The correct sample rate?

Plz :cry: i need an advice about using correct sample rate for my project.
I am working on low cost (Vibrometer) device, my target frequency between (0.5~80 Hz). What is correct sample/sec should i use?

the minimum sampling rate is at least twice the highest frequency you require - see shannon-sampling-theorem
e.g. if you require 80Hz sample at 160Hz or better