.. _auto_curve_psi_calculator:

*COMPUTE A PSI FROM VEHICLE ACCELERATION*
=========================================

Computes the Pulse Severity Index (PSI) from a vehicle acceleration time-history given in Gs per millisecond. Applies user-supplied time and acceleration scale factors before integration. Use this worker whenever a PSI injury-risk metric is needed from raw crash acceleration data.

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

Classification: **process**.

Tagged: ``crash``, ``gs``, ``injury_criteria``, ``psi``, ``pulse_severity_index``, ``scale_factor``, ``time_history``, ``vehicle_acceleration``.

Inputs
------

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

   * - Label
     - ID
     - Type
     - Default
     - Required
     - Description
   * - Vehicle Acceleration Time-history In Gs Per Millisecond
     - vehicle_accelerationtime-historyin_gspermillisecond
     - vector
     - —
     - 
     - Vehicle acceleration time-history curve (X = time in milliseconds, Y = acceleration in Gs); connect the binout/d3plot-extracted resultant acceleration channel here.
   * - time_sf
     - time_sf
     - scalar
     - 1
     - 
     - Multiplicative scale factor applied to the time axis before PSI integration (dimensionless, default = 1.0; change only if the input curve time units differ from milliseconds).
   * - acc_sf
     - acc_sf
     - scalar
     - -9.81
     - 
     - Multiplicative scale factor applied to the acceleration axis before PSI integration (default = -9.81 to convert from Gs to m/s²; adjust sign and magnitude to match the input curve's sign convention and units).

Outputs
-------

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

   * - Label
     - ID
     - Type
     - Description
   * - curve_psi_calculator_output_1
     - curve_psi_calculator_output_1
     - keyvalue
     - Key-value result set containing the computed PSI scalar value (dimensionless) derived from the scaled acceleration pulse.

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

- data.curve.transform
- data.signal_processing
- engineering.crash.occupant_safety

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

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

.. raw:: html

   <hr style="margin-top:2em">
   <p style="font-size:11px;color:#888">
   Auto-generated from <code>transformation</code> schema. Worker id: <code>curve_psi_calculator</code>. Schema hash: <code>e14a2812a56c</code>. Hand-curated docs in <code>workerexamples/</code> override this page when present.
   </p>