Application of single mode optical fiber sensors in structural vibration suppression

Optical fibers are small, lightweight, and flexible that can operate over a wide range of environmental conditions and respond to many physical properties. This paper presents two single-mode Michelson interferometric optical fiber sensors for the vibration control application of smart structures. Analysis and experiment show that the length and location of the sensing fiber in the smart structure has to be carefully selected such that the structural vibration amplitude is within the sensor measurement range for linear output. Experiments are also conducted by feeding back the fiber sensor signal to the piezoelectric actuator embedded inside the smart structure so as to suppress structural vibration. The results show that both optical fiber sensors - one with an external piezoelectric modulator and the other with an internal frequency modulated light source - are effective in vibration control application.