A system and method for dynamically calibrating a distributed fiber optic sensing system is disclosed. The calibration system includes a light source for generating pulses of coherent light, an optical fiber arranged at least partly in a ground soil region to guide the light and a photo detector for detecting scattered light returning from the optical fiber in dependence of time. The method includes obtaining information from which a temporal change of an acoustic transfer characteristic of the ground soil region is derivable and calibrating a distributed acoustic sensing system based on the changed acoustic transfer characteristic.

An optical module applied to a fiber optic sensor. The optical module comprises a housing (11), a circuit board (12) installed in the housing (11) and a digital-to-analog conversion circuit (121), a light source control circuit (122) and an electro-optic conversion unit (123) installed on the circuit board (12) and sequentially and electrically connected. Also installed on the circuit board (12) and sequentially and electrically connected are an opto-electronic conversion unit (124), a signal filter amplification circuit (125) and an analog-to-digital conversion circuit (126), and a circuit interface (127) installed on the circuit board (12) is separately and electrically connected to the digital-to-analog conversion circuit (121) and the analog-to-digital conversion circuit (126) respectively. The optical module enables control of a fiber optic sensor and modularization of acquisition circuits, thus providing an application system for a fiber optic sensor with a simple and low-cost structure.

A measuring system for determining a torsion of a rotor blade, comprising a reference shaft to be arranged in the rotor blade in the longitudinal direction of the blade, at least one support for the reference shaft, for freely bearing the reference shaft in the rotor blade, so that the rotor blade can twist freely about the reference shaft, so that the reference shaft does not twist when there is twisting of the rotor blade, at least one rotary sensor, arranged on the reference shaft, for detecting a twisting of the rotor blade about the reference shaft in the region of the rotary sensor, the rotary sensor outputting a rotational angle describing the twisting of the rotor blade in relation to the reference shaft, or some other corresponding variable. A method for determining a torsion of a rotor blade, a corresponding rotor blade, a method for arranging a measuring system in a rotor blade and a corresponding wind power installation with a rotor blade and also or alternatively a measuring system.

Apparatus and associated methods relate to a system for interfacing with an optically-powered sensor. The system includes an optical emitter configured to emit a beam of optical energy so as to provide operating power for the optically-powered sensor. The system includes an optical detector configured to detect a time sequence of optical pulses generated by the optically-powered sensor, the time sequence of pulses modulated between first and second optical power levels. The system includes a parameter extractor configured to determine a value of a sensed parameter based on the time sequence of optical pulses detected by the optical detector. The system also includes a power controller configured to control power level of the emitted beam of optical energy based on the first and/or second optical power levels detected by the optical detector.

A new method of gathering data real time during production or simulation tests using a gravity deployed tool, referred to as a fiber-line intervention tool (FLI or FLIT) to monitor bottom-hole pressure and temperature for well testing including the testing of adjacent wells is provided. In an embodiment, the tool is configured to include a housing, spooled fiber-line, sensors such as pressure and temperature sensors, and connections between the fiber-line and sensors such that measurement information from the sensors can be sent to the surface in real time over the fiber-line. As the housing is deployed into a well, the fiber-line can unwind, thereby providing a communication pathway from below the surface to above the surface. In an embodiment the housing can be deployed through a wellhead and down the wellbore. In an embodiment, the housing can be made of a soluble material.

The present invention relates to a signal processing device for monitoring states of wind-power turbine blades and a method thereof, the signal processing device comprising: an optical fiber sensor unit for sensing moment of rotation of three blades so as to output the moment of rotation as blade signals; a signal transformation unit for converting three blade signals into two fore-ape signals; a rotation information input unit for sensing rotation information of the blades; a rotation speed estimation unit for estimating a rotation speed of the blades on the basis of the rotation information; a state determination unit which removes rotation components from the fore-ape signals and determines whether an operation of a blade is abnormal; and an output unit for outputting the determination result. According to the present invention, two fore-ape signals which are simpler than three blade signals can be processed such that an efficient signal analysis is enabled and the efficiency of determining a state of blades is improved, thereby efficiently managing and maintaining the blades.

A system includes a first part and a second part, the second part being movable relative to the first part, the first part having an optical waveguide that radiates light on the side, the second part at least one sensor system for detecting the light intensity.

To provide a confocal displacement sensor capable of easily and accurately measuring displacement of a measurement object. Light having a chromatic aberration is converged by a lens unit 220 and irradiated on a measurement object S from a measurement head 200. Light having a wavelength reflected while focusing on the surface of the measurement object S passes through the optical fiber 314 in the measurement head 200. The light passed through the optical fiber 314 is guided to a spectral section 130 in a processing device 100 and spectrally dispersed. In the processing device 100, the light spectrally dispersed by the spectral section 130 is received by a light receiving section 140. A light reception signal output from the light receiving section 140 is acquired by a control section 152. The control section 152 measures displacement on the basis of the acquired light reception signal and gives the light reception signal to a PC 600 on the outside. A CPU 601 of the PC 600 causes a display section 700 to display, as change information, a change from a light reception signal acquired at a point in time before a present point in time to a light reception signal acquired at the present point in time.

Particle detection device comprising a support, a platform for receiving particles, four beams suspending the platform from the support, such that the platform can be made to vibrate, means for making said platform vibrate at a resonance frequency, means for detecting the displacement of the platform in a direction of displacement. Each beam has a length I, a width L and a thickness e and the platform has a dimension in the direction of displacement of the platform and in which in a device with out of plane mode I?10?L and the dimension of each beam in the direction of displacement of the platform is at least 10 times smaller than the dimension of the platform in the direction of displacement.

A method, system, and apparatus are disclosed for a ruggedized photonic crystal (PC) sensor packaging. In particular, the present disclosure teaches a ruggedized packaging for a photonic crystal sensor that includes of a hermetic-seal high-temperature jacket and a ferrule that eliminate the exposure of the optical fiber as well as the critical part of the photonic crystal sensor to harsh environments. The disclosed packaging methods enable photonic crystal based sensors to operate in challenging environments where adverse environmental conditions, such as electromagnetic interference (EMI), corrosive fluids, large temperature variations, and strong mechanical vibrations, currently exclude the use of traditional sensor technologies.