The Altair GUI Toolkit is a resource tool for coding Tcl/Tk dialogs. It contains documentation of the HyperWorks commands, demo pages that illustrate our Altair GUI standards, and sample code for creating those examples.
The Model Identification Tool, known as HyperWorks, is a profile in HyperGraph for fitting test data from frequency- and amplitude-dependent bushings to analytical models. The HyperWorks operates in conjunction with HyperGraph, MotionView and MotionSolve to provide you with a comprehensive solution for modeling and analysis.
The Altair Bushing Model is a library of sophisticated, frequency- and amplitude-dependent bushing models that you can use for
accurate vehicle dynamics, durability and NVH simulations. The Altair Bushing Model supports both rubber bushings and hydromounts.
This section provides information about using the Altair Bushing Model, also known as AutoBushFD, with MotionView. The Altair Bushing Model is a sophisticated model that you can use to simulate the behavior of bushings in vehicle
dynamics, durability and NVH simulations.
The bodies connected by the bushing are flexible and may deflect under the load being transmitted. This phenomenon
is modeled with the Mount Stiffness feature. Mount stiffness models the structural stiffness of the bodies, thus mounting
the bushing as a linear spring and damper in series with the bushing in each direction.
The Altair Bushing Model includes a Mount Limits feature, which lets you model the material contact that occurs between
the bodies that a bushing connects. The bodies are flexible and may deflect under the load being transmitted. Given
enough bushing deflection, the bodies may contact one another for negative and positive deflections in each
direction.
This section describes how preloads, offsets and scales enter into bushing force computations. You use Preloads, Offsets
and Scales to alter the operating point of a bushing. You can offset the bushing displacement in any direction, and
scale the input displacement and velocity. You can also offset the bushing force in any direction by adding
a preload or scale-output force or moment in any direction.
Coupling refers to the forces and moments generated in a bushing to oppose the overall deformation of the bushing.
These forces and moments are independent of any coordinate system that might be used to measure the deformation or
deformation velocity. Coupling is an important factor when the bushing characteristics are non-linear.
The System Performance Data file, *.spd, contains the test data used for fitting a bushing. This data should be validated to ensure that it is physically
meaningful. One test for physical consistency is that the dynamic stiffness at any amplitude of vibration must always
be greater than the static stiffness at the same amplitude.
HgTrans translates solver results files from their native file format to Altair Binary Format (ABF). This can be done using
the HgTrans GUI or via the HgTrans batch mode.
The HyperWorks Automation Toolkit (HWAT) is a collection of functions and widgets that allows an application to quickly assemble
HyperWorks automations with minimal effort and maximum portability.
HyperWorks Verification and Validation Harness (HVVH) is a tool that can be used to verify and validate HyperWorks products. End users can use this tool to quickly evaluate the software quality, performance, reliability,
scalability, and robustness, and to gain more confidence in HyperWorks products.
Uninstall HyperWorks is a tool to launch the HyperWorks uninstallation program. This program contains two options that allow you to either remove the originally installed
files, or remove all the files that resides in the installation directory.
The Model Identification Tool, known as HyperWorks, is a profile in HyperGraph for fitting test data from frequency- and amplitude-dependent bushings to analytical models. The HyperWorks operates in conjunction with HyperGraph, MotionView and MotionSolve to provide you with a comprehensive solution for modeling and analysis.
This model can be used for both dynamic and quasi-static tests.
The figure above-left shows a schematic of the bushing model where:
X is the input displacement provided to the bushing.
y and w are the internal states of the
bushing.
and represent the bushing rubber stiffness.
is used to control the stiffness at large
velocities.
produces the roll-off observed in the
experimental data at low velocities.
accounts for the relaxation of the bushing
impact force.
represents the viscous damping observed at
large velocities.
The governing equations for this bushing are shown above-right where:
R is the cutoff frequency associated with a first order
filter that acts on the input X.
x is the dynamic content of the bushing input
X. This is the filter output.
and
are the time derivatives of
the internal states of the bushing y and
w.
K is the effective stiffness of the bushing.
C is the effective damping of the bushing.
Spline (X) is the static force response of the
bushing.
The effective stiffness K and effective damping
C are dependent on nonlinear effects such as friction in the
bushing material and other nonlinear behavior that cannot be easily represented
physically.
The effective stiffness K is multiplied by a factor:
Similarly, the effective damping C is multiplied by a factor:
The total force generated by the bushing is the sum of 2 forces: