Low-frequency micro/nano-vibration generator using a piezoelectric actuator
Low-frequency vibration must be detected because of its harmful effects on micro/nano measuring machines. Thus, the authors developed a low-cost and high-precision detector for low-frequency micro-vibration. A high-precision vibration generator is required to calibrate the vibration detector because of the high cost and complex structure of existing vibration generators. A new vibration generator that can produce low-cost and high-precision lowfrequency vibration was also developed. A piezoelectric actuator is used as a vibration exciter, which is driven by a high-precision signal generator and a high-voltage amplifier. A beryllium bronze-based leaf spring was used as an elastic component, which is optimally designed and verified by the ANSYS software. The proper size and natural frequency of the leaf spring were obtained. The leaf spring was fixed horizontally on a four-point cylinder-shaped pedestal and driven by the actuator vertically. The worktable on the top surface of the leaf spring only had an up-and-down direction. A high-precision eddy current sensor was used to test the performance of the developed vibration generator. Experimental results show that the vibration generator can produce simple harmonic vibrations with a frequency and amplitude ranges of 10–50 Hz and 0.90–19.87 μm, respectively, and the repeatability of the open-looped vibration amplitude is less than 90 nm (K=2). The developed vibration generator can be used when a micro/nano-vibration detector is calibrated.