VibraTools Suite™ Data Sheet

Overview

The VibraTools Suite™ of toolboxes for MATLAB turns MATLAB into a state-of-the-art analysis system for noise and vibration analysis, acoustics, structural dynamics, and environmental engineering (durability) analysis. With the toolboxes you get functionality, for example, for spectrum analysis, RPM analysis, modal analysis, and durability analysis. Each toolbox provides a comprehensive set of high-level commands that makes it easy to perform the most advanced tasks. In addition, the toolboxes include a number of examples that illustrate how to perform tasks ranging from statistics and spectrum analysis to more advanced tasks such as modal analysis parameter estimation, and generation of vibration test spectra from operating data.

Using MATLAB for analysis of noise and vibration signals simplifies traceability issues, since the analysis procedures are easily documented through the scripts. In addition the open scripts of the toolboxes make it easy to see the details of the analysis, which is necessary for good documentation. The ability to modify the built-in scripts also ensures a completely open software environment without limits. With the toolboxes in your hand you will find yourself in a learning experience, where you will gradually understand more of the details behind advanced noise and vibration analysis.

Requirements

VibraTools requires

MATLAB 5.1 or higher from The MathWorks Inc.
Signal Processing Toolbox from The MathWorks Inc.

ModalTools and/or DuraTools additionally require VibraTools.

Overview

VibraTools is the basic toolbox and is a prerequisite for the add-on toolboxes, ModalTools and DuraTools. It includes commands for import/export of data, a structured data format for storing vibration data including header information of measurement points and directions etc. VibraTools provides state-of-the art functionality for filtering, integration/ differentiation of signals, spectrum analysis, statistics for data quality assurance, analysis of rotating machines etc.

Specifications:

Data Import	Universal File 58 format (all functions); Time data from: SONY PCscan formats I, II, and III, TEAC, nSoft, HP Standard Data Format (SDF), Dactron text and .sig files, TRAS, WAV format. Data are stored in a Structured Data Format, see below.
Structured Data Format	Multichannel data format for storage of time data, spectra, etc., including: function identifier, sampling frequency, input/output point and direction, input/output units, free text lines, X-, Y-, Z-axis labels, auxiliary custom fields. Extensive commands to extract information from headers to MATLAB variables and vice versa, including a search function.
Correlation Analysis	Normalized Autocorrelation, Normalized Cross Correlation.
Frequency Analysis	Linear (RMS) spectra with Uniform, Hanning and Flattop windows; Power Spectral Density (PSD) with Hanning window; Transient Spectrum with and without phase; Octave and Third octave analysis with digital filters; PSD to third octave conversion.
Time Windows	Hanning, , Hanning with 1 Hz noise bandwidth, Flattop according to ISO 18431-1.
Time Data Processing	State-of-the-art integration and differentiation by digital filtering; Conversion of acceleration to velocity by RC filter (compatible with analog integration); A-, C- weighting by digital filters; Comfort filters according to ISO 2631 and ISO 8041 standards; Running RMS values with linear and exponential averaging; Octave- and Third octave filters.
Frequency Weighting	A-, C-weighting of linear and quadratic spectra; Frequency Domain integration and differentiation.
2D Graphing	Simplified commands for: scanning data files; Min/max display for compression of large amounts of data for display; dB conversions; Text in plots; Text from structured header in plots; Octave and third octave spectrum plots with and without total level; A4 Portrait/Landscape printing.
3D Graphing	Simplified commands for plotting of: Time spectral maps, RPM spectral maps, Third octave contour, maximum velocity, and max RMS maps; Waterfall maps.
Graphical User Interface (GUI)	Simplified GUI commands for standardized window definitions with: buttons, radio buttons, sliders, checkboxes, text, popup menus.
Statistics	Scaled amplitude probability density; Normal probability density function; Statistical functions: crest factor, skewness, kurtosis, maximax, irregularity factor; Frame statistics; Quality assurance with direct reporting; Stationarity tests: static and as function of time; A/D conversion test; Expected number of zero crossings, zero detection of "dead" signal.
RPM Analysis	Extract RPM-time function from tacho signal; Tacho smoothing; RPM Spectral map with fixed sampling frequency: Hanning and Flattop window; Order tracks from RPM Spectral map with and without frequency band summation; Synchronous resampling; Order map; Order tracks from Order map with and without order band summation.
Auxiliary Functions	Clip signal on positive/negative side; Half sine pulse; cosine pre/post taper signal.
Time Data processing	Whole body vibration with shock according to ISO 2631-5.
RPM Analysis	Order tracking with complex orders (with phase); Vold-Kalman filters order tracking filters for single or crossing orders; Time data extraction using Vold-Kalman filters.
Data Acuistion	Menu based data acquisition using the soundcard; Signal generator capable outputting sine, noise or square signals.
Binary File Format Conversion	IEEE floating point conversion; IEEE floating point conversion (exponent first); IEEE double precision floating point conversion; Long/short integer format conversion; Hewlett-Packard floating point conversion.

Overview

ModalTools is an add-on toolbox for experimental modal analysis and simulation of dynamic mechanical systems. It contains functions for modal parameter extraction (curve-fitting) compatible with other modal analysis software. But it also provides functionality for simulation of mechanical systems. Thus there are functions for computing time domain forced response of linear systems based on either a modal model with poles and residues (mode shapes) which can be obtained experimentally or analytically, or from knowledge of the mass, damping, and stiffness matrices of a model. In addition to the above, ModalTools contains functions for principal component analysis for noise source identification etc., and functions for estimation of multiple-input-multiple-output frequency responses from time data. Included are also functions for conditioned signals, especially useful for identification of nonlinear systems.

Specifications:

Data Import/Export

Universal File format 15 (geometry), 55 (shapes) and 82 (trace lines/connectivity)

Animation of Modes

Geometry definition; Easy-to-use animation of mode shapes; AVI file generation from animation; Static mode shape plots.

Synthesize FRFs

Synthesize frequency response functions (FRFs) from M, C, K matrices; Synthesize FRFs from M, K systems with modal damping; Synthesize FRFs from poles and residues (mode shapes).

Convert FRFs

Convert FRFs between acceleration/velocity/displacement over force.

Mode Indicator Functions

Normal MIF; Sum of absolute values; Multivariate MIF for multiple reference FRFs.

Modal Parameter Estimation

SDOF estimation of pole and residue from single FRF; MDOF (Prony) method for estimation of poles and residues from single FRF with stability diagram; Global Least squares complex exponential method for estimation of poles with stability diagram; Polyreference Time Domain for estimation of poles with several references, with stability diagram; Add, delete or adjust poles locally for optimized fit (using a nonlinear least squares fit).

Modal Residue Estimation (Mode Shapes)

Least squares time domain method; Least squares frequency domain; Singular value decomposition for repeated modes.

Auxiliary Modal Parameter Tools

Conversion of poles to frequency/damping; Conversion of frequency/damping to poles; Modal Scaling for unity modal mass, unity length, unity max mode coefficient.

Model Evaluation Tools

Cross MAC matrix computation and plots; CoMAC; Modal complexity factor 1; Modal complexity factor 2;

Forced Response Computation

Fast method using digital filter implementations of modal superposition: impulse and ramp invariant methods. Computes velocity or displacement outputs from input forces, based on mass, damping and stiffness matrices (M, C, K), or based on M, K and modal damping, or based on poles and residues; Relative error as a function of frequency can be computed in each case.

Mechanical Simulation

Estimation of poles and residues from M, C, K matrices; Estimation of residues for single reference location; Estimation of residue matrix from single or multiple reference residue vector/matrix.

Structural Modification

SMURF algorithms for: added mass in a dof; added stiffnes and/or damping between a dof and ground; added stiffener or damper between two dofs; added tuned damper in a dof; constraining dofs.

Signal Analysis

Estimate multiple-input-multiple-output (MIMO) cross spectral matrices from time data; Estimate MIMO frequency responses (FRFs) from cross spectral matrices, including multiple coherence; Estimate impulse response functions from (single-sided) FRFs; Estimate conditioned signals including partial coherence, partial coherent output spectrum, L-systems.

Principal Component analysis

Estimate principal response spectra from cross spectral matrices; Estimate virtual coherence functions from cross spectral matrices.

Operating Deflection Shapes

Phased spectrum computation; Extraction of ODS shapes and frequencies.

Graphing

Real-/Imaginary plot of FRF; Nyquist plot of FRF (imaginary part as function of real part); Comparison plot of measured/synthesized FRF for modal model. MAC matrix 2D color plot; MAC matrix plot in 3D monochrome Manhattan style.

Overview

DuraTools is an add-on toolbox for durability analysis and fatigue analysis. It contains functions for traditional analysis such as rainflow analysis, Palmgren-Miner cumulative damage estimation and shock response analysis. In addition, it contains advanced functions such as fatigue damage spectrum and response equivalent peak velocity according to ISO TS 10811-1. Some functions for simulation of mechanical systems are included, including the proprietary method for time domain forced response computation also included in ModalTools. With DuraTools you have all the tools you need to transform operating data into vibration test specifications, be it sine, random or shock tests.

Specifications:

Level Crossing	Standard level crossing; Frequency dependent level crossing.
Rain Flow Analysis	Peak-valley conversion of time data; Rainflow cycle count; Range pair cycle count; Rain flow cycle count 2D plot versus range; Rain flow cycle count 3D plot versus mean and range; level crossing to rain flow conversion.
Fatigue Analysis	Palmgren-Miner cumulative damage computation
Environment Classification	Signal classification according to ISO TS 10811-2 for finding test specifications for sine testing; Classification plot according to ISO TS 10811-2.
Signal Analysis	Synthesis of frequency response from mass, damping, and stiffness matrices; Quantization of signals; Smoothed PSD estimate.
Statistics	Student t-test; Approximation of probability density function with three normal distributions.
Shock Response Analysis	Shock response min, max, and maximax; Pseudovelocity maximum response (or response equivalent peak velocity) calculation according to ISO TS 10811-1; Computation of time responses from shock response models including pseudovelocity max response; Shock indicator function, test if a signal contains shocks of significant levels.
Fatigue Damage Spectrum	Fatigue damage spectrum in acceleration or displacement; PSD to Fatigue Damage Spectrum, in acceleration or displacement.
Time Data Filtering	SDOF system relative displacement filter; SDOF pseudovelocity filter, Q normalized and ramp invariant.
Time Data Synthesis	Synthesize time data with a given PSD; Synthesize time data with a given pseudovelocity max response spectrum.
Forced Response Computation	Fast method using digital filter implementations of modal superposition: impulse and ramp invariant methods. Computes velocity or displacement outputs from input forces, based on mass, damping and stiffness matrices (M, C, K), or based on M, K and modal damping, or based on poles and residues; Relative error as a function of frequency can be computed in each case.
Synthesize FRFs	Synthesize frequency response functions (FRFs) from M, C, K matrices: receptance, mobility, and accelerance format.
Maps	Pseudovelocity max response map; Shock Response map.
Environment Classifikation	Classification of Vibration Sensitivity Spectrum.

Specifications*:

* Specifications and functionality claims are based on current version release and are subject to modification without notice. Please refer to our web site for complete and up-to-date version levels.

Forced Response	Computation of output displacement or velocity for known force input
Linear Systems	inear system with M, C, and K formulation; Computation of output displacement or velocity for known force input on linear system with M, K, and modal damping; Computation of output displacement or velocity for known force input on linear system with modal model (residues and poles). The algorithms are unique, extremely fast digital filter implementations.
Forced Response, Nonlinear Systems	Computation of output displacement or velocity for known force inputs for nonlinear MDOF systems with: (i) a nonlinearity in the excited DOF, (ii) arbitrary nonlinearity anywhere in the structure. The algorithms are unique, extremely fast digital filter implementations.
Signal Generators	Generation of linear and logarithmic sine sweeps. Generation of true or burst random with arbitrary PSD.
Simulated Experimental analysis	Harmonic balance analysis on any time signals. Tracking Filters for tracking sweeping sine waves.
MIMO Frequency Response Estimation	Methods for analyzing nonlinear SISO systems by equivalent MISO (Multiple-Input-Single-Output) systems with methods developed by Julius Bendat. Including multiple coherence, partial coherence, cumulated coherence. Complete MIMO estimation from measured or simulated time signals.

NOTE: Axiom EduTech AB reserves the right to change the specification without prior notice.

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