, we will use new tools such as NURBS lines. The final steps in this process will be generating a mesh and visualizing the changes made relative to the previous design.
This example begins with a file named "optimizacion.gid".
- Choose Open
from the Files
menu and open the file "optimizacion.gid".
- The file contents appear on the screen. In order to work more comfortably, select Zoom In,
thus magnifying the image. This option is located both in the GiD Toolbox and in the mouse menu under Zoom
.
Figure 39. Contens of optimizacion.gid
|
|
- Make sure that the "aux" layer is activated.
- Choose Geometry->Edit->Divide->Lines->Num Divisions
.This option divides a line into a specified number of segments.
- A window comes up in which to enter the number of partitions. Enter 8.
- Select the line segment from the upper part of a tooth (Figure 39) and press ESC
.
- Using the option Geometry->Create->Point
, and create a point with the coordinates (40, 8.5).
- Choose Geometry->Create->NURBS line
to create a NURBS curve. The NURBS line to be created will pass through the two first points which have been created on dividing the line at point (40, 8.5) and by the two last points of the divided line.
Figure 40. Optimizing the design
|
|
- Select the first point through which the curve will pass. To do this use Join Ctrl-a
, located in Contextual
in the mouse menu.
- One at a time, select the rest of the points except the last one. Use Join Ctrl-a
each time in order to ensure that the line passes through the point.
- Before selecting the last point, choose Last Point
in the Contextual
menu. Then finish the NURBS line. The result is shown in Figure 40.
- Send the new profile (See Figure 41) to the "profile" layer and eliminate the auxiliary lines.
Figure 41. Optimizing the design
|
|
- Repeat the process explained in sections 2.11 and 2.12 to create the wheel surface: use the rotation tool to create the entire profile and, using Geometry->Create->NURBS Surface->By contour
, select it to create a NURBS surface.
- Repeat the processes explained in section 3 (except section 3.1) and sections 4.1 and 4.2 to create the prismatic volume.
Modifying the profile of the hole |
- Move the lines of the octagon placed in the profile surface to the “profile” layer (with the Send To
button).
- Click Off
the "prism" layer. Hiding it simplifies the space on the screen.
- Choose Geometry->Create->Object->Circle
.
- Enter (-10.5, 0) as the center point. Enter a normal to the XY
plane (Positive Z) and a radius of 1.5.
- From the Toolbox, use the Delete->Surfaces
tool to delete the surface of the circle so that only the line is left. This way the Geometry->Edit-> Intersection->Multiple Lines
option may be used to intersect the circle (circumference). Select only the circle and the two straight lines that intersect it.
- Choose Copy
from the Utilities
menu and make seven copies (Multiple copies
=7), rotating the circle -45 degrees.
- Using the intersection options, delete the auxiliary lines leaving only the valid lines, thus obtaining the new profile of the hole. The result is illustrated in Figure 42.
- Create the hole in the surface of the wheel using Geometry->Edit->Hole NURBS Surface
(the result is shown in Figure 43).
Figure 42. The new hole profile
|
|
|
Figure 43. The surface of the new optimized design
|
|
|
Creating the volume of the new design |
Repeat the same process as in section 4.3:
- In the Copy
window, choose Translation
and Surfaces
. Enter two points that define a translation of 10 units, for example (0, 0, 10) and (0, 0, 0). (Make sure that the Multiple Copies value is 1).
- Choose Do Extrude Volume
in the Copy
window.
- Click Select
and select the surface of the wheel. Press ESC
.
Figure 44. The volume of the optimized design
|
|
- Click On
the "prism" layer.