Defining Butterworth Filters

You can use the Butterworth filter to filter output based on the cutoff frequency and filter order.

The Butterworth filter's response in the pass band is maximally flat.

See Also
About Output Filters
  1. From the Simulate section of the action bar, click Butterworth Filter .
  2. Optional: Enter a descriptive Name.
  3. Enter a value for the Cutoff frequency, which is the frequency above which the filter attenuates at least half of the input signal.
  4. Enter a value for the Order, which is a measure of the transition band.

    A higher value for the filter order results in a narrower transition band. However, there is a computational cost. As the order increases, the performance declines.

  5. Optional: From the Determine bounding value options, select one of the following:
    OptionDescription
    Maximum Applies a bounding limit for the maximum.
    Minimum Applies a bounding limit for the minimum.
    Absolute Maximum Applies a bounding limit for the absolute maximum.
    None Does not apply a bounding limit.
  6. Optional: Enter a value for the Bounding value limit, which enforces an upper or lower bound for the variables in the output request.
  7. Optional: Select Stop analysis upon reaching limit to stop the analysis if any of the variables reach the specified limit.

    Note: Along with the expected output variables, Mechanical Scenario Creation writes an additional field frame to the output file when this option is selected.

  8. Optional: From the Invariant options, specify whether this filter definition applies directly to the first- or second-order invariant.

    Invariants are tensor properties that do not change. For some variables, you can apply the filter directly to the first- or second-order invariant.

  9. Click OK.

The specified Butterworth filter is now available when you select a filter type when creating output requests.