83results about How to "Eliminate detection blind spots" patented technology

The invention discloses a networking navigation radar target tracking system based on data fusion. The system comprises at least one radar front end, at least one radar terminal and an Ethernet. The radar front end and the radar terminal are in bidirectional data transmission through the Ethernet. The radar front end comprises an antenna, a transceiver, a data acquisition module, a signal preprocessor module and a control command processing module. The radar terminal comprises a display unit, a signal processing unit and a control unit. The transceiver generates radio-frequency pulses which are radiated to the space through an antenna. The system belongs to a trace point serial processing centralized data fusion structure, has the features of high fusion precision and small system time delay, and meanwhile, has the advantages of eliminating detection blind areas, improving detection probability and improving tracking performance. After the terminal carries out data fusion and comprehensive optimization processing on the data of the plurality of front ends, the problem of blind area of the single radar due to antenna erection location can be effectively solved, marine target detection and tracking accuracy performance is improved, and navigation safety is guaranteed.

The invention relates to an integrated bridge detection system based on unmanned aerial vehicles and belongs to the technical field of unmanned aerial vehicle bridge detection. The system comprises abridge modeling unmanned aerial vehicle A, a bridge surface data collection unmanned aerial vehicle B and a ground integrated information processing control system. The ground integrated information processing control system comprises a 3D coordinate modeling system, an unmanned aerial vehicle cruising route planning system, a bridge deck defect detection and marking system, and a bridge quality detection report generation system. The unmanned aerial vehicle A is used for photographing a detected bridge and a surrounding terrain environment. The 3D coordinate modeling system is used for establishing 3D coordinate models of a bridge body and the surrounding terrain environment. The unmanned aerial vehicle cruising route planning system is used for planning a cruising route of the unmanned aerial vehicle B. The bridge deck defect detection and marking system is used for detecting defects of corresponding locations of a bridge deck, computing defect level indexes and marking the defect level indexes in the model. According to the system, full automation of a bridge detection process is realized, detection efficiency is greatly improved, and detection quality is improved.

The invention discloses a mobile robot, and relates to the technical field of robots. The mobile robot comprises a body, and wheels, a motor, a first image acquisition device, a photoelectric sensor, a supplement light and a processor which are arranged on the body, wherein the wheels are driven by the motor to drive the mobile robot to move on the ground; the first image acquisition device is used for acquiring environment images; the processor is used for performing data processing on the environment images through a preset method, controlling the motor to perform obstacle avoidance action when identifying obstacles in the environment images, eliminating close-distance detection dead zones, and improving user experience; the photoelectric sensor is used for detecting environment illumination intensity; and the processor is further used for controlling the supplement light to give out light when environment illumination intensity is smaller than or equal to a preset threshold value, so that illumination intensity in the visual range of the first image acquisition device is improved, the first image acquisition device conveniently shoots enough bright environment images, and detection success rate is increased.

The invention discloses a fiber distributed sensing method and device based on multi-wavelength double light pulses, and the method comprises the following steps: S1, generating multi-wavelength double light pulses and injecting the multi-wavelength double light pulses into a sensing fiber, each of the multi-wavelength double light pulses comprising a plurality of wavelength components; S2. obtaining a Rayleigh optical signal in the sensing fiber, and the interference light intensity of the sensing channel corresponding to the Rayleigh optical signal; S3, calculating the interference light intensity to obtain phase information of the Rayleigh optical signal, thereby obtaining information of the signal sensed by the sensing fiber. The method and device use the [phi]-OTDR technology which can be used for the PGC-based phase demodulation technology, reduces the influence of the Rayleigh fiber signal intensity attenuation on the measurement noise without increasing signal processing workload, and eliminates the detection dead zone caused by a high phase noise.

The invention discloses a bidirectional active power disturbance island detection method. The method comprises the following steps of: adding the disturbance quantity of positive and negative delta I into grid-connected current; calculating an absolute value of difference between Uold and Unew; comparing the absolute value of the difference between the Uold and the Unew with a set maximum permissible value of voltage difference between the Uold and the Unew; and if frequency that the absolute value of the difference between the Uold and the Unew is continuously greater than the set maximum permissible value of the voltage difference between the Uold and the Unew is greater than or equal to a set value, detecting an island phenomenon. By adoption of the bidirectional active power disturbance island detection method, the island phenomenon can be timely and effectively detected, and harmonic wave is slightly introduced to a common coupling point.

The invention belongs to the technical field of agricultural seed particle sensing and detection, and in particular relates to a thin-surface laser medium and small particle size seed flow sensing device. The sensing device includes: a seed inlet, a seed introduction tube, a laser emitting module, a photoelectric receiver, a seed outlet, a signal collection system, a power supply unit and a packaging shell. The seed flow falling from the seeding port of the seed meter enters the detection area through the seeding port, blocking a small part of the optical path of the thin-surface laser irradiated to the photoelectric receiver, causing the output voltage signal to be disturbed, and processed by the signal acquisition system to thereby Digitize the seed stream. The sensing device provided by the present invention has higher detection accuracy and excellent economical practicability, and can improve the seeding performance (sowing rate, rowing rate, etc.) frequency, missed broadcast, qualified index, etc.) to provide technical support for detection.

The invention discloses a self-coupled probe mechanism based on parallel passive-type fine adjustment structure, which belongs to the technical field of supersonic wave automatic flaw detection. The self-coupled probe mechanism comprises an installing plate, parallel springs, a connection rack, a probe shell, a S pair, a coupling spring, and a multi-focal probe; the installing plate and a flaw detection host are connected; the parallel spring and the S pair are placed between the installing plate and the connection rack; the connection rack is connected with the probe shell by a screw, and is connected with the installing plate by the S pair, and a set of parallel springs are cooperated; the multi-focal probe with a square cross section is inserted in the square probe shell, the multi-focal probe and the square probe shell enable sliding fit, and the coupling spring is arranged at tail of the probe. While flaw detection is carried out, the probe and a wheel tread are contacted for pressing, movement and swing can be carried out under common effect of the parallel springs, the S pair, and the coupling spring, when the shape of the wheel tread is changed, the probe position and pose is passively adjusted with real time, good coupling can be maximally guaranteed. In addition, an angle-changeable wafer arranged in the probe realize multiple focal length, so that flaw detection on near surface of wheel tread and deeper area can be simultaneously carried out.

The invention, which belongs to the technical field of photovoltaic generating and distributed generating inverter control, relates to an MPPT-based island detection method. A voltage amplitude value of a grid-connected point is affected by disturbance on MPPT; whether an island occurs is determined based on the voltage amplitude value of the grid-connected point; and disturbance on the MPPT is carried out by increasing a duty ratio D of a boost circuit, so that an objective of reduction of the photovoltaic output voltage and power can be achieved. In an off-grid state, with reduction of the photovoltaic output power, the voltage of the grid-connected point is reduced; and when the voltage of the grid-connected point deviates from a normal range, an island state is determined. According to the invention, with fully consideration of an active matching situation of a local load and a distributed photovoltaic generating system, the parameter setting becomes reasonable, the blind detection area is eliminated, the disturbance period setting becomes reasonable, the power loss is reduced, and the influence on the electric energy quality is affected.

The invention relates to a distributed power supply active islanding detection device and method, which belongs to the technical field of intelligent power grids. According to the invention, a neutral point of an isolation transformer high voltage side winding of an inverter in a power grid system is connected in series with a grounding transformer; the secondary side of the grounding transformer is connected with a low-frequency alternating current power supply; the alternating current power supply injects a certain amount of low-frequency voltage and low-frequency current into the neutral point in the power grid system through the grounding transformer; the voltage and the current of a measuring circuit composed of the grounding transformer and the alternating current power supply is measured in real time; and according to variation features of voltage and current measurement values before and after an islanding effect, an absolute value amplitude comparison principle is used to carry out islanding detection. According to islanding detection provided by the invention, the alternating current power supply is injected into the neutral point of the isolation transformer high voltage side winding of the inverter in the power grid; detection blind spots are eliminated; the impact of power quality on the power grid is reduced; and islanding detection can be quickly and accurately carried out.

The invention discloses an electromagnetic ultrasonic transducer of an end portion-free detection blind area. The electromagnetic ultrasonic transducer comprises a magnetic upper shell and a non-magnetic lower shell, and a traction handle used for holding and operating; the lower shell is provided with a high frequency coil and two permanent magnets with a same magnetic pole direction, the two permanent magnets respectively have a sector-shaped structure with wide top and narrow bottom, the high frequency coil gets around the lower side of one of the permanent magnets to form an excitation end; the upper shell fits with the upper portion of the lower shell to make the two permanent magnets be adsorbed on the upper shell in a mutual parallel manner; and two sides of the lower portion of the lower shell are symmetrically provided with a plurality of rigid wheels. The electromagnetic ultrasonic transducer of the end portion-free detection blind area, adopting the above design, has the advantages of increasing of the intensity and the signal to noise ratio of a magnetic field and a signal, convenient use and operate, realization of convenient replacement of the coil, protection of the coil from being damaged, elimination of the detection blind area, and effective protection of the surface of a workpiece.

The invention discloses an acoustic screen method of a multi-path channel. The method of the invention comprises the following steps: a sound velocity meter measures the acoustic velocity of water; a horizontal receiving array receives a radiation signal of a plurality of point sources in a sound field, amplifies the filtration and then carries out the data acquisition; the weight obtained by realizing the sound focusing of a spherical sound field array is the optimum focusing weight; based on the optimum focusing weight, shielding factors are increased to obtain the optimum focusing shielding weight; the output waveform is obtained by inverse Fourier transform and output power also can be obtained by frequency domain integral; the following coherent processing is carried out or the power after sound shielding and focusing is output. The invention is based on the principle and the method of sound shielding, applicable to multi-point source coherent interference in the water acoustics engineering; and in the engineering, the invention can adopt the horizontal array, thus being more applicable to being loaded on motion platform or being fixed at sea bottom.

The invention discloses a tunnel lining state detection device which includes a mobile work platform (40). The lower end of a mechanical bent arm (10) is connected with the work platform (40) througha rotating gear shaft (11). The mechanical bent arm (10) is curved and telescopic. The rotating gear shaft (11) is connected with a first drive mechanism which can drive the mechanical bent arm (10) to swing around the rotating gear shaft (11) as an axis. A radar antenna support trolley (30) is disposed on a slip rope (20). The radar antenna support trolley (30) can move along the slip rope (20).A geological radar antenna (31) is fixed on the radar antenna support trolley (30). The mechanical bent arm is designed on the tunnel lining state detection device, and the design idea of linear lifting of a mechanical arm is changed. The detection speed is greatly improved. The response is quick. The motion range is very small. There is basically no obstacle avoidance behavior. The detection blind area is completely eliminated. The device has stable performance.

The invention discloses an island detection method for a photovoltaic grid-connected inverter based on comprehensive frequency and phase information. Active frequency shifting detection can be realized based on frequency and phase information of the last period; the main principle is as follows: in the k zero-crossing point of an end voltage, the power grid voltage frequency of the last period is measured firstly; then an active frequency disturbance value f[k] is set to be equal to f[k-1] plus or minus <delta> f according to the frequency; meanwhile, a phase angle, which is as shown in the specification, is also changed according to the frequency f[k-1] of the inverter in the last period; island detection hardware performs active drifting on the frequency and phase of the power grid voltage and then the processed power grid voltage is used as the set frequency of the grid-connected inverter; in addition, the grid-connected current is reset in voltage zero-crossing; in grid-connection, the system frequency detected by the island detection hardware in each time is unchanged; in an off-network state, the system frequency detected in each time can rapidly achieve upper limit and lower limit of protection to perform protection actions so as to realize an anti-island function; and by virtue of the island detection method disclosed by the invention, non-detection regions in the conditions that the load is close to photovoltaic power generation power and the load is less than the photovoltaic power generation power can be obviously reduced.

The invention relates to a cable anti-theft device and a method thereof and belongs to the field of cable theft prevention. A cable comprises a cable core, a protective layer located outside the cable core and a sheath layer covering the protective layer. The device comprises an alarm unit, a control center, a line breakage detection unit and a ranging unit; the control center outputs a signal to the alarm unit and the ranging unit; the input end of the line breakage detection unit is connected with the ranging unit; the output end of the line breakage detection unit is connected with the control center. The line breakage detection unit detects trace current in a circuit under detection, through volt-ampere characteristics of a triode and through the control center, thereby judging line breakage of a transmission line; once line breakage occurs, a ranging alarm is given out fast, and thus, economic loss is reduced and mistaken alarming of the existing detection circuit is avoided; the circuit is simple, and the problem that the prior cable anti-theft device is high in false alarm rate is solved.

The invention provides a field static vehicle weighing detecting method of a dynamic road vehicle automatic weighing instrument. A technical scheme of the invention comprises the following steps: the dynamic road vehicle automatic weighing instrument is set in a dynamic weighing mode; each wheel axle of a reference vehicle passes a bearer of the dynamic road vehicle automatic weighing instrument in turn; each wheel axle stops while running to the centre of the bearer; the wheel axles are dynamically weighed one by one to obtain axle load values; and finally the axle load values can be accumulated to obtain total vehicle weight and indication error of the following different reference vehicles. The field static vehicle weighing detecting method of the dynamic road vehicle automatic weighing instrument, provided by the invention, has the advantages that influences on the reference vehicle from outside factors like speed variation (acceleration and deceleration), larger speed (too short sampling time), deviation from a central position (passing in a curve and passing from one side), levelness of road surfaces on two ends of the bearer and the like during passing the bearer are effectively reduced, a metering detecting precision is increased and an accuracy of the weighing instrument is assured on the premise of no change of the working mode of the dynamic road vehicle automatic weighting instrument and the structure of the reference vehicle.

The invention discloses a fire alarm robot for transformer substations and inflammable places. The fire alarm robot comprises a transmission system, direct-current motor driving modules, flame sensors, smoke sensors, tracking modules, an ultrasonic module, an active buzzer module, a communication module, a single-chip microcomputer, a remote control module, a power source system and a fixing plate, wherein the direct-current motor driving modules, the flame sensors, the smoke sensors, the tracking modules, the ultrasonic module, the active buzzer module, the communication module, the remote control module and the power source system are connected with the single-chip microcomputer. The fire alarm robot has the advantages that accuracy and instantaneity of fire alarm are improved, detection blind zones are eliminated, time for fire alarm is shortened, fire damage is effectively reduced, manpower inspection tour is substituted and cost is reduced.

The invention provides an X-ray detector applied to impurity detection. The detector comprises a conveyor line, double light source X-ray scanning equipment and information processing equipment, wherein the conveyor line is used for conveying detected articles; the double light source X-ray scanning equipment is used for generating two X rays for scanning the detected articles; the two X rays form a ray included angle; and the information processing equipment is connected with the double light source X-ray scanning equipment and is used for processing the information obtained after scanning of the double light source X-ray scanning equipment to form images. The X-ray detector based on double light sources can generate X-ray double light sources so as to project the detected articles in two directions to form two complementary X-ray detecting images, thus solving the intrinsic blind zone problem of the single light source detectors and improving the impurity detection accuracy rate.

The invention provides a photomask detection method. The photomask detection method comprises the following steps: providing a control wafer, and transferring the patterns of the photomask to be detected to the control wafer; performing primary defect scanning on the control wafer; rotating the control wafer at 90 degrees, and then performing secondary defect scanning. According to the photomask detection method provided by the invention, the patterns of the photomask to be detected are transferred to the control wafer, and the control wafer is scanned in two perpendicular directions to eliminate detection blind points of scanning equipment, so that defects can be comprehensively defected by the scanning equipment.

The invention discloses an infrared multipoint touch television computer all-in-one machine, which consists of a touch screen, a display, a computer module and a television module, wherein the touch screen is connected with the computer module through a universal serial bus (USB) interface and is used for communication through a USB data line; audio/video data are transmitted between the computer module and the television module through audio/video connecting lines; the touch screen is provided with an infrared emission array and a corresponding infrared receiving array; the infrared emission array consists of a plurality of infrared emission tubes; and each infrared emission tube consists of an emission tube core and a lead. The machine is characterized in that: a small-sized convex lens is arranged in front of a luminous surface of the emission tube core in each infrared emission tube; and the emission tube core is positioned at the focus point of the convex lens. The infrared emission tubes capable of converging infrared rays emitted by the infrared emission tubes are adopted, so that the emitted energy loss of the infrared rays is effectively reduced, and the size of the touch screen of the infrared multipoint touch television computer all-in-one machine can be increased.

The embodiment of the invention discloses a blind area early warning radar and a blind area early warning system, the blind area early warning radar comprises a first detection assembly and a second detection assembly, the first detection assembly is used for emitting a first electromagnetic wave, the first electromagnetic wave has a first detection viewing angle, and the second detection assemblyis used for emitting a second electromagnetic wave, the second electromagnetic wave has a second detection viewing angle. Two adjacent sides of the first electromagnetic wave and the second electromagnetic wave intersect or coincide, and a detection field angle formed by superposing the first detection viewing angle and the second detection viewing angle is larger than or equal to 180 degrees. Bymeans of the arrangement, the blind area early warning radar can conduct detection with the field angle of 180 degrees, the detection blind area is eliminated, and the safety of automobile driving isimproved.