Abstract: The present disclosure provides a neural network-based method for calibration and localization of an indoor inspection robot. The method includes the following steps: presetting positions for N label signal sources capable of transmitting radio frequency (RF) signals; computing an actual path of the robot according to numbers of signal labels received at different moments; computing positional information moved by the robot at a tth moment, and computing a predicted path at the tth moment according to the positional information; establishing an odometry error model with the neural network and training the odometry error model; and inputting the predicted path at the tth moment to a well-trained odometry error model to obtain an optimized predicted path. The present disclosure maximizes the localization accuracy for the indoor robot by minimizing the error of the odometer with the odometry calibration method.

Abstract: The present invention discloses a residual pressure measurement system for a MEMS pressure sensor with an F-P cavity and method thereof, the measurement system includes a low-coherence light source, a 3 dB coupler, a MEMS pressure sensor, an air pressure chamber, a thermostat, a pressure control system, a cavity length demodulator, an acquisition card and a computer. The measurement method comprises: performing cavity length measurement by using the reflecting light by the pressure control system at two temperatures, respectively, so as to calibrate the MEMS pressure sensor and establish a relationship between the absolute phase of a monochromatic frequency and the external pressure; performing linear fitting to the two measurement data to obtain all the external pressure when the cavity length of two measurement data are equal to each other, and substituting the theoretical equation for calculation to obtain the residual pressure under the flat condition of the diaphragm.

Abstract: The present invention discloses a differential COTDR distributed acoustic sensing device based on heterogeneous double-sideband chirped-pulses of the invention, comprising a light source (1), a 1×2 polarization-maintaining optical-fiber coupler (2), a dual Mach-Zehnder electro-optical modulator (3), an arbitrary waveform generator (4), a first low noise microwave amplifier (5), a second low noise microwave amplifier (6), an electro-optical modulator bias control panel (7), a 1×2 optical-fiber coupler (8), an erbium-doped optical-fiber amplifier (9), an optical-fiber filter (10), an optical-fiber circulator (11), a sensing optical fiber (12), a tricyclic polarization controller (13), a 2×2 optical-fiber coupler (14), a balanced photoelectric detector (15), a data acquisition card (16) and a processing unit (17).

Abstract: A Hall sensor trim circuit includes a current source, a transistor, a reference voltage circuit, an amplifier, and a Hall sensor. The transistor includes a first terminal, a second terminal, and a third terminal. The third terminal is coupled to the current source. The amplifier includes an output terminal, a first input terminal, and a second input terminal. The output terminal is coupled to the first terminal of the transistor. The first input terminal is coupled to the second terminal of the transistor. The second input terminal is coupled to the reference voltage circuit. The Hall sensor is coupled to the current source.

Abstract: The present invention discloses a Fiber Bragg Grating demodulation device with a suppressed fluctuation at a variable ambient temperature and a demodulation method. The device comprises a broadband light source (1), an optical attenuator (2), a tunable F-P filter (3), a first optical fiber isolator (41), an erbium-doped optical fiber amplifier (5), an optical fiber first-stage beam splitter (6), a first optical fiber second-stage beam splitter (71), optical fiber circulators (8), FBG sensor arrays (9), a first photoelectric detector array (161), an optical fiber gas cell (10), a second optical fiber second-stage beam splitter (72), an optical fiber F-P etalon (11), a notch filter (12), an optical fiber assisted interferometer (13), a data acquisition card (17) and a processor (18).

Abstract: A Hall sensor trim circuit includes a current source, a transistor, a reference voltage circuit, an amplifier, and a Hall sensor. The transistor includes a first terminal, a second terminal, and a third terminal. The third terminal is coupled to the current source. The amplifier includes an output terminal, a first input terminal, and a second input terminal. The output terminal is coupled to the first terminal of the transistor. The first input terminal is coupled to the second terminal of the transistor. The second input terminal is coupled to the reference voltage circuit. The Hall sensor is coupled to the current source.

Abstract: The present invention discloses a residual pressure measurement system for a MEMS pressure sensor with an F-P cavity and method thereof, the measurement system includes a low-coherence light source, a 3 dB coupler, a MEMS pressure sensor, an air pressure chamber, a thermostat, a pressure control system, a cavity length demodulator, an acquisition card and a computer. The measurement method comprises: performing cavity length measurement by using the reflecting light by the pressure control system at two temperatures, respectively, so as to calibrate the MEMS pressure sensor and establish a relationship between the absolute phase of a monochromatic frequency and the external pressure; performing linear fitting to the two measurement data to obtain all the external pressure when the cavity length of two measurement data are equal to each other, and substituting the theoretical equation for calculation to obtain the residual pressure under the flat condition of the diaphragm.

Abstract: An open drain driver circuit includes an output terminal, an input terminal, a first transistor, a second transistor, and a third transistor. The first transistor includes a first terminal coupled to the output terminal, and a second terminal coupled to a reference voltage source. The second transistor includes a first terminal coupled to a third terminal of the first transistor, a second terminal coupled to a power supply rail, and a third terminal coupled to the reference voltage source. The third transistor includes a first terminal coupled to the input terminal, a second terminal coupled to the reference voltage source, and a third terminal coupled to the third terminal of the first transistor.

Abstract: Fiber optical Fabry-Perot flow test device with local bending diversion structure, having an inlet flange, a test tube and an outlet flange, with both a fiber optical Fabry-Perot pressure sensor at high-pressure-side and a fiber optical Fabry-Perot pressure sensor at low-pressure-side, which are fixedly connected to the test tube through an auxiliary connecting device.

Abstract: The present invention discloses a distributed device for simultaneously measuring strain and temperature based on optical frequency domain reflection, comprising a tunable laser, a 1:99 beam splitter, a main interferometer system, a light source phase monitoring system based on an auxiliary interferometer, an acquisition device and a computer processing unit, wherein the main interferometer system comprises two Mach-Zehnder interferometers, and two optical fibers having different cladding diameters are arranged in parallel as sensing fibers. Due to the difference in temperature and strain coefficients of optical fibers of the same diameter, the temperature and strain values during changing the temperature and strain simultaneously can be obtained by matrix operation, thereby achieving an effect of eliminating cross sensitivity of temperature and strain sensing in optical frequency domain reflection.

Abstract: A distributed optical fiber disturbance positioning system based on the asymmetric dual Mach-Zehnder interference, unlike traditional dual Mach-Zehnder distributed optical fiber disturbance sensing system, the present invention adopts two narrow-bandwidth optical sources (1a, 1b) and adopts corresponding DWDM (3a, 3b) before the detector (4a, 4b) to filter the backscatter noise of the optical fiber, and can solve the problems of having too low SNR due to backscatter influence when the sensing distance is long. The present invention also provides a positioning method for applying the system, which obtains the TFD of the disturbance frame signals by using the time-frequency analysis method based on the short-term average frequency, and takes the points near the point of maximum frequency as the effective signal segment for performing cross-correlation time delay estimation, thus obtaining the delay, and the disturbance position.

Abstract: The present invention discloses a Fiber Bragg Grating demodulation device with a suppressed fluctuation at a variable ambient temperature and a demodulation method. The device comprises a broadband light source (1), an optical attenuator (2), a tunable F-P filter (3), a first optical fiber isolator (41), an erbium-doped optical fiber amplifier (5), an optical fiber first-stage beam splitter (6), a first optical fiber second-stage beam splitter (71), optical fiber circulators (8), FBG sensor arrays (9), a first photoelectric detector array (161), an optical fiber gas cell (10), a second optical fiber second-stage beam splitter (72), an optical fiber F-P etalon (11), a notch filter (12), an optical fiber assisted interferometer (13), a data acquisition card (17) and a processor (18).

Abstract: The present invention discloses an optical fiber laying method by using Archimedes spiral in optical frequency domain reflection, wherein the optical fiber laying method comprises the following steps: performing two measurements continuously via a two-dimensional strain sensing device, and performing cross-correlation operation on the two one-dimensional information of the local distance domain, and obtaining the strain variation of the one-dimensional information corresponding to the two measurements from the obtained cross-correlation information; deriving the two-dimensional angle information and curvature radius information of the plane to be measured corresponding to one-dimensional information in the local distance domain based on Archimedes spiral formula; deriving the position coordinates corresponding to the two-dimensional plane based on the curvature radius information and two-dimensional angle information; corresponding the strain variation of the one-dimensional information to the position coordi

Abstract: The present invention discloses a distributed device for simultaneously measuring strain and temperature based on optical frequency domain reflection, comprising a tunable laser, a 1:99 beam splitter, a main interferometer system, a light source phase monitoring system based on an auxiliary interferometer, an acquisition device and a computer processing unit, wherein the main interferometer system comprises two Mach-Zehnder interferometers, and two optical fibers having different cladding diameters are arranged in parallel as sensing fibers. Due to the difference in temperature and strain coefficients of optical fibers of the same diameter, the temperature and strain values during changing the temperature and strain simultaneously can be obtained by matrix operation, thereby achieving an effect of eliminating cross sensitivity of temperature and strain sensing in optical frequency domain reflection.

Abstract: A distributed optical fiber disturbance positioning system based on the asymmetric dual Mach-Zehnder interference, unlike traditional dual Mach-Zehnder distributed optical fiber disturbance sensing system, the present invention adopts two narrow-bandwidth optical sources (1a, 1b) and adopts corresponding DWDM (3a, 3b) before the detector (4a, 4b) to filter the backscatter noise of the optical fiber, and can solve the problems of having too low SNR due to backscatter influence when the sensing distance is long. The present invention also provides a positioning method for applying the system, which obtains the TFD of the disturbance frame signals by using the time-frequency analysis method based on the short-term average frequency, and takes the points near the point of maximum frequency as the effective signal segment for performing cross-correlation time delay estimation, thus obtaining the delay, and the disturbance position.

Abstract: The present invention discloses a high-resolution polarized low-coherence interference pressure measurement device and method, which comprise a broadband light source (1), an optical fiber coupler (2), an optical fiber Fabry-Perot sensor (3), a collimating lens (4), a polarizer (5), a birefringence wedge (6) having a spatial dip angle, an analyzer (7), a matrix camera (8), and a signal processing unit (9), which are successively provided from an input end to an output end; wherein light emitted from the broadband light source (1) passes through the optical fiber coupler (2) and arrives at the optical fiber Fabry-Perot sensor (3), and returned light emitted from the optical fiber Fabry-Perot sensor (3) is led into a demodulation interferometer; a change in pressure is transformed into a change in length of a Fabry-Perot cavity by the optical fiber Fabry-Perot sensor (3), and different pressures correspond to different lengths of the Fabry-Perot cavity; the collimating lens (4), the polarizer (5), the birefring

Abstract: The present invention discloses a real-time kernel of open CNC systems and a real-time control method of tool-paths. The real-time kernel translates a real-time control of the tool-paths into sending synchronous pulses into the servo drivers in accordance with the control rhythms ?ti (i=1, . . . , n) in the follow-table and achieves the openness of real-time control method and real-time control process. The real-time kernel has the most simple and reliable multi-axis synchronization capability with high-speed and high-precision, and leads to major changes in the field of digital control method. The real-time kernel no need to configure a real-time operating system and a fieldbus, its core function is only to write the control rhythm into the T-division timer, and to send linkage commands into the servo drivers designated by the state-word, therefore its function and architecture are extremely simple and high reliability.

Abstract: The invention discloses a computer-aided numerical control method and system, and changed the computer numerical control (CNC) to the computer-aided numerical control (CANC). Based on discrete geometry and discrete kinematics, the invention is constructed a technical solution of a related data flow file, it is completely solved the optimization of discrete position information and the axis smoothness. The invention is used to manufacture digital control information. Through the three-dimensional graphical interface, therefore completely achieved the software implementation for R&D of CNC technologies and reconfiguration of CNC systems, and is created an open platform for R&D of CNC technologies and CNC systems. The related data flow file, as a computer program product, will be commercializing digital control information, and then will be expediting a new industry namely digital control information manufacture industry.

Abstract: The disclosed method calculates video time density functions based on inter-frame mutual information or other similarity measures. The method includes acquiring a video sequence from memory, computing mutual information or other similarity measures between two consecutive frames of the video sequence, and constructing a video temporal density function based on the mutual information or similarity measures. The method enables fast navigation of the video sequence by performing a temporal quantization of the video time density function to determine a set of quanta. The video sequence can be navigated using the nearest neighbor video frames to the set of quanta. The method enables thumbnail extraction of a video sequence using statistical modeling by performing a temporal quantization of the video time density function to segment video sequence in time domain and using mixture (such as Gaussian mixture and ICA mixture) vector quantization to find the sample frames for each temporal segment.

Abstract: The invention discloses a computer-aided numerical control method and system, and changed the computer numerical control (CNC) to the computer-aided numerical control (CANC). Based on discrete geometry and discrete kinematics, the invention is constructed a technical solution of a related data flow file, it is completely solved the optimization of discrete position information and the axis smoothness. The invention is used to manufacture digital control information. Through the three-dimensional graphical interface, therefore completely achieved the software implementation for R&D of CNC technologies and reconfiguration of CNC systems, and is created an open platform for R&D of CNC technologies and CNC systems. The related data flow file, as a computer program product, will be commercializing digital control information, and then will be expediting a new industry namely digital control information manufacture industry.