Appendix 3: Explanation of Template Parameters

  1. Name of test - Instrument name and what you’ve named the test

  2. Date - Date and time of data collection

  3. Location - You can set this to show where you collected the data

  4. Template - Which template was used

  5. Set Names - Defines the hammer tap position. Most common ones are: H (horizontal), V (vertical), and H,V (horizontal, vertical), but you can name them whatever you want. Make sure to separate different position names with a comma.

  6. Positions - Number of positions to acquire data from, per set. The default is 1.

  7. Taps/Positions - Number of taps to complete a position. Collecting multiple sets of tap data from the same position and averaging them accounts for the random variability in the experiment. The default (and recommended) value is 5.

  8. Freq Resolution - What the frequency resolution on your FRF is.

  9. dB Offset - Adds a dB offset to your data, if you want.

  10. dB Spread - The number next to the Y scale above your plot.

  11. Soundcard Settings

    • Soundcard - Soundcard name, and the depth of the soundcard (e.g. 32 bit)

    • Sample time (s) - How long of a time snippet each sample takes.

    • Pre-trigger (s) - How far before the hammer hits sampling starts.

  12. Output Settings - The output, for this experiment, is the sound that the instrument makes, which is collected by the Microphone.

    • The number to the left of “Output” shows which channel it’s connected to, on your sound card.

    • Gain - Multiplication factor for the amplitude of the data collected from the microphone. If your sound peaks are small, try increasing this number, both on the template and on your soundcard.

    • Mic Cal - Conversion factor for the microphone.

    • Accel Cal - Conversion factor for the accelerometer.

    • Vibrometer Cal - Conversion factor for the vibrometer.

      • *TIP: See the section named “Calibration and Units” for instructions on how to find the suggested calibration factor.

    • Mic Cutoff - Sets everything after this point to 0, for noise reduction.

13. Trigger Settings - The trigger, which is the force applied to the bridge, is provided and sensed by the Hammer, for the experiment. You can change it to Self Tap to do a tap test.

    1. Gain - Multiplication factor for the amplitude of the data collected from the hammer. If your sound peaks are small, try increasing this number, both on the template and on your soundcard.

    2. Hammer Cal - Hammer calibration coefficient.

    3. Hammer Threshold - What is considered a hit, shown with a purple line on the test window plot.

    4. Double Bounce - If anything beyond the green line on the test window plot hits this number, it’s considered a “double bounce” and a bad run, so you’re prompted to retry the tap.

    5. Hammer Cutoff - Green line on the plot on the test window.

14. Vibrometer Settings - Establish all the settings under this section according to your vibrometer.

15. Arrays at the bottom - These are the x and y axis ranges on the plots.