A Differential Reflective Intensity Optical Fiber Angular Displacement Sensor

Abstract

In this paper, a novel differential reflective intensity optical fiber angular displacement sensor was proposed. This sensor can directly measure the angular and axial linear displacement of a flat surface. The structure of the sensor probe is simple and its basic principle was first analyzed according to the intensity modulation mechanisms. Secondly, in order to trim the dark output voltage to zero, the photoelectric conversion circuit was developed to adjust the signals. Then, the sensor model including the photoelectric conversion circuit has been established, and the influence of design parameters on the sensor output characteristic has been simulated. Finally, the design parameters of the sensor structure were obtained based on the simulation results; and an experimental test system was built for the sensor calibration. Experimental results show that the linear angular range and the sensitivity of the sensor were 74.4 and 0.051 V/°, respectively. Its change rules confirm the operating principle of the sensor well.

An Optical Fiber Measurement System for Blade Tip Clearance of Engine

“…The OPT101 voltage output is 7.5 mV dc with no light and increases with increasing illumination. In order to trim the dark output voltage to zero, a low-impedance offset driver (op amp) was used to drive pin 8 (Common) of OTP101 because this node has signal-dependent currents [20]. The signal multiplication circuit was designed to improve the signal-to-noise ratio and ensure the accuracy of sampling data.…”

Periodic Nonlinear Error Analysis and Compensation of a Single-Excited Petal-Shaped Capacitive Encoder to Achieve High-Accuracy Measurement

“…The encoders are classified as optical, magnetic, inductive, and capacitive according to their measurement principle. Optical and magnetic encoders are dominant in the market as they can achieve high precision, but they tend to be relatively expensive and bulky [2,6,7,8,9,10]. Currently, capacitive encoders have been gaining interest owing to their simplified design, potential for further miniaturization, insensitivity to magnetic field variation, long lifespan, low cost, and high measurement accuracy [5,10,11,12].…”

“…While rotating, capacitances formed between plates change and the angle of shaft can be obtained. Many types of capacitive encoders have been proposed, and the most prominent is by modulating the angular information to two orthogonal triangular signals [6,7,8]. Encoders of this type have the advantage of high robustness to common mode errors.…”

An Optical Interferometric Triaxial Displacement Sensor for Structural Health Monitoring: Characterization of Sliding and Debonding for a Delamination Process

“…In comparison to traditional sensing technologies, optical fiber sensors offer great advantages, such as immunity to electromagnetic field, high sensitivity, small size, ease of fabrication, and robustness to harsh environments [ 11 , 12 , 13 , 14 ]. Given several choices of sensing mechanisms, such as wavelength modulation, phase modulation, and intensity modulation, optical fiber displacement sensors thrive on structural diversity and sensing properties [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ]. The majority of the reported optical fiber displacement sensors work in a one-dimensional fashion, meaning it is impossible to measure interfacial sliding and debonding at the same time [ 15 , 16 , 17 , 18 , 19 , 20 ].…”

“…Given several choices of sensing mechanisms, such as wavelength modulation, phase modulation, and intensity modulation, optical fiber displacement sensors thrive on structural diversity and sensing properties [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ]. The majority of the reported optical fiber displacement sensors work in a one-dimensional fashion, meaning it is impossible to measure interfacial sliding and debonding at the same time [ 15 , 16 , 17 , 18 , 19 , 20 ]. Several two- and three-dimensional (2D, 3D) optical fiber displacement sensors have been demonstrated [ 21 , 22 , 23 ].…”