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.
Define the Friction
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.
Define the Mount Stiffness
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.
Define the Mount Limits
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.