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Detection rate as a function of nominal defect dimension_
| Nominal dimension [mm] | Detected / total | Detection rate [%] |
|---|---|---|
| 6 | 3 / 10 | 30.0 |
| 13 | 10 / 15 | 66.7 |
| 19 | 11 / 15 | 73.3 |
| 25 | 8 / 10 | 80.0 |
| 38 | 8 / 10 | 80.0 |
Summary of LPT detectability, sizing error, and repeatability by defect type_
| Defect type | Detected / total | Detection rate [%] | Mean error [mm] | Mean error [%] | Mean SD [mm] |
|---|---|---|---|---|---|
| Prepreg foil | 8 / 12 | 66.7 | −0.58 | −2.9 | 1.41 |
| Flat bottom hole | 10 / 12 | 83.3 | −2.61 | −12.4 | 1.33 |
| Paper inserts | 10 / 12 | 83.3 | 0.82 | 21.0 | 0.94 |
| Flat bottom hole filled with epoxy resin | 12 / 12 | 100.0 | 2.51 | 19.3 | 0.92 |
| Graphite foil | 0 / 12 | 0.0 | — | — | — |
Acquisition parameters_
| Parameters | Value |
|---|---|
| Sync Mode | Free run |
| Acquisition duration | 120 [s] |
| Acquisition frame rate | 5 [Hz] |
Excitation parameters_
| Parameters | Value |
|---|---|
| Modulation | Rect. |
| Amplitude low | 0 [%] |
| Amplitude high | 90 [%] |
| Excitation period | 120 [s] |
| Duty time | 10 [s] |
| Rising ramp time | 0.8 [s] |
| Falling ramp time | 0.8 [s] |
| Number of measurements | 359 |
| Best results measurement | 346 |