Force sensing with temperature self-compensated based on a loop thin-wall section beam

A novel method about force sensing with temperature self-compensated based on a loop thin-wall section beam is proposed and demonstrated. Two identical fiber Bragg gratings are rigidly affixed on the outer surface of the beam with the positional angle difference between the two gratings of 90 degrees. The wavelength space between the two reflected peaks of the gratings is proportional to the force and insensitive to temperature when the direction of the force and one of the two gratings are located along a diameter; therefore, the force sensing with temperature self-compensated can be achieved.