Plastic optical fibre physiological bending sensor based on fibre tilt angle loss measurement

This paper presents the development of bending sensor using plastic optical fibre. The bending angle is measured with respect to the changes in light intensity at the receiving fibre. To study the relationship between the sensor´s output intensity power and the bending angle, three mediums with different refractive index were used at the gap in between of the emitting and receiving fibres. It was found that, a higher refractive index medium could be used to improve the resolution of the sensor but with a reduced sensor working range.