Evaluation of vibration mode shape using a mechanoluminescent sensor

Abstract

This study proposes a method to measure vibration mode shape on beam structures by using the elastic mechanoluminescent (EML) material SrAl2O4: Eu2+. The EML phenomenon has attracted interest due to its potential for application to strain distribution, crack visualization, and structural health monitoring. In this Letter, the relationship between the distribution of luminous intensity and the vibration mode shape of beam structures is explored and is found to be quadratic. A comparison between the results of experiments and simulations shows that the proposed method can measure a structure's vibration mode shape. The study also shows that experimental parameters, such as the exposure time of the camera and the amplitude of excitation, do not affect the validity of this method. The robustness and convenience of the proposed method make it a more efficient technique than prevalent electrical or optical vibrational methods of analysis.