FrequencyInputs

Defines excitation inputs to a Frequency Response Analysis.

Inputs to a frequency response analysis are provided in frequency form characterized by amplitude and phase angle. The input is applied on a body and can be of the type - Displacement, Velocity, Acceleration or Force.

Create/Edit FrequencyInputs

To create a FrequencyInput:

From the Model Browser, select the system to which the entity is to be added.
From the Model ribbon, References group, click the FrequencyInputs icon .
A guide bar to create/edit FrequencyInputs appears.
Resolve the Body on which the input is applied by clicking on a body graphic in the modeling window or by using the Advanced selector .
Resolve the Origin (location where the input is applied) using one of the following methods:
1. Pick an existing point in the modeling window.
2. Hover and click on a CADGraphic location (an edge corner, center, or surface center). A new Point will be created at this location.
3. Use the Alt key to highlight the mesh of a CADGraphic or FileGraphic. Hover and click on a node. A new Point will be created at this location.
4. Use the Advanced selector to pick an existing point.
Resolve the Reference Marker, the coordinate frame along which the input is applied by clicking on a marker in the modeling window or by using the Advanced selector .
Click the Play button or the Create button in the modeling window to create the entity.
The entity is in edit mode once it is created and its microdialog with properties appears on the modeling window near the location of the entity.

To edit a FrequencyInput:

FrequencyInput can be edited in two ways.

Using the guide bar and microdialog:
1. Select the FrequencyInput to be edited and click on the FrequencyInputs icon in the Model ribbon. The FrequencyInput tool is in edit mode with the guide bar and microdialog visible.
2. To change the Body references and Origin, activate the collector in the guide bar and pick from the modeling window or use the Advanced selector.
3. FrequencyInput Type, Amplitude and Phase Angle can be changed in microdialog. Select the required FrequencyInput type under the FrequencyInput Type option.
  Note: Amplitude and Phase Angle cannot be set to values other than Linear using the microdialog.
Tip: To select a different FrequencyInput entity to edit while in the edit context, click on the Select Existing FrequencyInput to edit icon at the left of the guide bar.

Using the Entity Editor:

Select the FrequencyInput either in the Model Browser or the modeling window. Its properties are listed in the Entity Editor for edits.

Table 1. FrequencyInput Properties
Property	Description
General
Label	Descriptive label for the entity.
Varname	Variable name of the entity.
ID	Integer identifier.
Active	Active state of the entity. True or False. Entity is deactivated if False.
Body	Body on which frequency input is applied.
Origin	Point location at which frequency input is applied.
Reference Marker	Coordinate reference frame about which the frequency input is applied as listed in the DOFs (see below).
Properties
Type	Type of input. Available choices are Displacement, Velocity, Acceleration, or Force.
Amplitude Type	Select the type of amplitude input: Linear – to input a constant amplitude value. Curve – to provide amplitude as a curve input. Spline3D – to provide amplitude as a Spline3D input. Expression – to provide amplitude as a solver expression.
Value (amplitude)	Amplitude of the frequency input when Amplitude Type is set to Linear.
curve (amplitude)	When Amplitude Type is Curve, select the curve entity that describes the amplitude as a variation with frequency.
Interpolation	Select the interpolation scheme for the curve or Spline3D – AKIMA, CUBIC, LINEAR or QUINTIC.
Independent variable	Enter a solver expression as the independent variable for the curve.
Spline3D (amplitude)	When Amplitude Type is Spline3D, select the Spline3D entity that describes the amplitude as a variation with frequency and another independent variable.
Independent variable X	When Amplitude Type is Spline3D, enter a solver expression as the first independent variable for the spline3D entity.
Independent variable Z	When Amplitude Type is Spline3D, enter a solver expression as the second independent variable for the spline3D entity.
Expression (amplitude)	When Amplitude Type is Expression, enter a solver expression that describes the variation of the amplitude as function of frequency.
Phase Angle Type	Select the type of phase angle input: Linear – to input a constant phase angle value. Curve – to provide phase angle as a curve input. Spline3D – to provide phase angle as a Spline3D input. Expression – to provide amplitude as a solver expression.
Value (phase_angle)	Phase angle of the frequency input when Amplitude Type is Linear.
curve (phase_angle)	When Phase angle Type is Curve, select the curve entity that describes the phase angle as a variation with frequency.
Interpolation	Select the interpolation scheme for the curve or Spline3D – AKIMA, CUBIC, LINEAR or QUINTIC.
Independent variable	Enter a solver expression as the independent variable for the curve.
Spline3D (phase_angle)	When Phase angle Type is Spline3D, select the Spline3D entity that describes the phase angle as a variation with frequency and another independent variable.
Independent variable X	When Phase angle Type is Spline3D, enter a solver expression as the first independent variable for the spline3D entity.
Independent variable Z	When Phase angle Type is Spline3D, enter a solver expression as the second independent variable for the spline3D entity.
Expression (phase_angle)	When Phase angle Type is Expression, enter a solver expression that describes the variation of the phase angle as function of frequency.
DOFs	Indicate direction of application of the frequency input in the Reference marker coordinate frame.
Appearance
Visible	Controls the display of the entity in the modeling window.
Note and Tags
Note	Optional descriptive note.
Attachment Candidates	Add tags for the entity to use as possible attachments to Systems/Assemblies/Analyses.

Comment:

Amplitude values should be in the selected solver units.
Phase angle should be in radians.