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This task will show you how to define the restraint
excitation set in a:
Defining a restraint excitation set allows you to define an
imposed motion of the support in the frequency domain or in the time
domain. |
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Only available with the Generative Dynamic
Response Analysis (GDY) product. |
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Harmonic Dynamic Response Case
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Open the
sample57_1.CATAnalysis document from the samples directory.
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Double-click the restraint excitation object belonging to
the harmonic dynamic response case.
In this particular case, double-click Restraint
Excitation.1. under the Harmonic Dynamic Response Case
set.
The Restraint Excitation Set dialog box appears.
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- Name: gives the name of the restraint excitation
set. If needed, you can modify it.
- Axis System:
- Type:
- Global: if you select the Global Axis system,
the components field will be interpreted as relative to the
fixed global rectangular coordinate system.
- User: if you select a user-defined axis system,
the components will be interpreted as relative to the specified
rectangular coordinate system.
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- Current axis: lets you select the desired
axis system.
- Local orientation: (Cartesian)
the components are interpreted as relative to a fixed
rectangular coordinate system aligned with the Cartesian
coordinate directions of the User-defined Axis.
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- Selection:
- Selected modulation: lets you select a white noise
modulation or a frequency modulation.
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You cannot select a time modulation in a
harmonic dynamic response analysis case. |
- Selected acceleration: lets you select the
acceleration that will be modulated.
- Selected phase: lets you specify the phase value.
- Degrees of freedom: gives you the list of the
degrees of freedom, the associated modulation, acceleration and
phase (T for translation and R for Rotation)
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Set the desired parameters in the Restraint Excitation
Set dialog box.
In this particular example:
- Select the Global option as Axis System Type.
- Select Frequency Modulation.1 as Selected
modulation.
- Enter 1m_s2 as Selected acceleration.
- Enter 1deg as Selected phase.
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Press Enter to update the Restraint Excitation
Set dialog box.
The TX degree of freedom is defined and
the Restraint Excitation Set dialog box appears as shown below:
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You can define other degrees of freedom.
To do this: |
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Select an other degree of freedom.
In this particular example, select the RY
degree of freedom. |
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Set the different parameters (associated modulation,
acceleration and phase).
In this particular example:
- Select the White Noise.1 modulation as Selected
modulation.
- Enter 3rad_s2 as Selected acceleration.
- Enter 2deg as Selected phase.
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Press Enter to update the Restraint Excitation
Set dialog box.
The RY degree of freedom is defined and
the Restraint Excitation Set dialog box appears as shown below:
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Click OK.
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Transient Dynamic Response Case
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Open the
sample57_1.CATAnalysis document from the samples directory.
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Double-click the restraint excitation belonging to a
transient dynamic response case.
In this particular case, double-click Restraint
Excitation.1.
The Restraint Excitation Set dialog box appears.
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- Name: gives the name of the restraint excitation
set. If needed, you can modify it.
- Axis System:
- Type:
- Global: if you select the Global Axis system,
the components field will be interpreted as relative to the
fixed global rectangular coordinate system.
- User: if you select a User-defined Axis system,
the components will be interpreted as relative to the specified
rectangular coordinate system.
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- Current axis: lets you select the desired
axis system
- Local orientation: (Cartesian)
the components are interpreted as relative to a fixed
rectangular coordinate system aligned with the Cartesian
coordinate directions of the User-defined Axis.
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- Selection:
- Selected modulation: lets you select a time
modulation.
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You cannot select a frequency modulation. |
- Selected acceleration: lets you select the
acceleration that will be modulated.
- Degrees of freedom: gives you the list of the
degrees of freedom, the associated modulation, acceleration (T
for translation)
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Set the desired parameters in the Restraint Excitation
Set dialog box.
In this particular example:
- Select the Global option as Axis System Type.
- Select Time Modulation.1 as Selected modulation.
- Enter 1m_s2 as Selected acceleration.
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Press Enter to update the Restraint Excitation
Set dialog box.
The Restraint Excitation Set dialog box appears as
shown below:
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You can define other degrees of freedom.
To do this: |
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Select an other degree of freedom.
In this particular example, select the TY
degree of freedom. |
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Set the different parameters (associated modulation and
acceleration).
In this particular example:
- Select the White Noise.1 modulation as Selected
modulation.
- Enter 3rad_s2 as Selected acceleration.
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Press Enter to update the Restraint Excitation
Set dialog box.
The TY degree of freedom is defined and
the Restraint Excitation Set dialog box appears as shown below:
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Click OK.
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