The invention relates to an
optical fiber grating vibration sensor comprising double
cantilever beams with equal strength, a
cantilever beam base is arranged on the left side in a housing, the fixing ends of the upper sheet-like
cantilever beam and the lower sheet-like cantilever beam, which are parallel to each other are connected with the cantilever beam base into a whole, the free ends are arranged on the upper side surface and the lower side surface of a
mass block, cantilever beam position-limiting columns which are vertical to the surfaces are arranged on the surfaces which are respectively parallel to the plane of the upper cantilever beam and the plane of the lower cantilever beam of the
mass block, a sealing cover which is equipped with a sensor joint on the outer side is arranged at the open end of the housing, an
optical fiber protective casing penetrating the center of the sealing cover and the center of the sensor joint is arranged on the sealing cover, the ratio of the width of the fixing ends of the upper cantilever beam and the lower cantilever beam to the width of the free ends is 5 at least, an upper sensing
optical fiber grating is arranged on the upper surface of the upper cantilever beam, a lower sensing optical
fiber grating is arranged on the lower surface of the lower cantilever beam, and the series connection output end of the upper sensing optical
fiber grating and the lower sensing optical
fiber grating penetrates out of the optical fiber protective casing. The optical fiber grating
vibration sensor has good sensitivity, reliability and stability.