DISP TO ENERGY DENSITY VS TIME¶
Converts a displacement–time curve into an Acceleration Injury Threshold (AIT) energy-density-vs-time curve by differentiating twice to obtain acceleration, optionally scaling axes, and applying a selectable low-pass filter. Use this worker when you need to derive AIT injury metrics directly from raw displacement time-history data.
When to use¶
Classification: process.
Tagged: AIT, CFC, SAE, acceleration, crash, curve_transform, disp_to_ait, displacement.
Inputs¶
| Label | ID | Type | Default | Required | Description |
|---|---|---|---|---|---|
| Base Curve | base_curve | vector | — | Input displacement–time curve (vector of [time, displacement] pairs) to be transformed into an AIT energy-density curve; leave empty only if the curve is supplied upstream in the workflow. | |
| X Sf | x_sf | scalar | — | Multiplicative scale factor applied to the time axis (x-values) before processing; defaults to 1.0 (no scaling) if left blank. | |
| Y Sf | y_sf | scalar | — | Multiplicative scale factor applied to the displacement axis (y-values) before processing; defaults to 1.0 (no scaling) if left blank. | |
| FilterType | filter_type | scalar | lsprepost_sae | Low-pass filter algorithm applied to the differentiated acceleration signal; choose from lsprepost_sae (default), lsprepost_bw, lsprepost_cos, lsprepost_fir, cfc, or sae — match the filter convention used in your post-processing tool. | |
| Frequency | frequency | integer | 300 | Cut-off frequency (Hz) for the selected filter; standard crash-channel values are 30, 60, 120, 180, 300 (default), 600, or 1000 Hz — select per the applicable injury-channel class (e.g., SAE 300 for head/chest). |
Outputs¶
| Label | ID | Type | Description |
|---|---|---|---|
| curve_disp_to_ait_output_1 | curve_disp_to_ait_output_1 | vector | Resulting AIT energy-density–vs–time curve (vector of [time, energy-density] pairs) derived from the scaled, filtered, and twice-differentiated input displacement signal. |
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_disp_to_ait
Auto-generated from transformation schema. Worker id: curve_disp_to_ait. Schema hash: 36c692d90137. Hand-curated docs in workerexamples/ override this page when present.