Device and method for measuring content of runoff sediment based on three-dimensional vision and dynamic weighing

Abstract

The present application relates to a kind of runoff sediment content measuring device and method based on three-dimensional vision and dynamic weighing.The runoff sediment content measuring device includes inflow, water inlet valve, machine case, container, bottom plate, rack, drain valve, weighing sensor, universal support, water level electrode, control module and depth camera;The middle part of the bottom plate of the machine case is provided with an opening allowing the container to pass through;The outer surface of the container is circumferentially provided with a support plate, and a circular-arc-shaped mounting groove is arranged on the support plate;Three universal supports are circumferentially mounted on the support plate, and the lower end of each universal support is fixedly connected with a weighing sensor, and the weighing sensor is in contact with the bottom plate and fixed;Depth camera is used to obtain the three-dimensional depth image of the runoff surface in the container.The present application breaks through the precision bottleneck of non-steady-state liquid surface volume measurement, realizes high-precision mass measurement under the condition of shaking, and completely eliminates the mechanical interference of rotating runoff on the weighing sensor.

Description

Technical Field

[0001] This invention belongs to the field of soil and water conservation monitoring and hydrological monitoring technology, specifically relating to a device and method for measuring runoff sediment content based on three-dimensional vision and dynamic weighing under fluid fluctuation, turbulence and unsteady conditions. Background Technology

[0002] Accurate measurement of runoff sediment content is crucial for studying soil erosion, conducting watershed planning, and evaluating soil and water conservation benefits. Currently, the mainstream measurement devices are based on the "gravity method," which involves designing containers to collect surface runoff, measuring the total mass and volume of the runoff, and then calculating the sediment content.

[0003] However, existing automated measurement devices have significant drawbacks. First, after runoff flows into the container, the liquid surface exhibits irregular bulges and depressions. For example, the scheme in the invention patent application "A Constant-Volume Dual-Float Runoff Plot Sediment Content Measurement System" (application number: CN202510486458.0) uses floats to obtain a single-point water level. Other methods, such as laser sensors and ultrasonic sensors, also measure water levels in this way, failing to characterize the overall volume of fluctuating runoff and leading to significant calculation errors due to "representing the surface by a point." The measurement scheme in the invention patent application "A Machine Vision-Based Runoff Water Level and Sediment Content Measurement Device and Method" (application number: CN202510984424.4) uses a camera to capture a fluctuating liquid surface line at a certain angle to represent the runoff volume, resulting in measurement errors due to "representing the surface by a line." Second, the up-and-down fluctuations and rotations of runoff within the container generate vertical acceleration components, horizontal centrifugal forces, and frictional torque between the runoff and the container's inner wall. Lateral loads cause severe fluctuations in the weighing sensor readings, even malfunctioning the sensor, making it difficult to obtain accurate mass measurements. Third, if the measurement is taken after the liquid surface has settled, the real-time performance of the measurement is very poor, and the sediment has often already settled. The sediment is difficult to completely drain, resulting in cumulative errors in volume.

[0004] Therefore, there is a need for a monitoring device and method that can quickly, non-contactly, and accurately measure the total volume and mass of surface runoff while the liquid surface is fluctuating and the sediment has not yet settled. Summary of the Invention

[0005] The purpose of this invention is to provide a device and method for measuring runoff sediment content based on three-dimensional vision and dynamic weighing. It utilizes three-dimensional point clouds to solve the problem of fluctuating volume measurement and uses three-point adjustable center of gravity, universal support components and least squares curve fitting to solve the problem of dynamic mass measurement.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A device for measuring runoff sediment content based on three-dimensional vision and dynamic weighing includes an inlet, an inlet valve, a chassis, a container, a base plate, a frame, a drain valve, a weighing sensor, a universal support, a water level electrode, a control module, and a depth camera.

[0008] The bottom plate of the chassis is fixedly connected to the top of the frame; the bottom plate has an opening in the middle that allows a container to pass through; the container is used to collect the surface runoff to be measured, and its bottom drain outlet is equipped with a controlled drain valve; the top of the chassis is provided with an inlet to allow the runoff to flow into the container; the inlet valve is installed on the inlet to control the opening and closing of the inlet.

[0009] The outer surface of the container is provided with a support plate circumferentially, and the support plate has an arc-shaped mounting groove. Three universal supports are circumferentially mounted on the support plate, one of which is fixedly connected to the support plate on the side opposite to the arc-shaped mounting groove and located on the arc centerline of the arc-shaped mounting groove. The other two universal supports are adjustablely positioned within the arc-shaped mounting groove. The lower end of each universal support is fixedly connected to a weighing sensor, which is in contact with and fixed to the base plate. During installation, the installation positions of the two universal supports within the arc-shaped mounting groove are adjusted until the values ​​detected by all weighing sensors are consistent.

[0010] The depth camera is fixedly mounted on the top wall of the chassis directly above the container, with the lens pointing vertically downwards, to acquire a three-dimensional depth image of the flow pattern inside the container.

[0011] The water level electrode is located at a certain distance below the top of the container. When the runoff triggers the water level electrode, the external runoff stops flowing in. The control module is fixedly installed on the inner wall of the chassis and is connected to the weighing sensor, water level electrode, depth camera, drain valve and inlet valve. It is used to control the operation process and data acquisition and processing of the entire device.

[0012] The universal support is used to eliminate the centrifugal force and frictional torque generated by the rotation of the runoff. The upper ball seat of the universal support is fixedly installed to the support plate of the container by a nut, and the thread of the lower ball seat is directly screwed into the weighing sensor. The steel ball is connected to the upper ball seat and the lower ball seat through point contact.

[0013] The container is a cylindrical stainless steel drum with a diameter of 400 mm and a height of 500 mm.

[0014] The distance between the depth camera and the container is 500mm; the resolution of the depth camera is 640×480, and the depth measurement accuracy is ±0.5mm.

[0015] A method for measuring runoff sediment content based on three-dimensional vision and dynamic weighing using the aforementioned runoff sediment content measuring device includes the following steps:

[0016] S1, Quality Measurement

[0017] S1.1 Establishing the Fitting Curve

[0018] Formula 1

[0019] In formula 1, The total measurement value of the weighing sensor at time t, in grams; λ is the actual mass of the runoff after it comes to rest, in grams; A is the initial amplitude of the sloshing, in grams; λ is the damping coefficient; ω is the sloshing frequency. For phase;

[0020] S1.2, Least Squares Method

[0021] Adjusting Formula 1 A, λ, ω These five parameters minimize the sum of squared distances from the total measured value of each weighing sensor to the predicted curve, as expressed by the formula:

[0022] Formula 2

[0023] In formula 2, For t i The total mass measurement value of the weighing sensor at all times. For t i Quality prediction values ​​from the time-matter algorithm;

[0024] The algorithm will automatically and continuously fine-tune. A, λ, ω These five parameters are used until a set of parameters is found that minimizes the error value; at this point, the result is determined. It is the measured actual mass value of the runoff inside the container;

[0025] S2, Volume Measurement

[0026] Using a depth camera as the origin of the coordinate axis, point cloud data of the undulating liquid surface is acquired. The output of the point cloud data processing is the average depth from the depth camera to the undulating liquid surface. The liquid surface at this depth is the liquid surface when the runoff is still, as shown in Formula 3:

[0027] Formula 3

[0028] In formula 3, The average depth from the depth camera to the undulating liquid surface, in mm; The volume of space between the depth camera and the undulating liquid surface, in mm. 3 ; For camera to The depth of the location, in mm; for The area at the point is sufficiently small, in mm. 2 S represents the cross-sectional area of ​​the container, in mm². 2 ; The depth of a measurement point is expressed in mm; N represents the total number of points in the point cloud.

[0029] The specific steps for volume measurement are as follows:

[0030] S2.1 System Calibration

[0031] Different gradients of runoff were injected into the container, and after the liquid surface stabilized, the average depth of the static liquid surface was obtained using a depth camera. Establish a mathematical mapping model between the average depth of the camera and the liquid surface and the runoff volume. As shown in Formula 4:

[0032] Formula 4

[0033] In Formula 4, V is the runoff volume, in mL; is the average depth from the depth camera to the undulating liquid surface, in mm; k and b are parameters obtained through fitting multiple sets of experimental measurements.

[0034] S2.2, Volume Calculation Stage

[0035] A depth camera is used to acquire point cloud data images of the fluctuating liquid surface. The acquired depth images are denoised to remove the container walls and external background and extract the region of interest. Formula 3 is used to calculate the arithmetic mean of the depth of all effective pixels in the ROI region as the equivalent static depth of the current fluctuating liquid surface. This equivalent depth is then substituted into Formula 4 to calculate the total volume of the current runoff.

[0036] S3, Sediment content measurement

[0037] The surface runoff sediment content is calculated using Formula 5 based on the total mass and volume inside the container.

[0038] Formula 5

[0039] In Formula 5, M represents the total mass of runoff in grams (g); V represents the total volume of runoff in centimeters (cm³). 3 ; This is the density of water, expressed in g / cm³. 3 ; The density of sediment, expressed in g / cm³. 3 C represents the sediment content, in g / cm³. 3 .

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] 1. This invention overcomes the accuracy bottleneck in measuring the volume of unsteady liquid surfaces. Existing technologies typically use ultrasonic or radar level gauges for single-point measurements. When the liquid surface fluctuates violently or eddies are present, single-point data cannot represent the overall liquid level, leading to significant errors in volume calculation. This invention introduces three-dimensional point cloud data acquisition and utilizes the principles of fluid volume conservation and geometric complementarity. By calculating the arithmetic mean of the fluctuating liquid surface depth data, it mathematically provides an unbiased equivalent representation of the liquid level height after the fluid has settled. This allows the device to achieve high-precision instantaneous volume measurement even under conditions of violent flow fluctuations, without waiting for the liquid surface to settle, significantly improving the real-time performance of monitoring.

[0042] 2. Achieved high-precision mass measurement under swaying conditions. Existing technologies, under runoff impact and swaying conditions, result in weighing sensor readings exhibiting irregular jumps or large oscillations, making it difficult to obtain the true mass. This invention innovatively applies the least squares curve fitting algorithm to construct a physical model based on damped oscillations, performing iterative fitting and parameter inversion on unsteady weighing data sequences. This method can accurately extract the true mass from signals containing significant noise and dynamic interference. Compared to traditional simple averaging filtering, this method is insensitive to truncation errors and has stronger anti-interference capabilities and faster convergence speed, achieving accurate results even with short acquisition periods.

[0043] 3. Completely eliminates mechanical interference from rotating runoff in weighing sensors. When runoff flows into a container, it generates strong internal rotating eddies. The resulting centrifugal force and frictional torque act on the container wall, causing the traditional rigidly connected weighing sensor to twist, producing false readings or even damaging the sensor. This invention uses a three-point support structure that can automatically adapt to the horizontal shift of the center of gravity caused by fluid sloshing; the universal support component plays a mechanical decoupling role, effectively cutting off the transmission path of horizontal centrifugal force and torque to the sensor, ensuring that the sensor only senses the vertical gravity component, and guaranteeing the accuracy of dynamic weighing. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the structure of the runoff sediment content measuring device of the present invention;

[0045] Figure 2 This is a schematic diagram showing the arrangement of the weighing sensor of the present invention;

[0046] Figure 3 This is a cross-sectional view of the universal support component of the present invention;

[0047] Figure 4a This is a point cloud image of the fluctuating liquid surface collected in an embodiment of the present invention;

[0048] Figure 4b To extract the region of interest (ROI) image by removing the container wall and external background in this embodiment of the invention;

[0049] Figure 4c Average depth planar image of an embodiment of the present invention.

[0050] The reference numerals in the attached figures are:

[0051] 1 Inlet; 2 Water inlet valve; 3 Chassis; 4 Container; 5 Base plate; 6 Frame; 7 Drain valve; 8 Weighing sensor; 9 Universal support; 10 Hinge; 11 Water level electrode; 12 Control module; 13 Depth camera; 91 Upper ball seat; 92 Steel ball; 93 Lower ball seat; 94 Arc-shaped mounting slot. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0053] This invention provides a device for measuring runoff sediment content based on three-dimensional vision and dynamic weighing. (See reference...) Figure 1 The specific structure of the runoff sediment content measurement device based on three-dimensional vision and dynamic weighing is shown. The runoff sediment content measurement device includes an inlet 1, an inlet valve 2, a chassis 3, a container 4, a base plate 5, a frame 6, a drain valve 7, a weighing sensor 8, a universal support 9, a water level electrode 11, a control module 12, and a depth camera 13.

[0054] The chassis 3 is fixedly mounted on the frame 6 to protect against wind, water, and light, safeguarding the internal structure of the device and preventing external interference from affecting measurement accuracy. The bottom plate 5 of the chassis 3 is fixedly connected to the top of the frame 6. An opening in the middle of the bottom plate 5 allows the container 4 to pass through. The container 4 is used to collect the surface runoff to be measured, and its bottom drain outlet is equipped with a controlled drain valve 7. An inlet 1 is provided on the top of the chassis 3 to allow the runoff to flow into the container 4. A water inlet valve 2 is installed on the inlet 1 to control the opening and closing of the inlet 1. The front panel of the chassis 3 is mounted on the chassis 3 via a hinge 10.

[0055] like Figure 2As shown, the outer surface of the container 4 is circumferentially provided with a support plate, and the support plate has an arc-shaped mounting groove 94; three universal support members 9 are circumferentially mounted on the support plate, one of which is fixedly connected to the support plate on the side opposite to the arc-shaped mounting groove 94 and located on the arc centerline of the arc-shaped mounting groove 94; the other two universal support members 9 are adjustablely positioned within the arc-shaped mounting groove 94; the lower end of each universal support member 9 is fixedly connected to a weighing sensor 8, and the weighing sensor 8 is in contact with and fixed to the base plate 5. During installation, the installation positions of the two universal support members 9 within the arc-shaped mounting groove 94 are adjusted until the values ​​detected by all weighing sensors 8 are consistent.

[0056] The depth camera 13 is fixedly installed on the top wall of the casing 3 directly above the container 4, with the lens pointing vertically downwards, and is used to acquire a three-dimensional depth image of the flow pattern inside the container 4.

[0057] The water level electrode 11 is located 5 cm below the top of the container 4. When the runoff triggers the water level electrode 11, the external runoff stops flowing in. The control module 12 is fixedly installed on the inner wall of the casing 3 and is connected to the weighing sensor 8, the water level electrode 11, the depth camera 13, the drain valve 7, and the inlet valve 2. It is used to control the operation process and data acquisition and processing of the entire device.

[0058] See Figure 3 The universal support 9 is a key structure for ensuring weighing accuracy. It connects the load cell 8 to the container 4 and eliminates the centrifugal force and frictional torque generated by the rotation of the runoff. The upper ball seat 91 of the universal support 9 is fixedly installed to the support plate of the container 4 by a nut, and the thread of the lower ball seat 93 is directly screwed into the load cell 8. The steel ball 92 connects the upper ball seat 91 and the lower ball seat 93 through point contact. This design can accurately compensate for the flatness error of the external welded track of the collector, ensuring that each load cell is always in an ideal vertical stress state, avoiding measurement inaccuracies or sensor damage caused by lateral forces or bending moments. At the same time, this structure releases a certain degree of freedom, effectively buffering the impact vibration generated during runoff injection and pneumatic butterfly valve operation, improving the stability and accuracy of weighing data.

[0059] Preferably, the container 4 is a cylindrical stainless steel bucket with a diameter of 400 mm and a height of 500 mm.

[0060] Preferably, the distance between the depth camera 13 and the container 4 is 500mm; the resolution of the depth camera 13 is 640×480, and the depth measurement accuracy is ±0.5mm.

[0061] This invention also provides a method for measuring runoff sediment content based on three-dimensional vision and dynamic weighing, comprising the following steps:

[0062] S1, Quality Measurement

[0063] During mass measurement, although the structure of the universal support 9 eliminates the centrifugal force and torque of the internal flow of the container 4, the fluctuating liquid will generate acceleration in the vertical direction. Therefore, the measured mass is not a constant value, but rather a damped sine wave curve fluctuating around the true mass. Thus, this invention employs least squares curve fitting to determine the true mass, specifically including the following steps:

[0064] S1.1 Establishing the Fitting Curve

[0065] The runoff sloshing within container 4 is mechanically a classic damped harmonic oscillator model, and its actual physical laws follow the following formula:

[0066] Formula 1

[0067] In formula 1, The total measurement value of the weighing sensor at time t, in grams; λ is the actual mass of the runoff after it comes to rest, in grams; A is the initial amplitude of the sloshing, in grams; λ is the damping coefficient; ω is the sloshing frequency. For phase.

[0068] S1.2, Least Squares Method

[0069] Adjusting Formula 1 A, λ, ω These five parameters minimize the sum of squared distances from the total measured values ​​of each weighing sensor 8 to the predicted curve, as expressed by the formula:

[0070] Formula 2

[0071] In formula 2, For t i The total mass measurement value of the constant weighing sensor 8. For t i Quality prediction values ​​from the time-matter algorithm;

[0072] The algorithm will automatically and continuously fine-tune. A, λ, ω These five parameters are used until a set of parameters is found that minimizes the error value; at this point, the result is determined. It refers to the measured actual mass value of the runoff inside container 4.

[0073] S2, Volume Measurement

[0074] Once the runoff stops flowing into container 4, the total volume V remains constant regardless of the fluctuations. At this point, there must exist a plane such that the volume bulging above the plane can be cut to fill the volume concave below it. To find this plane, this invention uses depth camera 13 as the origin of the coordinate axis to acquire point cloud data of the fluctuating liquid surface. The output of the point cloud data processing is the average depth from depth camera 13 to the fluctuating liquid surface. The liquid surface at this depth is the liquid surface when the runoff is still, as shown in Formula 3:

[0075] Formula 3

[0076] In formula 3, The average depth from the depth camera to the undulating liquid surface, in mm; The volume of space between the depth camera and the undulating liquid surface, in mm. 3 ; For camera to The depth of the location, in mm; for The area at the point is sufficiently small, in mm. 2 S represents the cross-sectional area of ​​the container, in mm². 2 ; The depth of a measurement point is expressed in mm; N is the total number of point clouds.

[0077] The specific steps for volume measurement are as follows:

[0078] S2.1 System Calibration

[0079] Different gradients of runoff were injected into container 4. After the liquid surface stabilized, the average depth of the static liquid surface was obtained using a depth camera. Since the volume of container 4 is known, the runoff volume at different average depths can be determined, thus establishing a mathematical mapping model between the "camera-liquid surface average depth" and the "runoff volume". As shown in Formula 4.

[0080] Formula 4

[0081] In Formula 4, V is the runoff volume, in mL; The depth is the average depth from the depth camera to the undulating liquid surface, in mm; k and b are parameters obtained through fitting multiple sets of experimental measurements.

[0082] S2.2, Volume Calculation Stage

[0083] Use depth camera 13 to acquire point cloud data images of the fluctuating liquid surface (e.g.) Figure 4aAs shown), the acquired depth image is denoised to remove container walls and external background, and the region of interest (ROI) is extracted (e.g.). Figure 4b (As shown); use Formula 3 to calculate the arithmetic mean of the depths of all valid pixels within the ROI region, as the equivalent static depth of the current fluctuating liquid surface (e.g., Figure 4c (as shown); Substitute this equivalent depth into Formula 4 to calculate the total volume of the current runoff.

[0084] S3, Sediment content measurement

[0085] The surface runoff sediment content is calculated using Formula 5 based on the total mass and volume inside the container.

[0086] Formula 5

[0087] In Formula 5, M represents the total mass of runoff in grams (g); V represents the total volume of runoff in centimeters (cm³). 3 ; This is the density of water, expressed in g / cm³. 3 ; The density of sediment, expressed in g / cm³. 3 C represents the sediment content, in g / cm³. 3 .

[0088] Example

[0089] In this embodiment, the calibration area is set to a range of 3 cm above and below the water level electrode 11. 200 ml of water is gradually added to the container 4 from bottom to top, and the current actual volume is recorded. Then, depth camera 13 was used to capture point cloud data of the stationary liquid surface, and the average depth value of all point cloud values ​​for the stationary liquid surface was calculated. , Depth pixels. Repeat 3 times to obtain 3 sets of data pairs. The functional relationship in Formula 4 is then fitted. The position of the depth camera cannot be changed; if it is altered, recalibration is required.

[0090] Assume a heavy rainfall runoff event occurs, and the runoff flows into measuring container 4. When the runoff triggers the water level electrode 11, the inlet valve 2 closes. Two seconds later, the runoff inside container 4 is in a state of violent fluctuation and rotation. The system immediately initiates the measurement process:

[0091] Step S1, Mass Measurement

[0092] The load cell 8 acquires data at a high speed of 100Hz. Due to the up-and-down fluctuations of the water flow, the sensor readings exhibit a damped sinusoidal oscillation pattern.

[0093] Data Acquisition: To facilitate the explanation of the mass measurement principle, this paper lists the key data points collected and uses least-squares fitting to calculate the true mass. The original oscillation data collected by the weighing sensor are at time node t [0.5, 0.6, 0.75, 0.9] and mass m [20.85, 20.3, 19.95, 20.6]. The data shows that if read directly at this point, the mass fluctuates wildly between 19.95 kg and 20.85 kg, with a large error, but the true mass is hidden within these fluctuations.

[0094] The system invokes the built-in damped oscillation physical model:

[0095]

[0096] in, The true quality to be sought.

[0097] Least squares fitting process: The system uses the "least squares method" algorithm to iteratively find a set of optimal parameters. A, λ, ω The goal is to minimize the sum of squared residuals (error) between the model's predicted values ​​and the measured values ​​listed above.

[0098] First guess: The algorithm first guesses M = 20.42 (mean), A = 0.45 (maximum value - minimum value) / 2), and sets λ to 1; ω is given an empirical value of 2π. Set it to 0. Calculations show that the error (error=19.59) is very large, so further parameter adjustments are needed.

[0099] Intermediate correction: When the algorithm detects that the waveform does not match, it automatically adjusts the parameters, such as lowering M and increasing the frequency ω.

[0100] Final convergence: After several iterations, the fitting residual error < 0.001, and the algorithm finally locks in the optimal parameters as follows:

[0101] True quality =20.421kg; oscillation amplitude A=0.4kg; attenuation coefficient λ=0.8; that is, after removing the fluctuation interference, the true mass of the runoff is 20.421kg.

[0102] Step S2, Volume Measurement

[0103] Due to liquid surface fluctuations, it is impossible to directly read a single liquid level. This system utilizes a depth camera to measure the instantaneous three-dimensional shape of the entire liquid surface.

[0104] Data Acquisition: The camera captures a single frame of image. To facilitate the explanation of the volume measurement principle, this invention selects a simplified 3×3 depth pixel matrix (555,550,545,550,540,535,555,545,540) in the central region of the liquid surface as the simulated point cloud data for processing.

[0105] Calculate the average depth: The system calculates the arithmetic mean of the above point cloud depth values:

[0106]

[0107] According to the principle that the volume inside the container remains constant, the volume of the higher peaks fills the volume of the lower troughs. Therefore, the average depth of 546.11 mm is mathematically equivalent to the depth of the plane after the liquid surface is completely still.

[0108] Volume calculation: Based on the pre-calibrated formula, assuming the calibration formula is: Substituting the values ​​into the calculation, we get: .

[0109] Step S3: Measurement of sediment content

[0110] Based on the precise data obtained from the above two steps, combined with the density of water (1 kg / m³), 3 Soil density 2.65 kg / m³ 3 Substituting into the formula, we get:

[0111]

[0112] The system ultimately output the sediment content result for this measurement as 0.31 kg / m³. 3 The entire measurement was completed within 3 seconds. The system then opened the drain valve to empty the flow in the container, ready for the next measurement.

Claims

1. A device for measuring runoff sediment content based on three-dimensional vision and dynamic weighing, characterized in that, The runoff sediment content measuring device includes an inlet (1), an inlet valve (2), a chassis (3), a container (4), a base plate (5), a frame (6), a drain valve (7), a weighing sensor (8), a universal support (9), a water level electrode (11), a control module (12), and a depth camera (13). The bottom plate (5) of the chassis (3) is fixedly connected to the top of the frame (6); the bottom plate (5) has an opening in the middle that allows the container (4) to pass through; the container (4) is used to collect the surface runoff to be measured, and the drain outlet at its bottom is equipped with a controlled drain valve (7); the top of the chassis (3) is provided with an inlet (1) to allow the runoff to flow into the container (4); the water inlet valve (2) is installed on the inlet (1) to control the opening and closing of the inlet (1); The outer surface of the container (4) is provided with a support plate, and the support plate is provided with a section of arc-shaped mounting groove (94); three universal support members (9) are circumferentially mounted on the support plate, one of which is fixedly connected to the support plate on the side opposite to the arc-shaped mounting groove (94) and located on the arc center line of the arc-shaped mounting groove (94); the other two universal support members (9) are installed in the arc-shaped mounting groove (94) with adjustable installation positions; the lower end of each universal support member (9) is fixedly connected to a weighing sensor (8), and the weighing sensor (8) is in contact with and fixed to the base plate (5); during installation, the installation positions of the two universal support members (9) in the arc-shaped mounting groove (94) are adjusted until the values ​​detected by all weighing sensors (8) are consistent; The depth camera (13) is fixedly installed on the top wall of the chassis (3) directly above the container (4), with the lens pointing vertically downward, for acquiring a three-dimensional depth image of the flow inside the container (4); The water level electrode (11) is set at a certain distance below the top of the container (4). When the runoff triggers the water level electrode (11), the external runoff stops flowing in. The control module (12) is fixedly installed on the inner wall of the chassis (3) and connected to the weighing sensor (8), water level electrode (11), depth camera (13), drain valve (7) and inlet valve (2) to control the operation process and data acquisition and processing of the entire device.

2. The runoff sediment content measuring device according to claim 1, characterized in that, The universal support (9) is used to eliminate the centrifugal force and frictional torque generated by the rotation of the runoff. The upper ball seat (91) of the universal support (9) is fixedly installed with the support plate of the container (4) by a nut. The thread of the lower ball seat (93) is directly screwed into the weighing sensor (8). The steel ball (92) is connected to the upper ball seat (91) and the lower ball seat (93) by point contact.

3. The runoff sediment content measuring device according to claim 1, characterized in that, The container (4) is a cylindrical stainless steel barrel with a diameter of 400 mm and a height of 500 mm.

4. The runoff sediment content measuring device according to claim 1, characterized in that, The distance between the depth camera (13) and the container (4) is 500mm; the resolution of the depth camera (13) is 640×480, and the depth measurement accuracy is ±0.5mm.

5. A method for measuring runoff sediment content based on three-dimensional vision and dynamic weighing using the runoff sediment content measuring device as described in any one of claims 1-4, characterized in that, The method includes the following steps: S1, Quality Measurement S1.1 Establishing the Fitting Curve Official 1 In formula 1, The total measurement value of the weighing sensor at time t, in grams; This represents the actual mass of the runoff after it has come to rest, in grams. A is the initial amplitude of the sway, in g; λ is the damping coefficient; ω is the sway frequency; For phase; S1.2, Least Squares Method Adjusting Formula 1 A, λ, ω These five parameters minimize the sum of squared distances from the total measured value of each weighing sensor (8) to the predicted curve, as expressed by the formula: Official 2 In formula 2, For t i The total mass measurement value of the weighing sensor (8) at all times. For t i Quality prediction values ​​from the time-matter algorithm; The algorithm will automatically and continuously fine-tune. A, λ, ω These five parameters are used until a set of parameters is found that minimizes the error value; at this point, the result is determined. This refers to the actual mass value of the runoff inside the container (4) being measured; S2, Volume Measurement Using the depth camera (13) as the origin of the coordinate axis, point cloud data of the undulating liquid surface is acquired. The output of the point cloud data processing is the average depth from the depth camera (13) to the undulating liquid surface. The liquid surface at this depth is the liquid surface when the runoff is still, as shown in Formula 3: Official 3 In formula 3, The average depth from the depth camera to the undulating liquid surface, in mm; The volume of space between the depth camera and the undulating liquid surface, in mm. 3 ; For camera to The depth of the location, in mm; for The area at the point is sufficiently small, in mm. 2 S represents the cross-sectional area of ​​the container, in mm². 2 ; The depth of a measurement point is expressed in mm; N represents the total number of points in the point cloud. The specific steps for volume measurement are as follows: S2.1 System Calibration Different gradients of runoff were injected into container (4), and after the liquid surface stabilized, the average depth of the static liquid surface was obtained using a depth camera. Establish a mathematical mapping model between the average depth of the camera and the liquid surface and the runoff volume. As shown in Formula 4: Official 4 In Formula 4, V is the runoff volume, in mL; is the average depth from the depth camera to the undulating liquid surface, in mm; k and b are parameters obtained through fitting multiple sets of experimental measurements. S2.2, Volume Calculation Stage A depth camera (13) was used to collect point cloud data images of the fluctuating liquid surface. The collected depth images were denoised, and the container wall and external background were removed to extract the region of interest. Use Formula 3 to calculate the arithmetic mean of the depths of all valid pixels within the ROI region, which is taken as the equivalent static depth of the current fluctuating liquid surface; substitute this equivalent depth into Formula 4 to calculate the total volume of the current runoff. S3, Sediment content measurement The surface runoff sediment content is calculated using Formula 5 based on the total mass and volume inside the container. Official 5 In Formula 5, M represents the total mass of runoff in grams (g); V represents the total volume of runoff in centimeters (cm³). 3 ; This is the density of water, expressed in g / cm³. 3 ; The density of sediment, expressed in g / cm³. 3 C represents the sediment content, in g / cm³. 3 .

Images