117 results about "Time of flight" patented technology

The invention relates to the technical field of ultrasonic stress measurement, and discloses an ultrasonic axial force high-speed real-time measurement system which comprises a core processor module which controls a transducer to alternately transmit and receive longitudinal wave and transverse wave echo signals and calls a fingerprint template established based on a geometric structure of a bolt to perform cross-correlation operation so as to determine transit time, according to the method, by constructing the acoustic characteristic normalization ratio, the influence of uniform temperature change is inhibited on the aspect of the measurement principle, and the inherent problems of model misalignment and error amplification in a traditional compensation mode are avoided; echo positioning is carried out by using geometric fingerprints of the bolt, a filtering algorithm with high calculation amount is replaced, the reliability of the system is improved, and high-precision measurement can be realized on a low-power-consumption general processor.

The embodiment of the invention relates to the technical field of laser radars, in particular to a ranging parameter calibration method, a laser radar and a storage medium. According to the embodiment of the invention, the corresponding target compensation function and the target temperature change threshold value are obtained according to the target power-on temperature of the laser radar, and when the candidate temperature difference value corresponding to the point cloud in the target time period in the actual distance measurement process is greater than or equal to the target temperature change threshold value, the target compensation function and the target temperature change threshold value are compensated. And calibrating the actual flight time value corresponding to each frame of point cloud according to the target compensation function and the frame number of the point cloud, thereby obtaining the target flight time value corresponding to each frame of point cloud, improving the adaptability of the temperature change and the flight time change of the laser radar in the fluctuation time, improving the accuracy of the flight time value, and thus, improving the accuracy of the laser radar. The accurate distance measurement value can be calculated according to the flight time value, and the distance measurement accuracy is improved.

A distance measurement device includes a light emitter for transmitting pulsed light and a light receiver for detecting reflected light from an object, providing an output signal. The device has at least one of a circuit or a processor with memory storing executable computer program code. The circuit or processor calculates an object distance using the time of flight of the pulsed light. Additionally, a histogram representing received light intensity for each time of flight is generated from the output signal. The device determines whether the object is within a short-distance range based on the timing of a peak in the histogram, and calculates the object distance using both a feature value related to the number of light reflections and the timing of the peak's decline.

The present invention comprises: a plurality of light-emitting elements; a plurality of light receiving elements; and a determination means for determining, as a time of flight of the signal light for distance measurement, a time from emission of light from any of the plurality of light-emitting elements to reception of reflected light of the emitted signal light from any of the plurality of light-receiving elements. Among the plurality of light-receiving elements, a first light-receiving element receives reflected light and ambient light, the reflected light being signal light that has been emitted by a first light-emitting element among the plurality of light-emitting elements and has been reflected by the subject, each of the plurality of light-receiving elements including a plurality of sub-light-receiving elements, and a determination section obtaining a reference value from a measurement result of the time of flight measured using the detection signal of a first sub-light-receiving element, the first sub-light-receiving element being a portion of the first light-receiving element, the reference value indicating a measurement result of the ambient light that has been measured for each light-receiving element, and determining a time of flight of signal light for ranging in relation to the subject by using both: a reference value; and a measurement result of the time of flight measured using a detection signal of a second sub-light-receiving element that is included in the first light-receiving element and is different from the first sub-light-receiving element.

A method and system for providing distance information from a sensor assembly to a flying target. The method comprises detecting the flying target and locking on the flying target by means of a tracking sensor. Directing a light beam at the detected flying target. Generating a movement pattern having a path around the detected flying target and controlling movements of the light beam so that the LOS of the light beam completes moving across the path of the selected movement pattern within a set timeframe. Generating distance information by measuring time- of-flight of the light beam, when being reflected from the flying target while moving the LOS of the light beam across the path of the movement pattern. The system comprises sensors and devices for performing the method.

A distance measuring device (100) is provided with: a light emitting unit (40) that emits pulsed light; a light receiving unit (60) that receives reflected light of the pulsed light based on an object and outputs an output signal (Sout); and a calculation unit (210) that calculates the distance of the object using the time of flight of the pulsed light. The calculation unit is provided with: a histogram generation unit (230) for generating, on the basis of the output signal, a histogram (HG) indicating the received light intensity of the reflected light for each time of flight; a short-distance determination unit (240) that determines whether or not the object is in the distance range on the basis of the rising timing (RT) of the peak (PK) in the histogram; a feature quantity acquisition unit (250) that acquires a feature quantity relating to the number of reflections on the basis of the histogram; and a distance calculation unit (260, 260b) that, when the object is in the close range, calculates the object distance on the basis of the feature amount and the falling timing (FT) of the peak value.

The invention relates to the technical field of laser ranging, and discloses a three-way laser ranging method and system, and the method comprises the steps: obtaining a laser echo signal; transmitting the laser echo signal to an image sensor to obtain a three-way light spot image; performing morphological feature recognition on the three-way light spot image, judging whether the light spot of the three-way light spot image has abnormal deformation or not, obtaining a light spot recognition result, and obtaining a stability index of the light spot form in each direction based on the light spot recognition result; carrying out validity marking on the distance measurement data in each direction according to the light spot identification result to obtain effective direction distance measurement data, and generating an integrity index of the distance measurement data; and carrying out flight time calculation based on the effective direction distance measurement data to obtain three-dimensional coordinates of the target object. The method has the effect of improving the laser measurement reliability and the function of detecting the deformation of the to-be-measured object.

The application belongs to the technical field of space plasma environment detection, and particularly relates to a device and method for measuring particle composition and incident direction, which comprises: a detection unit array, which is respectively provided with a plurality of independent charge input channels in an inner circumferential direction and an outer circumferential direction; each charge output channel is used for outputting different initial charge pulse signals in the inner circumferential direction and different terminal charge pulse signals in the outer circumferential direction after a space charged particle is incident at an incident angle, and delay and amplification are performed respectively; and a back-end circuit analysis processing module, which is used for obtaining actual time of flight and actual incident azimuth angle time of the charged particle according to different initial pulse signals and terminal pulse signals collected for each charge output channel, obtaining the composition of the charged particle according to the obtained actual time of flight of the charged particle, and obtaining the actual incident azimuth angle of the charged particle according to the actual incident azimuth angle time.

The application provides a composite sandwich structure material damage identification method based on a Bayesian fusion algorithm, and the method comprises the following steps: extracting the time of flight of a scattered wave signal based on continuous wavelet transform; wherein the time of flight refers to the time for which the scattered wave signal generated by an excitation sensor is transmitted to a receiving sensor; obtaining a likelihood function based on the time of flight and an elliptical positioning method; determining a correlation coefficient based on a damage signal and a reference signal; in a RAPID method, taking the correlation coefficient as a damage sensitivity characteristic to determine a prior probability density function of a damage position; performing Bayesian estimation based on the likelihood function and the prior probability density function to obtain a posterior probability density function of the damage position; and fitting a damage positioning image using a Markov Monte Carlo method (MCMC) based on the posterior probability density function of the damage position.

This application relates to the field of lidar, and discloses a lidar ranging method, device, lidar, and storage medium. The method includes: acquiring a spot pattern on a lidar detector and plotting a time-of-flight histogram; determining the distance type between the object to be measured and the lidar based on the spot pattern; determining the target time-of-flight region in the time-of-flight histogram based on the distance type; determining the target time-of-flight based on the target time-of-flight region; and determining the ranging result based on the target time-of-flight. This application does not require peak location for all regions of the time-of-flight histogram, effectively reducing the amount of peak calculation, improving the efficiency of peak position calculation and fitting accuracy, and eliminating the need to store excessive noise peak data.

An angular sensitive time-of-flight position sensor device is provided and includes an array of pixels each comprising: a planar waveguide structure; a collection area with a grating pattern at a specific periodicity to couple incident light into the planar waveguide structure; at least one detector placed outside of the collection area and in a plane different from that of the planar waveguide structure; an output coupler to direct the light from planar waveguide to the at least one detector; a mask to shield the at least one detector from direct illumination; a narrow band light source that illuminates a field-of-view; a first electronics configured to detect the time-of-flight of light retroreflected, scattered, or both incident onto the position sensor and configured to provide distance ranging information; and a second electronics configured to interpret and retain time-of-flight information and configured to communicate with external electronics for system applications.

A sensor for time of flight calculation, including a laser configured to emit a plurality of pulses of light at a target, one or more SPADs configured to detect a TDC trigger event, where the first TDC trigger event includes one or more photons detected as an initial pulse of light of the plurality of pulses of light is reflected to the one or more SPADs, a counter configured to count the one or more photons of the first TDC trigger event and generate a first histogram of the one or more photons at a first resolution, a global window processor configured to read the first histogram and detect a peak of the first histogram, and a global histogram processor configured to detect a peak of the second histogram, wherein the peak of the second histogram determines a distance between the sensor and the target.

A time-of-flight (ToF) mass analyser is operated in a first mode of operation and a second mode of operation to obtain a first set of data and a second set of data respectively. The ion path has a dif

A multiple-pulses-in-air (MPiA) laser scanning system configured for measuring the time-of-flight of laser pulses, wherein the computing unit is configured for triggering the transmitter to transmit the send pulses with a varying pulse frequency, wherein the transmitter is configured to have a dead mode, wherein in the dead mode an increase in pulse frequency is effected, wherein in the course of increasing the pulse frequency, a reduction in pulse energy per individual send pulse of the send pulses is provided such that the pulse energy of the resulting return pulses is reduced such that it is below a detection threshold, and a measurement mode, wherein in the measurement mode a reduction in pulse frequency compared to the dead mode is effected.

The invention provides a DTOF ranging method and device capable of saving storage space and electronic equipment, and the method comprises the steps: decomposing an original laser period into two coprime positive integers, and obtaining a first exposure period and a second exposure period; exposing the target object in the first exposure period to obtain a first histogram; exposing the target object in a second exposure period to obtain a second histogram; performing peak searching processing on the first histogram and the second histogram to obtain first flight time corresponding to the highest peak in the first histogram and second flight time corresponding to the highest peak in the second histogram; and calculating distance information of the target object according to a linear relationship among the first exposure period, the second exposure period, the first flight time and the second flight time. The distance of the target object is obtained by decomposing the original laser period into the two co-prime exposure periods and then performing exposure twice, the maximum laser period is reduced while distance measurement is not affected, and thus the storage space of histogram statistics is effectively saved.

The invention provides a surface crack laser ultrasonic quantitative detection method, device, equipment and medium, and relates to the technical field of nondestructive detection.The method comprises the steps that laser ultrasonic B-scanning data are obtained through synchronous scanning, a multi-modal characteristic wave propagation mechanism is analyzed, a flight time analysis model is established, and the flight time analysis model is analyzed; and a theoretical and experimental multi-modal characteristic mode is constructed, and discretization similarity matching is carried out, so that the depth and the inclination angle of the surface crack are stably inverted in a full-parameter space, and quantitative detection is realized. According to the method, instability caused by dependence of a single mode or a single characteristic can be avoided, synchronous and high-precision quantitative detection on the surface crack depth and the crack inclination angle under the condition of complex multi-mode wave aliasing is realized, and the problems of insufficient characterization accuracy and robustness of geometric parameters of cracks in the prior art are solved.

The application relates to the field of nondestructive testing of aerospace composites, and provides a composite material detection method based on ultrasonic Lamb wave filtering back-projection imaging, which comprises the following steps: acquiring a Lamb wave signal passing through a composite material; denoising the Lamb wave signal to obtain an optimized Lamb wave signal; continuously wavelet transforming the optimized Lamb wave signal to acquire a time-of-flight parameter of the optimized Lamb wave signal in the composite material; and based on the time-of-flight parameter, combining a filtering back-projection method reconstruction algorithm to acquire an internal image of the composite material, so as to detect internal defects of the composite material. The application utilizes the Lamb wave signal, the continuous wavelet transform and the filtering back-projection method to acquire a high-quality composite material internal damage image with few artifacts without the assistance of a baseline signal, and can effectively, quickly and accurately perform nondestructive testing on a plate-shaped composite material.

The invention discloses an atomic substance wave length measuring device, which comprises a vacuum cavity, a first split beam and a second split beam which are obtained by light splitting of test laser penetrate through the vacuum cavity in a direction parallel to the height of the vacuum cavity and are detected by a first photoelectric detector after being combined, detection laser is further irradiated in the vacuum cavity, and the first photoelectric detector is connected with a second photoelectric detector through a second photoelectric detector. The test laser is split, the first split light and the second split light are combined to obtain combined light, and the shape defined by a middle light path is a rectangle. The invention also discloses an atomic substance wave wavelength measuring method, which comprises the following steps of: adjusting test laser into slit light, and actually measuring the flight time of a measured object; and adjusting the test laser to be continuous laser, and testing the actually measured flight distance of the measured object, thereby obtaining the actually measured flight speed and the wavelength of the substance wave of the measured object. The method is not influenced by the change of the initial position of the measured object, so that the flying speed measurement of the measured object can be improved, and the method is used for accurately measuring the wavelength of the substance wave.

In some embodiments, a measurement system may include a time to digital converter (TDC) configured to determine a first digitized time at which it receives a command signal and a second digitized time at which it receives an alert signal. The first digitized time and the second digitized time may be determined for N number of iterations. The command signal may be delayed by a delay time, and the delay time may be varied for each of the N number of iterations. The measurement system may include a first dynamic photodiode (DPD) configured to switch from a reverse bias mode to an active mode based on the command signal. The TDC may calculate a difference between the first digitized time and the second digitized time for each of the N number of iterations, and the difference may vary as the delay time is varied.

The application discloses a detonation test method and device based on laser technology in the technical field of detonation experiment test, S1, detonation ignition, makes the flyer pass through the first observation point, the second observation point and the third observation point in turn; S2, laser Doppler effect monitoring, wavelength change data when the laser beam irradiates the flyer is acquired through the end laser interferometer; then the first observation point, the second observation point and the third observation point respectively emit positioning laser beams to carry out again Doppler effect monitoring on the passing flyer, positioning wavelength change data is obtained; S3, the time when the flyer passes through each observation point is determined, the corresponding flying time and passing time of the flyer under the first observation point, the second observation point and the third observation point are obtained based on the wavelength change data and the positioning wavelength change data; then the passing time is corrected based on the flying time; so as to eliminate the cumulative error, make the obtained experimental data more accurate, and facilitate the accurate prediction of the speed of the flyer.

The application relates to a SPAD histogram distance calculation method and system based on coarse-precision two-stage mixed processing. The method comprises the following steps: performing full-width fast target detection on a photon time-of-flight histogram generated based on SPAD and TCSPC technology through first-stage processing to obtain coarse distance information corresponding to a target; dynamically judging whether to start second-stage processing on the target according to signal characteristics corresponding to the coarse distance information; if it is judged to start second-stage processing, performing high-precision peak position positioning on the target time window corresponding to the coarse distance information through second-stage processing to obtain accurate time-of-flight information of the target; if it is judged not to start second-stage processing, directly taking the time-of-flight corresponding to the coarse distance information as the final time-of-flight information of the target; and converting the final time-of-flight information of the target into an accurate measurement distance through a preset mapping relationship between the speed of light and the distance to simultaneously meet real-time requirements and power consumption control.

This application relates to the field of laser ranging and velocimetry technology, providing a laser ranging and velocimetry method, device, system, and storage medium. It involves emitting a linearly swept-frequency optical signal towards a target object during the i-th sweep time of each measurement cycle; emitting a pulsed optical signal towards the target object during the i-th pulse time of each measurement cycle; obtaining the distance of the target object during the i-th pulse time of each measurement cycle based on the flight time of the pulsed optical signal emitted during the i-th pulse time of each measurement cycle; and obtaining the velocity of the target object during the i-th sweep time of each measurement cycle based on the flight time of the pulsed optical signal emitted during the i-th pulse time of each measurement cycle and the beat frequency of the beat frequency signal corresponding to the linearly swept-frequency optical signal emitted during the i-th sweep time. This method enables rapid detection of the distance and velocity of the target object and achieves decoupling of the distance and velocity of nearby targets.

A technique for determining the smearing of the kinetic energy of a hadron beam, using elements of the particle time of flight method, where all amplitudes for the measured signals SA(k) and SB(k) are recorded simultaneously from two detectors (A) and (B) located at a precisely defined distance L from each other and connected to the processing unit enabling the analysis of images recorded by both detectors, placed along the line of the studied hadron beam, over a period of time corresponding at least to 100 times the theoretical value for the time of flight of a hadron beam particle between the detectors (A) and (B), with time resolution at least on the level of 0.5 ns. Signals, for which the amplitude value is lower than the defined noise level and signals, the profile of which deviates from the determined reference profile, are eliminated.

Embodiments relate to an apparatus, method, or computer program. A laser may be configured to irradiate a plurality of laser pulses on a target area to ionize a sample placed in the target area into at least one ionized particle. Electrodes at a first end of a flight tube may be configured to accelerate ionized particles into the flight tube. A detector at a second opposite end of the flight tube may independently measure a time of flight of the ionized particles through the flight tube and an intensity of the ionized particles.

Aspects of the subject disclosure may include, for example, a light detection and ranging system (100) that includes a laser light source, scanning mirrors, light-sensitive devices, and time-of-flight measurement circuits (150). The angular velocity of the scanning mirrors is adjusted in a region of interest to modify resolution. A scanning mirror on a fast scan axis slows down entering the region and speeds up exiting, while a scanning mirror on a slow scan axis does the opposite. The system may also increase a laser pulse repetition rate in the region of interest for enhanced data acquisition. Other embodiments are disclosed.

The invention discloses a time spectrometer system and method based on a microchannel plate photomultiplier (MCP-PMT). The constant proportion discriminator is triggered by adopting an attenuation branch / delay branch differential zero crossing point, and performs latch width limiting and level conversion on a trigger pulse; fPGA-based multi-level carry chain time TDC is adopted, and parallel tap sampling, bubble suppression and code density calibration table look-up correction are carried out; a processing flow of time window histogram accumulation, a first effective hit strategy, a background adaptive threshold and multi-peak positioning and fitting is adopted. According to the invention, the picosecond-level timing precision is obtained at a low clock rate, the sensitivity and precision of weak light signal flight time distance measurement are significantly improved, and the method is suitable for laser radar imaging and high time sequence of time correlation single photon counting, can realize sub-hundred picosecond-level time resolution, and is suitable for flight time distance measurement under a weak light condition.

The present application relates to the technical field of liquid level measurement, and particularly relates to a liquid level accurate measurement method and system based on a magnetostrictive liquid level meter, comprising: synchronously collecting liquid level data of the magnetostrictive liquid level meter and attitude data of a tank body; calculating a liquid measurement characteristic evaluation value according to the liquid level data and the attitude data; calculating a dynamic specificity index according to a change trend of the liquid measurement characteristic evaluation value over time and historical statistical characteristics thereof; calculating a magnetic force compensation ratio according to the dynamic specificity index and a historical maximum value of the liquid measurement characteristic evaluation value; adjusting an excitation driving current of the magnetostrictive liquid level meter according to the magnetic force compensation ratio, detecting a return wave and measuring a time of flight, and outputting a final liquid level value after conversion. The present application can actively and differentially compensate for magnetic force according to different liquid sensitivities and dynamic change degrees, thereby significantly improving liquid level measurement accuracy and system robustness under dynamic working conditions.

An imaging system (1) has: a light transmission system (5, 8) configured to generate and steer an output light signal (LO); a light receiving system (6, 12) configured to detect an input light signal (LI); and electronic resources (3, 4, 5, 16, 17, 18) configured to control the light transmission system and the light receiving system and to perform imaging based on a time-of-flight between emission of the output light signal and detection of the input light signal. The imaging system is configured to perform an imaging calibration (51) comprising: acquiring an environment map (ENV_MAP) that represents a three- dimensional image of an area scanned by the output light signal; and identifying, from the environment map, the presence of one or more objects (60, 61, 62) in the scanned area. The imaging system is further configured to: perform (53) a Line-of-Sight, LOS, imaging of a region of interest within the scanned area; and perform (54) a Non-Line-of- Sight, NLOS, imaging by illuminating, as a relay surface, at least one of the objects (61) identified within the scanned area.

A method of ranging using a time-of-flight (ToF) ranging system includes: receiving, by a processor, a histogram generated by a ToF imager of the ToF ranging system, where the ToF imager is configured to transmit a light pulse for ranging purpose; finding a rising edge of a pulse region in the histogram, where the pulse region corresponds to a reflected light pulse from a target; fine-tuning a location of the rising edge by performing a fitting process between the rising edge and a pre-stored high-solution rising edge; and calculating an estimate of a distance of the target by adding a pre-determined offset to a distance of the rising edge after fine-tuning the location of the rising edge.

To minimize the increase in measurement time while ensuring detection performance for distant objects. [Solution] In this distance measuring device, the unit frame for distance measurement is divided into multiple subframes, and the groups of measurement directions assigned to each of the multiple subframes are set to be mutually exclusive. When multiple reflection points are detected in a first subframe which is relatively earlier than the multiple subframes, the controller sets a first region including each of the reflection points based on the time of flight of light at each of the reflection points or a converted value equivalent to the time of flight of light. In a second subframe which is at least one of the multiple subframes which is relatively later than the first subframe, the controller controls the operation of the light source and the deflector so that measurement light is not irradiated from the group of measurement directions included in the second subframe in one or more measurement directions that overlap with the first region, and measurement light is irradiated in measurement directions that do not overlap with the first region.