Recommendations

Applying what was learned through this thesis, there are several recommendations that could aid and guide similar structural vibration projects. Although it did not affect the results, the sampling frequency erroneously set to 51.2 kHz created PSD result with many more data points than needed, which made the data processing less efficient. Properly setting the sampling frequency to twice the maximum expected frequency would allow for the data to be more manageable and to be processed quicker.

Regarding experimental equipment, this project proved that the data collected by the PCB accelerometer was not insightful to engineering a new stand design as the noise floor of the PCB (0.5 Hz) was too high to measure to the 0.2 Hz level of precision required to calculate and plot a discrete point for each one-third octave band center frequency in the VC-C curve. Instead, the Wilcoxon accelerometer with a noise floor or 0.05 Hz and a standard sensitivity setting of 10 V/g collected the most valid data for this project. Applying the knowledge that the Wilcoxon can only measure reliably up to 750 Hz, the sampling frequency on the DAQ could be set to 1500 Hz. This would naturally lower the amount of data collected and, as a result, could help show trends in a PSD more easily and with less data manipulation. Most notably, however, the processing time for this amount of data would be significantly faster.

This project also outlined how shock vibrations cannot be properly applied to PSD analysis and Environmental Vibrational Criteria because they were created to analyze ambient vibrational signatures. As a result, experimental vibrational data collected where shocks were induced in the system were not necessary to design the OAB stand or analyze the OPF stand; not collecting that data could save time in future projects where these vibrational criteria are applied.

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APPENDIX A. PSD TO VC REQUIREMENTS: MATLAB FUNCTION