Scanning laser vibrometry of the dynamic rundown and out-of-plane vibration for MEMS

Abstract

The microelectromechanical system (MEMS) turbine examined for dynamic rundown and rotary vibration in this paper was the first using axial airflow for low air pressure response and high output. The effect of friction on device performance was measured from the dynamic rundown in revolutions per minute due to bearing friction and planar/non-planar rotor vibration. These tests showed that the scanning laser vibrometer is indeed suited to testing the microturbine. Plots were generated and built up to show the magnitude of the vibration at different points. Here the authors show that the scanning laser vibrometer is capable of making the required rundown and planar/non-planar measurements under non-standard conditions. Measuring the planar/non-planar vibration of the rotor is difficult on the microscale but is essential if one wishes to provide feedback to the design-to-fabrication process and improve device efficiency. The results of the presented work represent scientific activities in MEMS and are useful not only for physicists but also for industrial application.