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400 Chapter 5: Creating Geometry
Force—
Specifies the amount of force exerted
between the two bound objects. Positive values
pushtheobjectsapart,whilenegativevaluespull
them together.
•
Force is meas ured i n— Lets you specify the
measurement of force to use: Pounds per inch
or Newtons per meter.
Spring Dynamics Object
Create panel > Geometry > Dynamics Objects > Object
Type rollout > Spring button
Create menu > D ynamics > Spring
TheSpringobjectisadynamicsobjectintheshape
of a coiled spring that lets you simulate a flexible
spring in dy namics simulations. You c an specif y
the over all diameter and length of t he spring , the
number of turns, and the diameter and shape of its
“wire.” When used in a dynamics simulation, the
compression and extension pressure of the spring
are calculated as well.
Pr ocedur es
To create a spring:
1.
Drag and release to specify the outside
diameter.
2. Move the mouse and click to specify the overall
length of the spring.
To use a spring in a dy namics s imulation:
Thefollowingmustbeinplacetousethespring
forces in a dynamics simulation:
1. Bind two objects to the ends of the spring, and
chooseBoundtoObjectPivotsintheEndPoint
Method group box at the top of the command
panel.
2. In the dynamics simulation, add the spring
to the Object List. (The spri ng itself is not
adjustable in the dynamics Edit Object dialog,
so all of the dynamics parameters wil l be
disabled for the spring object.)
3. Includeatleastoneoftheboundobjectsor
aparentof one of the bound objects in the
simulation. For example, you can bind the
ends of a spring to two dummy objects, and
oneofthedummiescanbethechildofan
object that’s included in the simulation. The
dummy without a parent will be stationary and
the spring will p ass its force through the other
dummy to its parent.
Note: Spring is an "ideal" object w ith no mass.
While it can be used in dynamics simulations,
it cannot participate directly in collisions or
effects. A spring can only exert force on other
objectsinsimulations.Asaresult,whenyou
assignaspringobjecttoadynamicssimulation,
and t hen view it in the Edit Object dialog, all of
the parameter settings are disabled.
Interfa ce
Spring Parameters rollout