You will create three parts representing the packaging, the
circuit board, and the floor.
The chips will be represented using discrete point masses. You
will also create a number of datum points to aid in positioning the part
instances and the point masses.
The packaging is a three-dimensional solid structure. Create a
three-dimensional, deformable part with an extruded solid base feature to
represent the packaging; name the part
Packaging. Use an approximate part size of
0.1, and sketch a 0.02 m × 0.024 m rectangle as
the profile. Specify 0.11 m as the extrusion
depth.
From the main menu bar, select
ShapeCutExtrude
to create the cut in the packaging in which the circuit board will rest.
Select the left end of the packaging as the plane for the extruded
cut. Select a vertical line on the packaging profile to be vertical and on the
right in the sketching plane.
In the Sketcher, use the vertical construction line tool
to create a vertical construction line through the center of
the packaging. Apply a fixed constraint to the construction line.
Sketch the profile of the cut shown in
Figure 1.
Use a Symmetry constraint to center the cut about the
construction line and edit the dimensions of the cut profile so that it is
0.002 m wide and extends a distance of 0.012 m into the packaging.
Figure 1. Profile of cut in packaging (with grid spacing
doubled).
In the Edit Cut Extrusion dialog box that
appears upon completion of the sketch, select Through All
as the end condition and select the arrow direction representing a cut into the
packaging.
Create a datum point centered on the bottom face of the cut, as shown
in
Figure 2.
This point will be used to position the board relative to the packaging.
Figure 2. Datum point at center of cut in packaging.
From the main menu bar, select
ToolsDatum.
The Create Datum dialog box appears.
Accept the default selection of Point as the
datum type and select Midway between 2 points as the
method.
Select the two points centered on the bottom face at either end of
the cut to be the two points between which the datum point will be created.
Abaqus/CAE
creates the datum point shown in
Figure 2.
Define the circuit board geometry
The circuit board can be modeled as a thin, flat plate with chips
attached to it. Create a three-dimensional, deformable planar shell to
represent the circuit board; name the part
Board. Use an approximate part size of
0.5, and sketch a 0.100 m × 0.150 m rectangle
for the profile.
Create the three datum points shown in
Figure 3.
These points will be used to position the chips on the board.
Figure 3. Datum points used to position the chips relative to the board.
Numbers in parentheses are (x, y) coordinates in
meters based on a local origin at the bottom left corner of the circuit
board.
From the main menu bar, select
ToolsDatum.
The Create Datum dialog box appears.
Accept the default selection of Point as the
datum type, and select Offset from point as the method.
Select the bottom left corner of the board as the point from which
to offset, and enter the coordinates for one of the points shown in
Figure 3.
Repeat Step c to create the other two datum points.
Define the floor
The surface that the circuit board will impact is effectively rigid.
Create a three-dimensional, discrete rigid planar shell to represent the floor;
name the part Floor. Use an approximate part
size of 0.5. The rigid surface should be large
enough to keep any deformable bodies from falling off the edges.
Sketch a 0.2 m × 0.2 m square as the profile. To simplify the
positioning of parts in the assembly of the model, ensure that the center of
the surface corresponds to point (0, 0) in the sketcher. This also corresponds
to the origin of the global coordinate system.
Assign a reference point at the center of the part.
to create a vertical construction line through the center of
the packaging. Apply a fixed constraint to the construction line.
