Abstract: Disclosed is a device and method for distributed detection of straightness of a working face of a scraper conveyor based on optical fiber sensing. The device includes a broadband light source, a first optical fiber circulator array, a second optical fiber circulator array, a collimator array, a reflecting film array, a third optical fiber circulator array, and an optical path analyzer. During transmission of light emitted from the broadband light source, the light with different wavelengths is separated via several optical gratings etched on a single-mode optical fiber (SMF), and reaches reflecting films adhered to the working face of the scraper conveyor through first optical fiber circulators, second optical fiber circulators, and collimators. The light with the different wavelengths is then reflected back from the reflecting films, enters the SMF through third optical fiber circulators, and finally enters the optical path analyzer.

Abstract: Disclosed is a device and method for distributed detection of straightness of a working face of a scraper conveyor based on optical fiber sensing. The device includes a broadband light source, a first optical fiber circulator array, a second optical fiber circulator array, a collimator array, a reflecting film array, a third optical fiber circulator array, and an optical path analyzer. During transmission of light emitted from the broadband light source, the light with different wavelengths is separated via several optical gratings etched on a single-mode optical fiber (SMF), and reaches reflecting films adhered to the working face of the scraper conveyor through first optical fiber circulators, second optical fiber circulators, and collimators. The light with the different wavelengths is then reflected back from the reflecting films, enters the SMF through third optical fiber circulators, and finally enters the optical path analyzer.

Abstract: A device and method for detecting an angle of a shearer rocker arm based on optical fiber sensing. The device includes an optical system and a mechanical system. The optical system includes a broadband light source, a polarizer, collimating lenses, a gradient-rotation media plate, a polarization beam splitter, and a data processing module. The mechanical system includes a connecting base, connecting rods, a slider, a bracket, and a sensor housing. When the shearer operates, the rocker arm converts rotation angle information to linear displacement related to a gradient refractive index by using a connecting rod mechanism, and a position on the gradient-rotation media plate through which linearly polarized light produced by the optical system passes also changes. Due to an optical rotation effect, corresponding rotation angles of a plane of polarization that are formed after the light passing through the gradient-rotation media plate also vary.

Abstract: A device and method for detecting an angle of a shearer rocker arm based on optical fiber sensing. The device includes an optical system and a mechanical system. The optical system includes a broadband light source, a polarizer, collimating lenses, a gradient-rotation media plate, a polarization beam splitter, and a data processing module. The mechanical system includes a connecting base, connecting rods, a slider, a bracket, and a sensor housing. When the shearer operates, the rocker arm converts rotation angle information to linear displacement related to a gradient refractive index by using a connecting rod mechanism, and a position on the gradient-rotation media plate through which linearly polarized light produced by the optical system passes also changes. Due to an optical rotation effect, corresponding rotation angles of a plane of polarization that are formed after the light passing through the gradient-rotation media plate also vary.

Abstract: A method for detecting an insulation damage location in a reflux rail of a subway/coal mine and a transition resistance thereof includes the following steps: connecting a reflux rail to a negative electrode of a substation, selecting a location at a connecting point as a reference location, and mounting a potential detection apparatus at the reference location; mounting a travel distance detection apparatus and a traction current detection apparatus on a locomotive, traveling, by the locomotive, to the substation along the reflux rail, where the three detection apparatuses send respectively recorded data to a control unit; and determining, by the control unit, a potential jump from received potential data and a corresponding jump time, and determining a running distance of the locomotive at a jump moment and a total running length of the locomotive, so as to determine a ground insulation damage location.

Abstract: A method for detecting an insulation damage location in a reflux rail of a subway/coal mine and a transition resistance thereof includes the following steps: connecting a reflux rail to a negative electrode of a substation, selecting a location at a connecting point as a reference location, and mounting a potential detection apparatus at the reference location; mounting a travel distance detection apparatus and a traction current detection apparatus on a locomotive, traveling, by the locomotive, to the substation along the reflux rail, where the three detection apparatuses send respectively recorded data to a control unit; and determining, by the control unit, a potential jump from received potential data and a corresponding jump time, and determining a running distance of the locomotive at a jump moment and a total running length of the locomotive, so as to determine a ground insulation damage location.

Abstract: A synchronous monitoring device and a method for radial and axial vibration of a shearer drum. The monitoring device includes a laser, a first optical fiber coupler, an optical isolator, a second optical fiber coupler, a third optical fiber coupler, an optical fiber collimator, a first photodetector, a second photodetector, a first signal processing module, and a second signal processing module which are disposed on a shearer ranging arm, as well as a reflective coating disposed on a shearer drum. By measuring a phase difference between original light and reflected light, axial vibration of the shearer drum is monitored, and by measuring an intensity difference between original light and reflected light, radial vibration of the shearer drum is monitored.

Abstract: A synchronous monitoring device and a method for radial and axial vibration of a shearer drum. The monitoring device includes a laser, a first optical fiber coupler, an optical isolator, a second optical fiber coupler, a third optical fiber coupler, an optical fiber collimator, a first photodetector, a second photodetector, a first signal processing module, and a second signal processing module which are disposed on a shearer ranging arm, as well as a reflective coating disposed on a shearer drum. By measuring a phase difference between original light and reflected light, axial vibration of the shearer drum is monitored, and by measuring an intensity difference between original light and reflected light, radial vibration of the shearer drum is monitored.