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Appendix
Get help for the optional libraries that are available in the Extension Manager.
Multibody Processing Library
The Multibody Processing library supports multibody-related, multi-disciplinary workflows and system-level vibration analysis in time and frequency domains.
frfplot
Plot MotionSolve Frequency Response Functions (FRFs) computed from XML and related A,B,C,D state matrices.

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Appendix
Get help for the optional libraries that are available in the Extension Manager.
- Multibody Processing Library
  The Multibody Processing library supports multibody-related, multi-disciplinary workflows and system-level vibration analysis in time and frequency domains.
  - cpsdplot
    Plot MotionSolve Frequency Response Functions (FRFs) estimated from output/input signals cpsd versus input signals pwelch.
  - dsacpsdplot
    Plot MotionSolve Dynamic Signal Analysis (DSA) result component in time and frequency domain.
  - dsafftplot
    Plot MotionSolve Frequency Response Functions (FRFs) computed from MotionSolve XML and related A, B, C, D state matrices.
  - dsafrfplot
    Plot MotionSolve Dynamic Signal Analysis (DSA) using Frequency Response Functions (FRFs) computed from the MotionSolve XML and related A, B, C, D state matrices.
  - fftplot
    Plot MotionSolve Fast Fourier Transforms (FFTs) computed from output signals.
  - frfplot
    Plot MotionSolve Frequency Response Functions (FRFs) computed from XML and related A,B,C,D state matrices.
  - mbcrossvalue
    Extract value crossing data that is used to detect time of events in order to compute some response over a reduced time domain by leveraging the corresponding index range.
  - mbindexatvalue
    Extract value crossing data, used to detect the index of the time of events in order to compute some response over a reduced time domain by leveraging the corresponding index range.
  - mbipsd
    Compute Inverse Power Spectral Density (PSD) that is used to define an excitation time domain signal from a PSD profile.
  - pulley
    Define a pulley component to parametrize the definition of a cable system.
  - tangent
    Define a tangent line to parametrize the definition of a cable system.
  - winch
    Define a winch component to parametrize the definition of a cable system.
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frfplot

Plot MotionSolve Frequency Response Functions (FRFs) computed from XML and related A,B,C,D state matrices.

Attention: Valid only with Altair Product Integration Extension

Syntax

frfplot()

frfplot(xml)

frfplot(xml,few)

frfplot(xml,few,red)

Inputs

xml: XML file names (without extension).; Type: char; Dimension: cell
few: Frequency exponent window in a 2-element vector form.; Type: double; Dimension: vector
red: Reduction option (not supported yet). Default: 0 (no reduction).; Type: double; Dimension: scalar

Examples

Example with results from a landing gear model.

fftplot({'./LandingGear_Retracted/ldg_retracted';'./LandingGear_Deployed/ldg_deployed'},'Expressions','dxyz',{'DXleft';'DYleft';'DZleft'},[0.2,10],[0.5,2.5]);

Comments

This function creates a comparison plot of MotionView results in frequency domain by computing FRF between multiple plant outputs and plant inputs (leveraging A,B,C,D state matrices output).