Fiber Bragg grating-based method for underwater object angular measurement

Abstract In this paper, we present a underwater object angular measurement method that is composed of a novel fluid pressure sensor and a algorithm for angle measurement. The innovative pressure sensing structure, incorporating four fiber Bragg g ratings, demonstrates remarkable sensitivity to fluid pressure, achieving a resolution of 1.3 pm μ ϵ −1 . Based on this unique structure, we have developed an algorithm that utilize the characteristics of Bragg grating signal to determine the angular position of the vibration source. Through several different experiments, we evaluated the performance of pressure sensor and accuracy of angular algorithm. The results indicated that our algorithm achieves a mean absolute error of 2.3 degrees, coupled with a root mean square error of 3.1 degrees, demonstrating its high precision in determining the angular position of the vibration source. Furthermore, the practicality and robustness of this method has been validated in complex flow fields, demonstrating its promising application in underwater environment monitoring.