T-FLEX Parametric CAD. Fundamentals. 2D Design

Fundamentals. Two-Dimensional Design
Example: Disassembling a Pyramid
676
Another example of animation is the animation of taking
apart a toy pyramid. The 3D model of the pyramid is
located in the library “Documentation samples”,
the folder “\2D Design\Animation\Pyramid”.
The model of the pyramid is made of a base with a pole,
stacked up four rings, and a topping. When
disassembling, the base stays still, while the rings and
the topping are “undone” one by one from the base and
put around.
To achieve this, the shifts from the axes for the
respective 3D operations are defined by variable-based
parameters. The variables Z_1, Z_2, Z_3, Z_4, Z_5 will
define the shifts along the Z-axis, corresponding to the
vertical movement of the rings (along the axis of the
pole). The variables XY_1, XY_2, XY_3, XY_4 and
XY_5 describe the movement of the rings and the
topping in the horizontal plane along the X- and Y-axes
(removal of the rings off the base).
Such a large number of varied variables require use of
the “Animation Screenplay” application.
Let's define the diagrams for the model variables varying
with time in the animation screenplay. Two diagrams
correspond to each body being moved (for the topping,
those are the diagrams of the variables Z_5 and XY_5,
for the blue ring – the diagrams Z_4 and XY_4, etc.).
One of those defines the object moving in the vertical
plane, the other one - in the horizontal. The diagrams are
designed in such a way, that each ring first moves up
along the pole (the values of the respective variable Z in
the diagram increase). At reaching the top of the pole
(the flat portion of the Z variable diagram), a ring starts
moving in the horizontal plane at some distance from the
base (the growing portion of the respective variable XY
diagram), and then goes down (the descending portion of
the Z variable diagram). The rings start moving
sequentially with the time delay interval of T=2.
Once all diagrams are created, let's define the animation parameters: the interval T from 0 to 25 (the last ring
finishes its movement at the time instant T=23), and the step equal to 0.25.
Upon starting the animation, the process of taking the pyramid apart will be simulated on the screen. The
pictures below show certain animation stages corresponding to the time instants shown on the diagrams.