.. _auto_curves_get_crashworthiness:

*COMPUTE THE AXIAL CRUSH OF A SET OF NODES*
===========================================

Computes axial crush (crashworthiness) metrics for a set of nodes by combining nodal coordinate time-histories with section-force time-histories. Use this worker to derive crush distance and energy-absorption curves from LS-DYNA binout/d3plot extracted signals for structural crash evaluation.

When to use
-----------

Classification: **process**.

Tagged: ``CFC``, ``LS-DYNA``, ``SAE_filter``, ``axial_crush``, ``crashworthiness``, ``crush_distance``, ``energy_absorption``, ``nodal_coords``.

Inputs
------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20 20 20

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Coords
     - coords
     - vector
     - —
     - 
     - Nodal coordinate time-history vectors (dimensionless index or mm/m units); ordering must match coord_input_order — either interleaved X₁Y₁Z₁X₂Y₂Z₂… (coords_xyzxyz) or blocked X₁X₂…Y₁Y₂…Z₁Z₂… (coords_xxyyzz). Supply at least two node positions to define the crush axis; optional if only force metrics are needed.
   * - Section Forces
     - section_forces
     - vector
     - —
     - 
     - Section-force time-history vector (typically kN or N) for the cross-section whose centroid lies between the two reference nodes; used to compute energy absorption and force-crush curves. Optional when only displacement crush is required.
   * - Coordinates Input Order
     - coord_input_order
     - string
     - coord
     - 
     - Selects the layout of the coords vector: 'coords_xyzxyz' for interleaved per-node triplets or 'coords_xxyyzz' for axis-blocked ordering; defaults to 'coord' (xyzxyz). Must match the extraction convention used when pulling coordinates from the solver output.
   * - Filter Force
     - filter_force
     - string
     - no
     - 
     - Toggles SAE/CFC low-pass filtering on the section-force signal before crashworthiness calculations; set to 'yes' to apply the filter at the frequency defined by filter_freq, or leave as default 'no' to use the raw signal.
   * - Filter Freq
     - filter_freq
     - scalar
     - 300
     - 
     - SAE/CFC filter cut-off frequency (Hz) applied to the force signal when filter_force is 'yes'; choose from 60 Hz (CFC 60), 180 Hz (CFC 180), or 300 Hz (CFC 300, default) per the relevant crash test channel class.
   * - Scale Factor
     - scale_factor
     - scalar
     - 1.0
     - 
     - Scalar multiplier applied to the computed crush or force values to handle unit conversions or sign conventions (e.g., −1 to flip compression-positive signals); leave at default (1.0) when no rescaling is needed.

Outputs
-------

.. list-table::
   :header-rows: 1
   :widths: 20 20 20 20

   * - Label
     - ID
     - Type
     - Description
   * - curves_get_crashworthiness_output_1
     - curves_get_crashworthiness_output_1
     - dataset
     - Dataset containing the computed crashworthiness curves and KPIs — including axial crush displacement (mm), section force (kN), and energy absorption (kJ) as time-series columns — ready for downstream response templates or visualisation workers.

Disciplines
-----------

- cae.postprocessing.response
- data.curve.transform
- data.signal_processing
- engineering.crash.dynamics

Runnable example
----------------

A runnable example is registered for this worker. Open the example workflow on the d3VIEW canvas: `/api/workflow/example?id=curves_get_crashworthiness <https://www.d3view.com/api/workflow/example?id=curves_get_crashworthiness>`_

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   Auto-generated from <code>transformation</code> schema. Worker id: <code>curves_get_crashworthiness</code>. Schema hash: <code>5bb6aac2790f</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
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