Signal processing is in fact a wide subject. Based on my limited experience, your observation is correct; there is more literature recently on the rolling element bearings compared to fluid film bearings.
With respect to the wavelet analysis, it gained a little interest in the common industry compared to fft. Many practionors do not know what a wavelet is or how it could used in practical machinery vibration analysis.
Having said that, I would recommend to identify the scope of your research /psper. If you are in a bachelor's program, typically students are not expected to come up with "new knowledge". So, maybe focusing on the technology being used in the industry could be better specially if your internship will be in the industry. For example wavelet and many other topics in the signal processing should have a much lower priority for you if my assumptions are correct. To avoid unnecessary hardship in your paper, it would be useful if you can know the type of machines (rolling element or journal bearings, size, layout etc) operated in your internship's place. Also, focus your study of signal processing on the system they use (what brand, what model, functions offered etc). Aligning your preperation now with what you will face in the internship would be a high consideration.
Again good luck.
Regards- Ali M. Al-Shurafa