News & Updates

This page contains the latest information on the VIBES toolbox for MATLAB. New releases are announced here, together with a listing of new features. Expand the sections to read more about a feature.

July 17, 2018

VIBES Toolbox update 2.1.1

Update 2.1.1 of the VIBES toolbox for MATLAB adds the option to generate "RBE3" elements for numerical models using virtual points. RBE3 elements are commonly used in finite element modelling to generate a virtual "slave" node, that depends on the dynamics of its neighbouring ones. These nodes are typically associated to 6 DoFs to describe translations and rotations. In that sense, they can be seen as the numerical counterpart of the (experimental) virtual point. As from release 2.1.1, they can be computed using the vibes.VirtualPoint class too. The workflow is:

  1. Define one or more virtual point(s) that act as RBE3 elements;
  2. For each virtual point, choose the nodes in the model that act as the "master" nodes for the virtual point; set their grouping property accordingly;
  3. Generate FRFs using the vibes.ModalModel.toFRFMatrix method and specify the virtual points as the inputs.
Examples are found in the documentation of the vibes.ModalModel.toFRFMatrix method.

Other updates:

  • MCKModel substructures can be coupled with more than 2 at the same time, using the plus operator.
  • Minor bug fixes.
  • Improved support for MATLAB R2015b.

June 19, 2018

VIBES Toolbox update 2.1.0

Update 2.1.0 of the VIBES toolbox for MATLAB fixes some bugs of 2.0.0, adds documentation, primal coupling and decoupling of MCKModel objects and adds an interesting tutorial on substructuring of a crane from 3 substructures.

  • New tutorials vibesFemCrane and vibesFemCraneDS3 have been added. These tutorials demonstate the capabilities for primal and dual assembly using either numerical models (represented by objects of type vibes.MCKModel) or frequency-based admittance models (as vibes.FRFMatrix objects).
  • An install script is provided in the *.zip file of the VIBES Toolbox, which uninstalls previously installed toolboxes and checks important configurations. The installer *.mltbx itself is now much smaller, as datasets used for tutorials and help examples are now generated from a minimum set of data.
  • Improved support for MATLAB R2015b.
  • Bugfixes, mostly on the numerical modelling classes.

May 14, 2018

MAJOR RELEASE: VIBES Toolbox 2.0

Major release of the VIBES Toolbox version 2.0. The update is the most comprehensive so far, with amongst others:

  • Open code for most function class methods.
  • Auto-complete on many functions and methods for MATLAB versions > 2016b.
  • Complete overhaul of the numerical modelling and analysis side. New classes vibes.Node, vibes.DoF, vibes.VirtualPoint and redesign of vibes.MCKModel and vibes.ModalModel.
  • Animated mode shapes for numerical models.
  • Support for flexible virtual points using new definitions for DoF types.

A more detailed list of changes will follow soon.

July 28, 2017

VIBES Toolbox update 1.1.5

Update 1.1.5 of the VIBES toolbox for MATLAB comes with the following main improvements on the 3D viewer:

  • The 3D viewer has been upgraded with improved context menu's, options to load / save geometries and the ability to do simple geometry transformations such as scale, move, and rotate. This is especially convenient when importing STL geometries that have different coordinate systems. Once the objects have been imported and correctly scaled and positioned, all geometries can be stored to a single MAT-file for easy retrieval of the scene.
  • Camera control in the 3D viewer is now much more intuitive. A coordinate system triad has been added that always shows the orientation of the X, Y and Z-direction. Double-clicking on a structure will set the camera target to that point; while shift-double-click also orientates the camera in the direction of the face normal.

May 1, 2017

VIBES Toolbox update 1.1.2

Update 1.1.2 is now compatible with MATLAB versions 2015b 32/64-bit and newer.

April 20, 2017

VIBES Toolbox version 1.1.0 is now available

The latest update of the VIBES toolbox for MATLAB comes with many functional upgrades, lots and lots (and lots) of minor bug fixes and a full revision of the documentation.

Documentation & data-management

Major revision of the documentation: most common class methods and functions are documented, including some technical background information and equations.

Toolbox documentation is now directly available using the command vibes.doc, or vibes.doc(topic) where topic can be a class name, a class method or a function.

Multi-level repository browser for three-level project management.

The repository browser can be called by the command vibes.browse. It now offers three levels of data management, namely "Environment" (e.g. company, university, organisation), "Project" and an unlimited number of "Repositories", i.e. data resources. These repositories do not need to share the same root folder and may include different drives or network locations.

Repository manager to simplify management of the repositories.

A convenient user interface has been added that allows to create, change or remove repositories.

Customization of toolbox classes has now been made easier with illustation of class extension and method overloading.

The toolbox includes a tutorial vibesClassExtension which demonstrates how to extend a built-in class, define additional properties and methods.

Substructuring & experimental modelling

Primal and dual substructure coupling to allow for admittance and impedance coupling.

Subsystem admittances and impedances can now be coupled using the commands:

YAB = couple(YA,YB);
ZAB = couple(ZA,ZB);

In case of admittance, the LM-FBS algorithm will be used for dual assembly. In case of impedance, the subsystem matrices are added in a primal fashion.

Improved automatic DoF matching in many matrix operations such as matrix-inversion, multiplication, plus and minus.

Proper bookkeeping of nodes, DoFs, directions and quantities is essential to prevent making mistakes in your calculations. In all arithmetic operations involving vibes.FRFMatrix and vibes.FreqBlocks objects, such as a matrix inverse operation f = Y \ u, DoFs are automatically searched for in the two objects that have matching position, direction, unit and grouping. This way, one can never add "apples to pears" and the toolbox returns information about which DoFs have been matched in both objects.

Improved FRF consistency functionality assisting you to evaluate the quality of your experimental model.

The FRF consistency function uses the Virtual Point Transformation to evaluate how consistent sensor displacements and force excitations are with respect to each other. For instance, this allows to evaluate the consistency of entire columns or rows of an FRF matrix.

The toolbox includes a tutorial vibesExperimentalModelling, demonstrating the various options of the consistency function.

Transfer path analysis & mathematics

Improved matrix-inversion for force identification with options for singular value truncation and matrix (Tikhonov) regularisation.

The matrixinverse method of the vibes.FRFMatrix class calls the vibes.math.matrixinverse function, which accepts arguments for additional control over the matrix inversion.

Balancing Balancing of the matrix columns (useful in case of different quantities)
SingularValues Truncation using a selection of singular values
RelThreshold Truncation using a relative threshold on the singular values
AbsThreshold Truncation using an absolute threshold on the singular values
DampingFactor Damping of singular values using a Tikhonov factor
CustomFunction Full customisation using the ability to specify your own algorithm for matrix inversion
Several of the above options are demonstrated in the vibesBlockedForceTPA tutorial script.

Insight in mathematic operations by being able to "step in" the m-files that perform the calculations.

All functions in the packages vibes.math are included as m-files, such that one is able to follow the operations step-by-step.

Numerical (FE) modelling

Improved support for numerical models with upgrades on the classes vibes.MCKModel and vibes.ModalModel.

The vibes.MCKModel and vibes.ModalModel classes are neatly integrated to quickly evaluate the effect of e.g. different modal damping parameters. Mode shapes can be plotted and animated with color maps.

March 3, 2017

VIBES Toolbox version 1.0.3 is available

The first release of the VIBES toolbox for MATLAB.