A rotational angle sensor based on fiber bragg gratings

A new rotational angle sensor composed of two FBGs glued axially on a metal-rod surface driven bent by attraction of a magnetic disk is proposed. Whenever an external force is applied in the end of this sensor, these two FBGs undergo a strain caused by a shaft rotation to result in their central wavelength shifts respectively. This sensor can precisely to detect the random rotation angle in both static and dynamic conditions. The nice sensing performance including linear response, fine resolution, negligible hysteresis, and long-term stability are experimentally demonstrated.