40results about How to "Reduce measurement blind spots" patented technology

The invention discloses a distributed optical fiber sensing device based on a chaotic laser coherence method, and a measurement method of the distributed optical fiber sensing device. Chaotic laser light which is emitted from a chaotic laser is divided into detection light and reference light; the detection light is amplified by a light amplifier and then emitted into a sending optical fiber through an optical circulator, and a backward Brillouin scattering light signal is generated in the optical fiber; the Brillouin scattering light signal is amplified by the light amplifier, de-noised by a tunable light filter and then emitted into an optical fiber coupler; the optical length of the reference light is regulated by a variable light delay line, and interferes with the backward Brillouin scattering light signal which is generated by the detection light at different positions in the sensing optical fiber in the optical fiber coupler; an interference beat frequency signal is detected by a photoelectrical detector; and Brillouin gain spectra at different lengths are obtained through a data acquisition device and a signal processing device and then output to a display device, so strain or temperature sensing detection is realized.

The invention discloses an ultrasonic ranging method, belonging to the technical field of electronic measurements. The ultrasonic ranging method comprises the following steps that: an ultrasonic transmitter and a pulse laser are located at a transmitting end, the transmitting end receives a measuring command, subsequently, the pulse laser triggers a beam of pulse laser and the ultrasonic transmitter triggers an ultrasonic wave at the same time, and phase locking is carried out on the triggered ultrasonic wave and an external clock source; an ultrasonic receiver and a photodiode are located at a receiving end, after the photodiode receives the pulse laser, a timer is started, after the ultrasonic receiver acquires the received ultrasonic wave, the timer is stopped to acquire transition time; the transition time multiplies by a revised sound velocity to acquire a rough measurement value of a measured distance; and a phase difference is obtained, a fine measurement part is lambda delta omega/2phi, and an actually measured distance d' is acquired, wherein d'=Nlambda+lambda delta omega/2phi. The ultrasonic ranging method has the advantages that the receiver is easily interfered by the transmitter, a measurement blind zone is greatly reduced, the ultrasonic distance measuring directivity is improved, the distance measuring precision is improved within one ultrasonic wavelength; and the ultrasonic ranging method is particularly suitable for distance measurement in a single station type space orientation and measurement system.

The invention relates to the field of level measurement and provides a system for processing an echo signal of a guided wave type radar level meter taking a single chip as the core. The system is composed of the single chip for controlling the sending and receiving of a pulse signal, a pulse emission circuit, a guided wave rod, an echo signal receiving circuit, an equivalent time sampling circuit, a signal adjusting circuit, a MSP430F5418 single chip system, a liquid crystal display and software. Specific to the material with big relative dielectric constant and the material with small relative dielectric constant, different methods for processing the echo signal are respectively adopted for restraining false echo interference, confirming and correcting a peak value of a real echo, and then fitting or interpolating nominal data, thereby realizing the level measurement.

The invention provides an electromagnetic ultrasonic thickness gauge for measuring the thickness of a specimen in a variety of abominable environments and a measurement method thereof. The electromagnetic ultrasonic thickness gauge is composed of a microcontroller, a transmitting circuit, an electromagnetic ultrasonic probe, a receiving switch, a conditioning circuit, an echo processing system, a display system and a keyboard, wherein the microcontroller is connected with the transmitting circuit which is connected with the electromagnetic ultrasonic probe, the electromagnetic ultrasonic probe is connected with the receiving switch which is connected with the microcontroller and the conditioning circuit, the conditioning circuit is connected with the echo processing system, and the display system is connected with the microcontroller which is connected with the keyboard. The electromagnetic ultrasonic thickness gauge uses a normal-incidence body wave to measure the thickness and achieves the measurement accuracy which is twice as high as that of piezoelectric ultrasonic thickness gauge at the same frequency. The electromagnetic ultrasonic probe which adopts a pulse electromagnet to offer magnetic field can effectively detect various metallic specimens; as a transceiving separated coil is used for exciting and detecting ultrasonic waves, the blind area for the measurement is small and the measurement thickness can be in a range from 3mm to 200mm.

The invention relates to a cable fault simulation and location system, which comprises a cable fault simulation case, an electrode mounting plate arranged in the cable fault simulation case, three incoming line electrodes and three outgoing line electrodes, wherein the three incoming line electrodes are connected with a three-phase wire core in an incoming line cable respectively; the three outgoing line electrodes are connected with a three-phase wire core in an outgoing line cable respectively; a resistance box for simulating disconnection faults, low-resistance faults, high-resistance faults and flashover faults between the incoming line electrodes and the outgoing line electrodes is arranged in the cable fault simulation case; the tail end of the outgoing line cable connected with the outgoing line electrodes is provided with a high-voltage cable terminal; and the high-voltage cable terminal is used for connecting a cable fault location detector. The cable fault location detector comprises a central control unit, an impulse transmission circuit for transmitting impulse signals to a tested cable, a reflection receiving circuit for receiving reflected signals from the tested cable and a high-speed data acquisition circuit, wherein an output end of the reflection receiving circuit is connected with an input end of the high-speed data acquisition circuit.

Disclosed is a channel depth measuring method based on a chaotic laser device and a correlative method thereof. The depth of a channel in a shoal water area can be measured on the basis of the chaotic laser device. The method includes on a channel water surface carrier, allowing the chaotic laser device to emit probing light and reference light, allowing the probing light to emit to the water bottom of the channel perpendicularly, collecting reflected probing light signals through a telescope, and converting the probing light signals into electrical signals; converting the reference light into electrical signals through a photoelectric detector, after storing two paths of electrical signals, performing correlation calculation, acquiring the time for light signals flying for a round trip in the channel water, and acquiring the channel depth accordingly. By the aid of the method, the conflict between the distance resolution and measuring depth according to the existing laser radar technology for measuring the channel depth is solved, the distance resolution unit can be centimeter, and the advantage of interference resistance is provided.

The invention relates to a double fiber array sensor for measuring gas phase distribution parameters of gas-liquid two-phase flow, comprising eight identical dual-fiber probe sensors distributed at three annular locations within the measurement channel. The first ring comprises a 1-way dual-fiber probe sensor and is located in the center of the pipe. The second ring comprises a 3-way dual-fiber probe sensor with an equilateral triangle evenly distributed over a small circumference. The third ring comprises a 4-way dual fiber probe sensor uniformly distributed in a square shape. The radius of the small circle where the second ring sensor is located is equal to half of the radius of the circle in the third ring sensor and one-third of the radius of the measuring pipe. Each of the dual-fiberprobe sensors comprises a metal sleeve and a long and a short and a long identical fiber probes extending from the metal sleeve. The long probe is an upstream fiber probe and the short probe is a downstream fiber probe. The gas-liquid two-phase flow gas distribution parameter measurement method for double fiber array sensor simultaneously provides a gas-liquid two-phase flow distribution parametermeasurement method realized by the array sensor.

The invention discloses an ultrasonic sensor including a housing and a piezoelectric crystal plate disposed in the housing. A pedestal is mounted on one end of the housing. One side of the piezoelectric crystal plate facing towards the pedestal is provided with flexible adhesive fixedly while the other side is provided with a matching layer fixedly. The paste-shaped matching layer subjected to stirring is fixed on the piezoelectric crystal plate through adhesive dispensing or adhesive brush coating and the matching layer is in clearance-free bonding with the surface of the piezoelectric crystal plate. Then through heating, the material of the matching layer is cured fully, so that the matching layer and the piezoelectric crystal plate are integrated together. According to the invention, residual oscillation is reduced substantially and measurement dead zone is reduced. Through the method of bonding the material of the matching layer and the crystal plate integrally, the echo flexibility is improved. The ultrasonic sensor is simple in structure, low in cost increase and substantially improved in performance.

The invention discloses a flow rate measuring device based on an ultrasonic reflecting signal. The flow rate measuring device comprises a measuring rod, wherein a first probe with ultrasonic transmitting and receiving functions is arranged at the bottom end of the measuring rod; a first reflecting probe and a second reflecting probe are arranged around the first probe, and are connected with the measuring rod through connecting rods; the first probe, the first reflecting probe and the second reflecting probe are respectively connected with a signal processing unit. The flow rate measuring device based on the ultrasonic reflecting signal has the advantages that the plane two-dimensional flow rate is realized, the measuring blind area is small, and the like; a signal detection circuit only needs to detect the pulse reflecting time, a signal processing circuit is simple, and the instrument cost is greatly reduced in comparison with that of the ultrasonic Doppler measuring instrument.

The invention discloses a control system for the blind area of ​​an ultrasonic transducer, which includes a double-sensor ultrasonic transducer, a controller and a reverse boost circuit; the double-sensor ultrasonic ring energy device includes an ultrasonic transmitting sensor, an ultrasonic receiving sensor, and an ultrasonic transmitting sensor Placed in the shell of the transmitting sensor, the ultrasonic receiving sensor is placed in the shell of the receiving sensor, and the shell of the transmitting sensor and the shell of the receiving sensor are connected together with a connecting piece; The boost circuit adjusts the driving voltage output to the ultrasonic transmitting sensor according to the reverse boost amplitude control signal; the reverse boost amplitude control signal is used to control the driving voltage of the ultrasonic transmitting sensor to change in the same direction as the distance to be measured. The invention has the advantages of small measurement blind area, wide measurement range and high detection precision.

The invention requests to protect a pulse laser ranging error compensation method based on GABP, and the method comprises the following steps: 1, designing a hardware circuit which is used for detecting an optical signal, converting the optical signal into an analog electric signal, and converting the analog signal into a digital signal through employing a fixed threshold value; inputting the digital signal into a time measurement unit, and measuring the pulse width of the echo signal and an original flight time parameter value; 2, setting different target objects, and obtaining the parametervalues of the pulse width and flight time error of the echo signal in the data obtaining mode in the step 1; the data analysis software obtains correction curve network parameters by using a GABP regression analysis method; 3, writing the optimized neural network parameters obtained in the step 2 into a microprocessor; and carrying out an actual ranging test in a range of 60-600cm, and verifying the ranging precision of the range finder based on the GABP compensation algorithm.

The invention relates to the field of electronic sensors, in particular to a small dead zone ultrasonic wave sensor. The small dead zone ultrasonic wave sensor comprises a main control chip, a temperature measuring element, an emission circuit and a receiving circuit, wherein the temperature measuring element, the emission circuit and the receiving circuit are each connected with the main control chip; the small dead zone ultrasonic wave sensor is simple in structure; the range of a dead zone of a system is 5 cm; when the dead zone of the system ranges from 10 cm to 60 cm, an error is smaller and the measuring error is 0; when the dead zone of the system ranges from 60 cm to 500 cm, the error is larger and the error is 1-3 cm; due to the influence of the mass of the ultrasonic wave sensor, the system can only measure distance within 5 cm; meanwhile with the increasing of measuring distance, the error is increased gradually, the error can be basically controlled less than 2%, and the precision is higher.

The invention provides a tetra-nocular camera positioning device. The device comprises a left upper camera, a left lower camera, a right upper camera and a right lower camera, wherein an upper binocular camera is formed by the left upper camera and the right upper camera, and a lower binocular camera is formed by the left lower camera and the right lower camera; and the upper binocular camera faces upwards, while the lower binocular camera faces downwards. Compared with the prior art, the tetra-nocular camera positioning device has the advantages that the tetra-nocular camera is formed by four cameras, and the pitching angle and camera interval are accurately designed, so that the measurement blind zone is as small as possible while the longitudinal vision of the tetra-nocular camera is enlarged, the shooting range of the tetra-nocular camera is greatly increased, and the experience effect is optimized.