A Wide-Range Displacement Sensor Based on Plastic Fiber Macro-Bend Coupling

Jia Liu,Jijun Xiong,Yulong Hou,Guocheng Fang,Shan Su,Huixin Zhang,Pinggang Jia,Wenyi Liu

doi:10.3390/s17010196

Abstract

This paper proposes the strategy of fabricating an all fiber wide-range displacement sensor based on the macro-bend coupling effect which causes power transmission between two twisted bending plastic optical fibers (POF), where the coupling power changes with the bending radius of the fibers. For the sensor, a structure of two twisted plastic fibers is designed with the experimental platform that we constructed. The influence of external temperature and displacement speed shifts are reported. The displacement sensor performance is the sensor test at different temperatures and speeds. The sensor was found to be satisfactory at both room temperature and 70 °C when the displacement is up to 140 mm. The output power is approximately linear to a displacement of 110 mm–140 mm under room temperature and 2 mm/s speed at 19.805 nW/mm sensitivity and 0.12 mm resolution. The simple structure of the sensor makes it reliable for other applications and further utilizations, promising a bright future.

Highlights

Displacement is an important physical quantity of solid mechanics, and displacement measurements are required in a variety of applications, such as precision alignment, position monitoring, vibrations analysis and robotics [1–3]
This paper further proposes a wide-range displacement sensor, the strategy and fabrication of an all plastic fiber wide-range displacement sensor, by using the macro-bend coupling effect which causes power transmission and variation between two twisted bending plastic optical fibers
The radius of macro-bend decreases with the connected displacement the output power changes connected to a Power and

Summary

Introduction

Displacement is an important physical quantity of solid mechanics, and displacement measurements are required in a variety of applications, such as precision alignment, position monitoring, vibrations analysis and robotics [1–3]. Based on the fiber fundamental core mode coupling and the Whispering Gallery modes (WGMs) induced by the reflection at the clad-coat interface, a length of acrylic jacket fiber has been stripped, coated with absorbent coating material This paper further proposes a wide-range displacement sensor, the strategy and fabrication of an all plastic fiber wide-range displacement sensor, by using the macro-bend coupling effect which causes power transmission and variation between two twisted bending plastic optical fibers. This structure has a good robustness and the fiber does not need pretreatment. The retrace error of the system is less than 0.05 nW/mm

Sensor Design and Sensing Principles

Output

Conclusions