CN114061902A - Real-time monitoring device, method and system for egg and gravel transportation based on image method - Google Patents
Real-time monitoring device, method and system for egg and gravel transportation based on image method Download PDFInfo
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Abstract
The invention discloses a real-time monitoring device, a real-time monitoring method and a real-time monitoring system for gravel transportation based on an image method. The upper cover plate and the lower cover plate mutually enclose to form an accommodating cavity. Adapter, pressure sensor, attitude sensor and camera all set up hold the intracavity, be equipped with transparent window on the upper cover plate. The monitoring method adopts the cooperation of an acoustic method, a pressure method and a camera shooting method, wherein the acoustic method and the pressure method can independently calculate the transportation amount, the calculation results of the two methods can be mutually verified, and meanwhile, the particle size calculated and analyzed by the camera shooting method is used for detecting the accuracy of the acoustic method, so that the accuracy of the transportation of pebbles can be improved.
Description
Technical Field
The invention relates to the technical field of channel monitoring, in particular to a real-time monitoring device, a real-time monitoring method and a real-time monitoring system for gravel transportation based on an image method.
Background
Since the formal water storage operation of the three gorges project, the channel condition of the three gorges reservoir area is greatly improved, but the problem of navigation obstruction in the collapse period caused by the transportation of gravel in the reservoir change water return area is very serious, so the observation technology of the gravel bed load prototype is very important. The existing gravel bed load monitoring method mainly comprises a direct method and an indirect method: the pit measurement method in the direct method has high operation difficulty and high cost, and cannot carry out fine observation; sampler methods also do not allow high resolution monitoring of the bed load. Indirect methods are classified into tracing methods, imaging methods, acoustic methods, and the like. Because the bed load moves randomly in time and space, accurate information cannot be captured by using a sampler for sampling, the sampler interferes with the water flow conditions around equipment in the sampling process, bed load particles moving at high speed impact the sampler to cause certain damage, and shipboard operation is not suitable for the high-speed water flow condition; the pit measurement method can only estimate the gravel transportation amount after the flood, and cannot acquire the dynamic change of the bed load mass along with the time; the tracing method, whether adopting radioactive particles, radio tracking technology or magnetic tracing particles, has limited research particle size range, and the particles are buried in each other in the moving process, the recovery rate is low, some particles can cause certain pollution to the environment, the manufacturing cost is high, and the testing cost is high; the optical measurement method is mainly used for observing the movement of the underwater bed load through a high-definition camera, has higher requirements on the water quality and the sand content of an observation environment, and has the advantages that necessary protection must be carried out on an instrument, and meanwhile, effective lighting measures are provided; the ultrasonic topography instrument is greatly influenced by resolution, timeliness, water flow conditions and sand content, and observation results are difficult to meet requirements.
The existing monitoring device and method for monitoring the transportation of pebbles have low accuracy, so that a pebble transportation monitoring device and method with higher accuracy are continuously provided.
Disclosure of Invention
In view of the above disadvantages, the present invention provides a real-time monitoring device, method and system for pebble migration based on an image method, which solves the problem of inaccurate pebble migration monitoring in the prior art by using a monitoring method of pressure coupling and audio-video coupling.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
the utility model provides an ovum gravel is transported and is moved real-time supervision device based on image method, includes upper cover plate, lower apron, adapter, pressure sensor, attitude sensor and camera. The upper cover plate and the lower cover plate mutually enclose to form an accommodating cavity. Adapter, pressure sensor, attitude sensor and camera all set up hold the intracavity, be equipped with transparent window on the upper cover plate for the camera is shot.
By adopting the structural design, the multiple monitoring method for pebble transportation can be realized through the sound pick-up, the pressure sensor and the camera, mutual verification can be realized, and the accuracy of pebble transportation monitoring is improved.
Further, upper cover plate and lower apron adopt the metal sheet, the adapter is fixed to be installed on the upper cover plate, wherein the upper cover plate as the syntonizer with the adapter cooperation is used, pressure sensor is a plurality of, and pressure sensor sets up the apex angle department that holds the chamber, and is located play the supporting role between upper cover plate and the lower apron, pressure sensor upper end with upper cover plate rigid connection, pressure sensor's lower extreme is equipped with the mount pad, the mount pad with the contact of apron down.
Further, the camera is fixedly installed on the lower cover plate and located under the window, and the camera adopts a super wide-angle camera.
Further, enclose to close through the safety cover between upper cover plate and the lower cover plate and form hold the chamber, adapter, pressure sensor, attitude sensor and camera all pass through the external data storage ware of electric wire electric connection.
Furthermore, a through hole is formed in the protective cover and used for installing the electric wire, and the through hole, the protective cover and the joint of the upper cover plate and the lower cover plate are sealed.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
a real-time monitoring method for the transportation of pebbles based on image method includes such steps as providing a real-time monitor,
a. installation: arranging a monitoring device in a river channel of an observation point, horizontally fixing the monitoring device, and connecting the monitoring device with an onshore electric box or a computer terminal through a cable;
b. data acquisition: collecting audio information of the transportation of the river bottom gravel and eggs through a pickup, collecting pressure information borne by an upper cover plate in the transportation process of the gravel and eggs through a pressure sensor, collecting horizontal state information of a monitoring device through an attitude sensor, and collecting picture information of the gravel and eggs passing through the upper cover plate in a shooting area through a camera to obtain a gravel image;
c. and (3) data analysis: calculating and analyzing the audio information collected by the pickup by an acoustic method to obtain the particle size and the transportation amount of pebbles; meanwhile, analyzing and calculating the weight information of the pebbles collected by the pressure sensor by a pressure method to obtain the corresponding pebble conveying and transferring amount; analyzing and reconstructing the particle size of pebbles according to the information of pebble pictures acquired by a camera shooting method;
d. data verification: and comparing and verifying the pebble transportation amount calculated by an acoustic method and a pressure method, and comparing and verifying the particle size calculated by the camera shooting method and the particle size calculated by the acoustic method, so that the accuracy of monitoring the pebble transportation amount is ensured by adopting a double verification method.
Further, the acoustic method in step c is as follows:
1) the audio acquisition sets up the pickup area of adapter, inserts the audio signal of gathering into computer sound card, utilizes the audio frequency to record and store, designs audio sampling frequency for the record of every second, improves the fidelity of audio frequency, sets up sampling frequency according to audio signal's frequency, sets up according to the sampling theorem, and the sampling theorem is: let the sampling frequency be fsThe maximum frequency of the target signal is fmaxWhen f iss≥2fmaxDuring the process, the collected audio frequency can completely embody the characteristics of the audio signal, so that the fidelity of the audio signal is realized, according to a preliminary test, the frequency of pebble collision on the audio signal is not more than 6000Hz, so that the sampling frequency is set to be 16KHz, the storage space is saved on the premise of ensuring the fidelity of the audio signal, the subsequent processing efficiency is improved, the audio sampling precision determines the dynamic range of sound, the precision of the audio time domain waveform amplitude is reflected, all aspects are considered comprehensively, the sampling precision is finally set to be 16 bits, namely, the value range of a single sampling point is 216A stage;
2) analyzing the characteristics of the pebble movement signal, wherein the original audio acquired by the test can be subjected to characteristic identification only by preprocessing, and the method mainly comprises the steps of framing and windowing, noise reduction and end point detection;
3) the method comprises the following steps of identifying the particle size of pebbles, wherein the characteristics of audio signals generated by the pebbles with different particle sizes are different, wherein the characteristics comprise amplitude characteristics, generally speaking, the pebbles with larger particle sizes have larger amplitude, the generated audio signals have larger energy, the particle size of the pebbles can be judged according to the audio amplitude generated by the pebble collision in the audio signals, and the method comprises the following steps: firstly, extracting a maximum amplitude from each section of audio signal detected by an end point as a characteristic amplitude of a current collision pebble, calculating an average value of all amplitudes, determining a relation between the amplitude of the pebble and the particle size of the pebble, fitting the relation through a test result, obtaining a fitting equation and calculating the particle size;
4) calculating the transport and transportation amount of pebble bed load, wherein the calculation formula of the transport and transportation amount M of pebble bed load is as follows:
wherein n is the number of pebbles passing through the upper panel of the instrument, m is the mass of a single pebble, rho is the density of the pebbles, and D is the isovolumetric particle size of the pebbles. By using the formula, the pebble bed load transfer amount passing through the upper panel of the instrument per hour can be calculated according to the audio signals collected by the instrument.
Further, the pressure method in step c is as follows:
the pressure method for calculating the pebble transport volume is to further convert the measured pressure data to obtain the pebble bed transport volume in a certain time period, and the methods for calculating the pebble transport volume comprise two methods: firstly, under the condition of short transportation time, the measured pressure data is the pebble stacking weight m in a period of time; secondly, under the condition of long-time transportation, the total transportation amount of pebbles is calculated through further data processing, and the specific calculation steps are mainly divided into four steps: firstly, setting the current return data and the next data of the instrument as X respectively1And X2；②X1And X2The difference value is the weight of the transported gravel in a single data return period; thirdly, calculating the weight m of the gravel in each data return period in the total transportation timei(ii) a Fourthly, the weight of the pebbles in each data return periodQuantity miThe sum is the total mass m of the gravel in the total transportation time.
Further, according to the principle of the image pickup method in the step c, when pebbles pass through the image pickup area of the camera, the camera can directionally observe the pebbles passing through the upper panel to obtain a plurality of pebble images, after the original observation image is obtained, the images photographed by the camera need to be spliced and fused, the photographed video is divided into one frame and one frame of images, the inter-frame difference is carried out on the images, the shape of the pebbles passing through the upper panel is restored through matlab codes, and then the size and the particle size information are obtained.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
an image method-based real-time monitoring system for egg gravel transportation comprises: monitoring devices with monitoring devices through cable electric connection set up in with shore electric box or computer terminal.
The invention has the beneficial effects that:
according to the real-time monitoring device, method and system for pebble transport based on the image method, through the matching of the sound pick-up, the pressure sensor and the camera, when equipment with small pebble transport volume is not buried, audio is collected through the sound pick-up and the main effect of the acoustic method is adopted for measurement, when the equipment is buried by pebbles, the pressure sensor collects pressure signals and the main effect of pressure method observation is adopted, meanwhile, the shooting assistance of the camera is matched, particle size comparison and verification are analyzed, and the monitoring accuracy of the acoustic method and the pressure method is detected.
The invention is further described with reference to the following figures and examples.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:
FIG. 1 is an exploded view of a real-time monitoring device for the transportation of pebbles based on an image method;
FIG. 2 is a side view of the real-time monitoring device for the transportation of gravel based on an image method;
FIG. 3 is a schematic diagram of an interframe difference method of the real-time monitoring method for the gravel transportation based on the image method.
The reference numerals in the drawings are explained below.
Detailed Description
In order to explain technical contents, structural features, and objects and effects of the present invention in detail, the following detailed description is given with reference to the accompanying drawings in conjunction with the embodiments.
The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.
Referring to fig. 1 and 2, a real-time monitoring device for gravel transportation based on an image method includes an upper cover plate 1, a lower cover plate 2, a sound pickup 3, a pressure sensor 4, an attitude sensor 5, and a camera 6. Upper cover plate 1 and lower apron 2 enclose each other and close to form and hold chamber 1a, adapter 3, pressure sensor 4, attitude sensor 5 and camera 6 all set up hold in the chamber 1a, be equipped with transparent window 1b on the upper cover plate 1 for camera 6 shoots. The upper cover plate 1 and the lower cover plate 2 are made of metal plates, the sound pickup 3 is fixedly arranged on the upper cover plate 1, and the upper cover plate 1 is used as a resonator and matched with the sound pickup 3. Pressure sensor 4 is a plurality of, and pressure sensor 4 sets up the apex angle department that holds chamber 1a, and is located play the supporting role between upper cover plate 1 and the lower cover plate 2. The upper end of the pressure sensor 4 is rigidly connected with the upper cover plate 1, the lower end of the pressure sensor 4 is provided with a mounting seat 4a, the mounting seat 4a is in contact with the lower cover plate 2 and is not fixed, so that the pressure sensor 4 has a certain deformation space, and the mounting seat 4a supports the whole upper cover plate 1. In this embodiment, the pressure sensors 4 are designed to be 4, and are respectively disposed at 4 top corners of the upper cover plate 1 a. In the present invention, the pressure sensor 4 can convert the minute deformation of the mount 4a caused by the pressure into an electric signal, and perform data transmission using the high-speed module H5. The high-speed module has the functions of changing module addresses, setting AD speed, reading weight and the like. The module communication mode adopts RS485, and the communication baud rate is 115200 bps. The module can interact with the computer by using serial port communication software, and can convert the module response information into a pressure value to return to the computer by using a specific transcoding protocol. The four pressure sensors 4 are all independently provided with data transmission modules, each pressure sensor can independently work, and the corresponding data transmission modules can independently receive instructions and return data.
The camera 6 is fixedly arranged on the lower cover plate 2 and is positioned under the window 1b, and the camera 6 adopts a super wide-angle camera. Enclose through safety cover 7 between upper cover plate 1 and the lower cover plate 2 and close and form hold chamber 1a, adapter 3, pressure sensor 4, attitude sensor 5 and camera 6 all pass through the external data storage ware of electric wire electric connection. In this embodiment, a through hole is formed in the protective cover 7 for installing an electric wire, and the connection between the through hole and the protective cover 7 and the upper cover plate 1 and the lower cover plate 2 is sealed.
A real-time monitoring method for the transportation of pebbles based on image method includes such steps as providing a real-time monitor,
a. installation: arranging a monitoring device in a river channel of an observation point, horizontally fixing the monitoring device, and connecting the monitoring device with an onshore electric box or a computer terminal through a cable;
b. data acquisition: collecting audio information of the transportation of the river bottom gravel and eggs through a pickup 3, collecting pressure information borne by an upper cover plate 1 in the transportation process of the gravel and eggs through a pressure sensor 4, collecting horizontal state information of a monitoring device through an attitude sensor 5, and collecting picture information of the gravel and the eggs passing through the upper cover plate 1 in a shooting area through a camera 6 to obtain a gravel image;
c. and (3) data analysis: calculating and analyzing the audio information collected by the pickup 3 by an acoustic method to obtain the pebble particle size and the pebble transport amount; meanwhile, the pebble weight information collected by the pressure sensor 4 is analyzed and calculated by a pressure method to obtain the corresponding pebble conveying and transferring amount; analyzing and reconstructing the particle size of pebbles according to the pebble photo information acquired by the camera 6 by a camera shooting method;
d. data verification: and comparing and verifying the pebble transportation amount calculated by an acoustic method and a pressure method, and comparing and verifying the particle size calculated by the camera shooting method and the particle size calculated by the acoustic method, so that the accuracy of monitoring the pebble transportation amount is ensured by adopting a double verification method.
The acoustic method in the step c is as follows:
1) and audio acquisition, namely, the pickup area of the pickup 3 is set, the moving pebbles pass through the upper panel of the instrument and impact the upper panel to generate sound, and the pickup can record the sound. The underwater sound environment is complex, irrelevant noise is often doped, valuable pebble sound is covered, the quality of audio recorded by the sound pick-up is poor, and subsequent analysis is difficult to perform, so that the sound pick-up area of the sound pick-up is set to be small, the sound of pebbles impacting an upper panel can be sensitively recorded, meanwhile, the influence of environmental noise is weakened, the quality of recorded audio signals is improved from the source, and the subsequent processing is facilitated. The audio signal with the collection inserts the computer sound card, utilizes the audio frequency to record and store, designs audio frequency sampling frequency for the record of every second, improves the fidelity of audio frequency, sets up sampling frequency according to audio signal's frequency, sets up according to the sampling theorem, and the sampling theorem is: let the sampling frequency be fsTarget signalMaximum frequency fmaxWhen f iss≥2fmaxDuring the process, the collected audio frequency can completely embody the characteristics of the audio signal, so that the fidelity of the audio signal is realized, according to a preliminary test, the frequency of pebble collision on the audio signal is not more than 6000Hz, so that the sampling frequency is set to be 16KHz, the storage space is saved on the premise of ensuring the fidelity of the audio signal, the subsequent processing efficiency is improved, the audio sampling precision determines the dynamic range of sound, the precision of the audio time domain waveform amplitude is reflected, all aspects are considered comprehensively, the sampling precision is finally set to be 16 bits, namely, the value range of a single sampling point is 216Stages (-32768 to 32768).
2) The method mainly comprises the steps of framing and windowing, noise reduction and end point detection.
a. Framing and windowing
The original audio signal of a pebble impact is an unsteady, time-varying signal. But the sound is formed by the excitation pulses of the glottis through the vocal tract, and the audio signal can be considered "quasi-stationary" in the "shorter time" range. It is generally considered that an audio signal has a "quasi-stationary" characteristic in a time range of 10ms to 30 ms. Based on the quasi-stationary characteristic of audio in small time scale, the speech signal can be analyzed by using short-time analysis technology.
In order to make audio analysis available for short periods, the audio signal is divided into segments, each of which is called a "frame", and the frame length is typically 10ms to 30 ms. Although each frame has a small time scale and can be processed as a steady-state signal, the number of frames is large, the variation of the feature parameter of each frame may be very large, and in order to make the feature parameter change smoothly between each frame, a certain overlap portion is usually allowed between adjacent frames.
Different signals have different requirements on the window function. A plurality of scrambling rates are distributed widely, and a window function with a fast side lobe attenuation speed is selected; if the interference frequency is close to the target frequency, a window function with a smaller side lobe peak value should be selected. Wherein the haining window has a better frequency resolution and a lower frequency leakage, so that the pebble impact audio signal preferably uses the haining window as a window function.
Noise reduction
When a laboratory actually records, it is very difficult to record a pure audio signal, and the surrounding environment is inevitably doped with noise, such as water flow sound, the sound of a water pump, and the like. The finally recorded audio signal is formed by mixing a pure moving pebble impact audio signal and noise together. The existence of noise destroys acoustic characteristic parameters of the moving pebble audio signal, so that the quality of the audio signal is reduced, and the difficulty of analyzing the audio signal is increased. In order to solve this problem, it is necessary to reduce the noise interference in the noisy audio, improve the signal-to-noise ratio of the audio signal as much as possible, reduce the distortion of the audio signal, and improve the audio quality.
The audio signal recorded in the test is a single-channel audio signal, and the involved noise (water flow, water pump and the like) can be regarded as additive noise with stable statistics, so that the noise can be reduced by using a 'spectral subtraction method' commonly used for reducing the influence of the additive noise.
c. Endpoint detection
The original audio can be regarded as a continuous time sequence, but the pebble collisions are usually not continuous in time scale, and the two collisions generally have a certain time interval, which is usually background noise, and can be regarded as an invalid segment. The processing of the silence segment is not considered in the audio signal feature analysis, so that the workload can be greatly reduced, and the efficiency of the audio signal acoustic feature analysis can be improved. The end point detection of the audio signal can distinguish an effective signal section from an ineffective section, so that a starting point and an ending point of the effective signal section in time can be obtained, and the method can be used for counting the pebble collision times.
If the signal-to-noise ratio of the original audio signal is extremely high or the signal-to-noise ratio of the audio signal after the noise reduction enhancement processing is extremely high, the beginning and end time points of the effective audio signal can be directly detected by using short-time energy. The algorithm has the characteristics of simplicity, high calculation efficiency and suitability for pebble audio signal endpoint detection with high signal-to-noise ratio.
3) The method comprises the following steps of identifying the particle size of pebbles, wherein the characteristics of audio signals generated by the pebbles with different particle sizes are different, wherein the characteristics comprise amplitude characteristics, generally speaking, the pebbles with larger particle sizes have larger amplitude, the generated audio signals have larger energy, the particle size of the pebbles can be judged according to the audio amplitude generated by the pebble collision in the audio signals, and the method comprises the following steps: firstly, extracting a maximum amplitude from each section of audio signal detected by an end point as a characteristic amplitude of a current collision pebble, calculating an average value of all amplitudes, determining a relation between the amplitude of the pebble and the particle size of the pebble, fitting the relation through a test result, obtaining a fitting equation and calculating the particle size;
4) calculating the transport and transportation amount of pebble bed load, wherein the calculation formula of the transport and transportation amount M of pebble bed load is as follows:
wherein n is the number of pebbles passing through the upper panel of the instrument, m is the mass of a single pebble, and rho is the density of the pebbles, and rho is 2.65 (g/cm)3) D is the equal volume grain size of pebbles. By using the formula, the pebble bed load transfer amount passing through the upper panel of the instrument per hour can be calculated according to the audio signals collected by the instrument.
Further, the pressure method in step c is as follows:
the pressure method pebble bed load transfer amount is calculated by further converting the measured pressure data to obtain the pebble bed load transfer amount in a certain time period. The pebble transport volume calculation methods include two methods: firstly, under the condition of short transportation time, the measured pressure data is the weight m of the pebble piled in a period of time. Secondly, under the condition of long-time transportation, the total transportation amount of pebbles is calculated through further data processing, and the specific calculation steps are mainly divided into four steps: firstly, setting the current return data and the next data of the instrument as X respectively1And X2；②X1And X2The difference value is the weight of the transported gravel in a single data return period; thirdly, calculating the weight m of the gravel in each data return period in the total transportation timei(ii) a Fourthly, the weight m of the pebbles in each data return periodiThe sum is the total of transportationTotal mass m of gravel eggs over time.
The pressure method can also measure the pebble stacking thickness, the pebble stacking thickness is calculated by utilizing data measured by the pressure method to calculate the thickness of pebbles stacked on a top plate, the calculation method assumes that the stacked pebbles cover the top plate of the whole instrument and the stacked pebbles are regarded as regular cuboids, and the used calculation formula is as follows:
Vstack＝mt/ρStack(1-1)
In the formulae (1-1) and (1-2), VStackIs a conglomeration of pebbles, mtActually measuring the mass of the piled pebbles in a non-submerged state, rhoStackThe gravel packing density is a fixed value, the packing density of natural gravel is adopted, h is the thickness of the gravel pack, and b is the width of the instrument.
For the calculation of the underwater pebble stacking thickness, the formula (1-1) can be further converted, and the formula (1-2) is combined to obtain a calculation formula of the pebble stacking thickness in the submerged state:
in the formula (1-3), VStackM is the volume of the pebbles transported and accumulatedt1Measuring the packed pebble mass, rho, for a flooded GPVSStackThe density of the gravel pile is rho is the water density, rhosIs the gravel-egg density.
Referring to fig. 3, the principle of the image pickup method in step c is that an interframe difference method is adopted, when pebbles pass through an area photographed by the camera 6, the camera 6 can directionally observe pebbles passing through the upper panel to obtain a plurality of pebble images, after an original observation image is obtained, the images photographed by the camera 6 need to be spliced and fused, a photographed video is divided into one frame and one frame of images, interframe difference is performed on the images, the form of the pebbles passing through the upper panel is restored through matlab codes, and then size and particle size information is obtained. The particle size of pebbles can be identified by a camera shooting method, and the particle size is verified with the particle size fitted by an acoustic method. The acoustic method and the pressure method can independently calculate the displacement, and the calculation results of the two methods can be verified mutually.
An image method-based real-time monitoring system for egg gravel transportation comprises: monitoring devices with monitoring devices through cable electric connection set up in with shore electric box or computer terminal.
Variations and modifications to the above-described embodiments may occur to those skilled in the art, which fall within the scope and spirit of the above description. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and variations of the present invention should fall within the scope of the claims of the present invention. In addition, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation, the use of the term being generic or similar to other means being encompassed by the invention.
Claims (10)
1. The utility model provides an ovum gravel is transported and is moved real-time supervision device based on image method which characterized in that: including upper cover plate (1), lower apron (2), adapter (3), pressure sensor (4), attitude sensor (5) and camera (6), upper cover plate (1) and lower apron (2) enclose each other and close to form and hold chamber (1a), adapter (3), pressure sensor (4), attitude sensor (5) and camera (6) all set up hold in chamber (1a), be equipped with transparent window (1b) on upper cover plate (1) for camera (6) are shot.
2. The image-based real-time monitoring device for egg gravel transportation according to claim 1, wherein: upper cover plate (1) and lower apron (2) adopt the metal sheet, adapter (3) are fixed to be installed on upper cover plate (1), wherein upper cover plate (1) as the syntonizer with adapter (3) cooperation is used, pressure sensor (4) are a plurality ofly, and pressure sensor (4) set up the apex angle department that holds chamber (1a), and are located play the supporting role between upper cover plate (1) and lower apron (2), pressure sensor (4) upper end with upper cover plate (1) rigid connection, the lower extreme of pressure sensor (4) is equipped with mount pad (4a), mount pad (4a) with apron (2) contact down.
3. The image-based real-time monitoring device for egg gravel transportation according to claim 1, wherein: the camera (6) is fixedly arranged on the lower cover plate (2) and is positioned under the window (1b), and the camera (6) adopts an ultra-wide-angle camera.
4. The image-based real-time monitoring device for egg gravel transportation according to claim 1, wherein: enclose to close through safety cover (7) between upper cover plate (1) and the lower cover plate (2) and form hold chamber (1a), adapter (3), pressure sensor (4), attitude sensor (5) and camera (6) all are through the external data storage ware of electric wire electric connection.
5. The image-based real-time monitoring device for egg stone transport as claimed in claim 4, wherein: the protective cover (7) is provided with a through hole for installing an electric wire, and the joints of the through hole, the protective cover (7), the upper cover plate (1) and the lower cover plate (2) are all sealed.
6. An image-based real-time monitoring method for egg gravel transportation, which adopts the monitoring device of any one of claims 1 to 5, and is characterized in that: comprises the following steps of (a) carrying out,
a. installation: arranging a monitoring device in a river channel of an observation point, horizontally fixing the monitoring device, and connecting the monitoring device with an onshore electric box or a computer terminal through a cable;
b. data acquisition: collecting audio information of the transportation of river bottom gravel by a pickup (3), collecting pressure information borne by an upper cover plate (1) in the transportation process of the gravel by a pressure sensor (4), collecting horizontal state information of a monitoring device by an attitude sensor (5), and collecting pebble photo information passing through the upper cover plate (1) in a shooting area by a camera (6) to obtain a pebble image;
c. and (3) data analysis: calculating and analyzing the audio information collected by the sound pickup (3) by an acoustic method to obtain the pebble particle size and the pebble transport amount; meanwhile, the corresponding pebble output and transfer amount is obtained by analyzing and calculating the pebble weight information collected by the pressure sensor (4) through a pressure method; analyzing and reconstructing the particle size of pebbles according to the information of pebble photos collected by a camera (6) by a camera method;
d. data verification: and comparing and verifying the pebble transportation amount calculated by an acoustic method and a pressure method, and comparing and verifying the particle size calculated by the camera shooting method and the particle size calculated by the acoustic method, so that the accuracy of monitoring the pebble transportation amount is ensured by adopting a double verification method.
7. The image-based method for monitoring the movement of pebbles in real time according to claim 6, wherein: the acoustic method in the step c is as follows:
1) the audio acquisition sets up the pickup area of adapter (3), inserts the audio signal of gathering into computer sound card, utilizes the audio frequency to record and store, designs audio frequency sampling frequency for the record of every second, improves the fidelity of audio frequency, sets up sampling frequency according to audio signal's frequency, sets up according to the sampling theorem, and the sampling theorem is: let the sampling frequency be fsThe maximum frequency of the target signal is fmaxWhen f iss≥2fmaxDuring the process, the collected audio frequency can completely embody the characteristics of the audio signal, so that the fidelity of the audio signal is realized, according to a preliminary test, the frequency of pebble collision on the audio signal is not more than 6000Hz, so that the sampling frequency is set to be 16KHz, the storage space is saved on the premise of ensuring the fidelity of the audio signal, the subsequent processing efficiency is improved, the audio sampling precision determines the dynamic range of sound, the precision of the audio time domain waveform amplitude is reflected, all aspects are considered comprehensively, the sampling precision is finally set to be 16 bits, namely, the value range of a single sampling point is 216Stage (-32768 to 32768);
2) analyzing the characteristics of the pebble movement signal, wherein the original audio acquired by the test can be subjected to characteristic identification only by preprocessing, and the method mainly comprises the steps of framing and windowing, noise reduction and end point detection;
3) the method comprises the following steps of identifying the particle size of pebbles, wherein the characteristics of audio signals generated by the pebbles with different particle sizes are different, wherein the characteristics comprise amplitude characteristics, generally speaking, the pebbles with larger particle sizes have larger amplitude, the generated audio signals have larger energy, the particle size of the pebbles can be judged according to the audio amplitude generated by the pebble collision in the audio signals, and the method comprises the following steps: firstly, extracting a maximum amplitude from each section of audio signal detected by an end point as a characteristic amplitude of a current collision pebble, calculating an average value of all amplitudes, determining a relation between the amplitude of the pebble and the particle size of the pebble, fitting the relation through a test result, obtaining a fitting equation and calculating the particle size;
4) calculating the transport and transportation amount of pebble bed load, wherein the calculation formula of the transport and transportation amount M of pebble bed load is as follows:
wherein n is the number of pebbles passing through the upper panel of the instrument, m is the mass of a single pebble, and rho is the density of the pebbles (taking rho as 2.65 (g/cm))3) D is the equal volume grain diameter of pebbles. By using the formula, the pebble bed load transfer amount passing through the upper panel of the instrument per hour can be calculated according to the audio signals collected by the instrument.
8. The image-based method for monitoring the movement of pebbles in real time according to claim 6, wherein: the pressure method in the step c is as follows:
the pressure method for calculating the pebble transport volume is to further convert the measured pressure data to obtain the pebble bed transport volume in a certain time period, and the methods for calculating the pebble transport volume comprise two methods: firstly, under the condition of short transportation time, the measured pressure data is the pebble stacking weight m in a period of time; secondly, under the condition of long-time transportation, the total transportation amount of pebbles is calculated through further data processing, and the specific calculation steps are mainly divided into four steps: firstly, setting the current return data and the next data of the instrument as X respectively1And X2；②X1And X2The difference is a single data return cycleThe weight of the eggs and gravels transported inwards; thirdly, calculating the weight m of the gravel in each data return period in the total transportation timei(ii) a Fourthly, the weight m of the pebbles in each data return periodiThe sum is the total mass m of the gravel in the total transportation time.
9. The image-based method for monitoring the movement of pebbles in real time according to claim 6, wherein: and c, acquiring data by a camera method according to the following principle, wherein when pebbles shoot an area through the camera (6), the camera (6) can directionally observe the pebbles passing through the upper panel to obtain a plurality of pebble images, splicing and fusing the images shot by the camera (6) after obtaining an original observation image, dividing the shot video into one frame of image, performing interframe difference on the images, restoring the form of the pebbles passing through the upper panel through matlab codes, and then calculating the size and particle size information.
10. An egg gravel transportation real-time monitoring system based on an image method is characterized by comprising the following steps: the monitoring device of any one of claims 1 to 5, and an electrical box or a computer terminal electrically connected with the monitoring device through a cable, wherein the electrical box or the computer terminal is arranged on shore.
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