Combining the corrugated diaphragm with a fiber-optic Bragg grating,a novel fiber-optic grating seepage pressure sensor is designed.The deflection change of the corrugated diaphragm is transformed to the axial strain change of the fiber-optic Bragg grating through a draw-bar type structure.Through pressure calibration experiments at constant temperature,the pressure sensitivity of the sensor is about 20 nm/MPa,which increases 6 000 times compared with general fiber-optic gratings.In order to eliminate the i...