Browsers supply a great deal of view-related functionality by listing the parts of a model in a tabular and/or tree-based
format, and providing controls inside the table that allow you to alter the display of model parts.
FE geometry is topology on top of mesh, meaning CAD and mesh exist as a single entity. The purpose of FE geometry
is to add vertices, edges, surfaces, and solids on FE models which have no CAD geometry.
Tools and workflows that are dedicated to rapidly creating new parts for specific use cases, or amending existing
parts. The current capabilities are focused on stiffening parts.
The AutoBush is a bushing model that is designed to easily simulate bushings used in ground vehicles. The AutoBush entity
reads bushing stiffness (force-displacement) and damping (force-velocity) data from a file written in the TeimOrbit format.
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 Model Identification Tool (MotionView) is a utility in HyperGraph that you use to fit experimental data to various bushing models. The MotionView generates a General Bushing System file, .gbs file, which defines the bushing properties.
You can add an Altair Bushing Model, also known as AutoBushFD, a frequency-dependent bushing, to your MotionView model using the Add Auto Entity tool in MotionView.
The friction torque resists rotation of the bodies relative to one another. The friction model supports stiction and
sliding effects as well as a measured friction torque due to preload in the bushing.
Use Mount Stiffness when you want to approximate the structural deflection of the bodies that the bushing connects
due to the load that the bushing carries. Mount stiffness is modeled as a set of linear springs and dampers in series
with the bushing stiffness and damping, thus softening the connection between the bodies. Alternatively, you can use
flexible bodies to model the bodies the bushing connects.
You can activate Mount Limits to simulate material contact between the bodies that the bushing connects. This contact
limits the bushing deflection. When the deflection is sufficient in a given direction to close the gap distance, the
mount limit forces or torques become active. The forces and torque are computed using an impact function. An exponent
greater than one (1) provides increasing stiffness with penetration. The damping force is smoothed with a cubic step
function over the penetration distance.
In addition to adding a single bushing to your project, you can also add a pair of bushings such as AutoBushFD pair.
When you add a pair, MotionView automatically reflects modifications you make on the left bushing of the pair to the right bushing, unless you choose
otherwise. MotionView assumes bilateral symmetry about the global X-Z plane.
The AutoDamper entity is a force-velocity model designed to easily simulate a shock absorber used in ground vehicles.
The AutoDamper entity reads force-velocity data from a file written in the TeimOrbit format.
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.
You can activate Mount Limits to simulate material contact between the bodies that the bushing connects. This contact
limits the bushing deflection. When the deflection is sufficient in a given direction to close the gap distance, the
mount limit forces or torques become active. The forces and torque are computed using an impact function. An exponent
greater than one (1) provides increasing stiffness with penetration. The damping force is smoothed with a cubic step
function over the penetration distance.
You can activate Mount Limits to simulate material contact between the bodies that
the bushing connects. This contact limits the bushing deflection. When the deflection is
sufficient in a given direction to close the gap distance, the mount limit forces or torques
become active. The forces and torque are computed using an impact function. An exponent
greater than one (1) provides increasing stiffness with penetration. The damping force is
smoothed with a cubic step function over the penetration distance.
The figure below illustrates the concept of positive and
negative gap for mount limits in a bushing:
Click Activate to enable the options.
For Gap, enter a positive real value giving the bushing
deflection where the bodies contact. The limit force or torque is zero until the
bushing deflection closes the corresponding gap. The dimension is length.
For Stiffness, enter a positive real value giving the
limit stiffness for the given direction.
Note: Translation dimensions are force and length-1. Rotational
dimensions are force, length, and angle-1.
In the Exponent field, enter a positive real value
giving the power penetration is raised to. An exponent greater than one (1.0)
gives increasing stiffness with penetration.
For Damping, enter a positive, real value for the
damping coefficient.
Note: Translation dimensions are force, time, and length-1.
Rotational dimensions are force, length, time, and
angle-1.
For Penetration, enter a positive, real value giving the
penetration at which the damping is fully effective. Damping forces and torques
are smoothed by cubic step function over the penetration to prevent
discontinuity of the damping force or torque. The dimension is length.