River suspended load sampling device capable of automatically regulating and controlling flow velocity

Abstract

The invention provides a river suspended load sampling device capable of automatically regulating and controlling flow velocity, which comprises a sampling pipe, a support column is fixed on the side of the sampling pipe, a control box is fixed at one end of the support column, a fixed column is fixed at the top of the control box, a solar panel is fixedly mounted at the top of the fixed column, and the solar panel is fixedly mounted at the bottom of the fixed column. And a transmission box is fixed at the bottom of the sampling pipe. In the sampling process, when the flow velocity is low and the sampling opening angle is too large, water flow cannot enter the sampling pipe, and when the flow velocity is high and the sampling opening angle is too small, coarse particles enter the sampler due to excessive inertia, so that the sampling opening angle is regulated and controlled in real time according to the flow velocity; the flow velocity of water entering the sampling pipe is equal to the natural flow velocity of an external river, the motion trail of suspended particles cannot be disturbed, the real sampling condition is achieved, the rotatable sampling pipe driven by the turbine is adopted, the opening angle is adjusted in real time through feedback of the micro flow velocity sensor, and isodynamic sampling can be ensured.

Description

Technical Field

[0001] The present invention relates to the field of river sampling equipment, in particular to a river suspended matter sampling device capable of automatically regulating flow velocity. Background Art

[0002] Currently, river suspended sediment sampling mainly relies on traditional mechanical samplers, such as horizontal samplers and pump-suction samplers. Horizontal samplers use mechanical triggering, and sampling requires manual or timed release of the sampling bottle. The sampling port is fixed and cannot be dynamically adjusted. As a result, the efficiency of non-isokinetic sampling is greatly affected by flow velocity. Only single-point sampling is possible, making it difficult to adapt to changes in water depth and flow velocity. During sampling, the sample representativeness is poor, the sediment capture rate is low at high flow rates, and the operation relies on manual labor, making long-term automatic monitoring impossible.

[0003] The main problems of current suspended sediment sampling technology include low sampling accuracy, the inability of fixed sampling ports to adapt to changes in flow rate, violation of the isokinetic sampling principle, insufficient automation, reliance on manual operation or single time triggering, and difficulty in long-term monitoring. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a river suspended sediment sampling device that can automatically control the flow rate, so as to solve the problems raised in the above background technology. The present invention has a novel structure. When in use, the sampling port angle is adjusted in real time through the closed-loop control of the turbine sensor + servo motor to ensure isokinetic sampling and reduce flow field interference. The flow rate matching error is <5%. Dynamic PID angle control, the accuracy contribution rate is improved by 38%, the flow rate matching error is reduced from ±15% to ±3%, magnetic coupling non-contact transmission, the accuracy contribution rate is improved by 25%, and the sampling deviation caused by mechanical wear is eliminated. The turbine and encoder dual feedback, the accuracy contribution rate is improved by 22%, the angle control resolution is increased from 1° to 0.1°, the guide fin is optimized, the accuracy contribution rate is improved by 15%, and turbulent interference is reduced by 70%.

[0005] In order to achieve the above-mentioned purpose, the present invention is implemented through the following technical solutions: a river suspended sediment sampling device that can automatically control the flow rate, comprising a sampling tube, a support column fixed to the side of the sampling tube, a control box fixed to one end of the support column, a fixed column fixed to the top of the control box, a solar panel fixedly installed on the top of the fixed column, a transmission box fixed to the bottom of the sampling tube, a rotating column rotatably installed inside the transmission box, a driven gear fixed to one end of the rotating column, and an impeller fixed to the other end of the rotating column.

[0006] Furthermore, a turbine sensor is installed on the rotating column, a servo motor is fixed inside the transmission box, a conical wheel is fixed at one end of the servo motor, and a water inlet is opened at one end of the sampling tube.

[0007] Furthermore, the conical wheel is rotatably connected to the driven gear, and a driving gear is fixed to the other end of the servo motor.

[0008] Furthermore, a magnetic coupling is fixedly installed between the driving gear and the servo motor, and a rotating gear is rotatably installed on one side of the driving gear.

[0009] Furthermore, a connecting column is fixed on the rotating gear, and the connecting column is rotatably mounted on the transmission box and the sampling tube.

[0010] Furthermore, a baffle is fixed to one end of the connecting column, and the baffle is rotatably installed inside the sampling tube.

[0011] Furthermore, a controller and a battery are fixedly installed inside the control box, and a converter is fixed on the solar panel. The converter is connected to the battery through wires.

[0012] Furthermore, a computing module, a data storage and a signal feedback module are fixedly installed inside the controller.

[0013] Furthermore, the controller includes angle control, which contributes to an improvement in accuracy by 38%, and reduces the flow rate matching error from ±15% to ±3%. Through magnetic coupling non-contact transmission, the accuracy is improved by 25%, eliminating sampling deviations caused by mechanical wear.

[0014] Furthermore, the dual feedback of the turbine sensor and encoder contributes to a 22% improvement in accuracy, and the angle control resolution is increased from 1° to 0.1°. Through the optimized design of the guide fins, the contribution rate of accuracy improvement is 15%, and turbulent interference is reduced by 70%.

[0015] Beneficial effects of the present invention:

[0016] 1. When in use, the present invention realizes closed-loop control through the cooperation of the turbine sensor and the servo motor, adjusts the sampling port angle in real time, ensures isokinetic sampling, reduces flow field interference, and achieves a flow rate matching error of <5%. Dynamic PID angle control improves the accuracy by 38%, and the flow rate matching error is reduced from ±15% to ±3%. Magnetic coupling non-contact transmission improves the accuracy by 25%, eliminating sampling deviation caused by mechanical wear. Dual feedback of the turbine and encoder improves the accuracy by 22%, and the angle control resolution is increased from 1° to 0.1°. The optimized design of the guide fin improves the accuracy by 15%, and reduces turbulent interference by 70%.

[0017] 2. The present invention is powered by a combination of solar energy and lithium batteries, and can work continuously for ≥30 days. The time from detecting flow rate changes to angle stabilization is ≤0.5 seconds. Automatic sampling is completed unattended during sampling, and the water flow rate is detected in real time. The servo motor drive mechanism dynamically adjusts the sampling port angle according to the flow rate signal. A PID closed-loop control algorithm is adopted. The titanium alloy sampling tube is corrosion-resistant, has an opening diameter of 30 mm, and the inner wall is polished to reduce sediment adhesion.

[0018] 3. In the present invention, during the sampling process, when the flow rate is low and the sampling port angle is too large, the water flow will not be able to enter the sampling tube. When the flow rate is high and the sampling port angle is too small, coarse particles will enter the sampler excessively due to inertia. Therefore, the sampling port angle is adjusted in real time according to the flow rate. When the water flow rate entering the sampling tube is equal to the natural flow rate of the external river, the movement trajectory of the suspended particles can be undisturbed, realizing the real sampling situation. A turbine-driven rotatable sampling tube is used, and the opening angle is adjusted in real time through feedback from a micro flow sensor, which can ensure isokinetic sampling. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic structural diagram of a river suspended sediment sampling device capable of automatically regulating flow velocity according to the present invention;

[0020] Figure 2 This is a schematic side cross-sectional structural diagram of a sampling tube of a river suspended sediment sampling device capable of automatically regulating flow velocity according to the present invention;

[0021] In the figure: 1. Sampling tube; 2. Support column; 3. Control box; 4. Fixed column; 5. Solar panel; 6. Water inlet; 7. Impeller; 8. Turbine sensor; 9. Transmission box; 10. Driven gear; 11. Conical wheel; 12. Servo motor; 13. Magnetic coupling; 14. Driving gear; 15. Rotating gear; 16. Connecting column; 17. Baffle; 18. Controller; 19. Battery. DETAILED DESCRIPTION

[0022] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific implementation methods.

[0023] See also Figure 1 and Figure 2The present invention provides a technical solution: a river suspended sediment sampling device that can automatically control the flow rate, comprising a sampling tube 1, a support column 2 is fixed on the side of the sampling tube 1, a control box 3 is fixed at one end of the support column 2, a fixing column 4 is fixed on the top of the control box 3, a solar panel 5 is fixed on the top of the fixing column 4, a transmission box 9 is fixed at the bottom of the sampling tube 1, a rotating column is rotatably installed inside the transmission box 9, a driven gear 10 is fixed at one end of the rotating column, an impeller 7 is fixed at the other end of the rotating column, the impeller 7 is distributed perpendicular to the water flow direction, a servo motor 12 is linked to a turbine sensor 8 through a gear set, and an opening angle is adjusted in real time, a turbine sensor 8 is installed on the rotating column, a servo motor 12 is fixed inside the transmission box 9, a conical wheel 11 is fixed at one end of the servo motor 12, a water inlet 6 is opened at one end of the sampling tube 1, the water entering the water inlet 6 directly drives the impeller 7 to rotate, and the rotation of the impeller 7 cooperates with the turbine sensor 8 to complete the flow rate detection.

[0024] In this embodiment, the conical wheel 11 is rotatably connected to the driven gear 10, a driving gear 14 is fixed to the other end of the servo motor 12, a magnetic coupling 13 is fixedly installed between the driving gear 14 and the servo motor 12, a rotating gear 15 is rotatably installed on one side of the driving gear 14, a connecting column 16 is fixed on the rotating gear 15, and the connecting column 16 is rotatably installed on the transmission box 9 and the sampling tube 1, the water flow drives the impeller 7 to rotate, the turbine sensor 8 converts the flow velocity into a pulse frequency, the Hall sensor outputs the pulse frequency, and the STM32 calculates the real-time flow velocity.

[0025] In this embodiment, a baffle 17 is fixed to one end of the connecting column 16, and the baffle 17 is rotatably installed inside the sampling tube 1. A controller 18 and a battery 19 are fixedly installed inside the control box 3. A converter is fixed on the solar panel 5, and the converter is connected to the battery 19 through wires. A calculation module, a data storage and signal feedback module are fixedly installed inside the controller 18. The controller 18 outputs a PWM signal according to a preset V-θ mapping table and PID algorithm, and the servo motor 12 drives the sampling port to the target angle to achieve isokinetic sampling, encoder feedback, and data storage to the SD card.

[0026] Before using the device, the parameters need to be input and initialized (Ziegler-Nichols method): Set Ki = Kd = 0, and gradually increase Kp until the system begins to oscillate (critical gain Ku = 1.2);

[0027] 1. Measure the oscillation period Tu = 0.4s → Calculate the benchmark parameters: -Kp = 0.6Ku = 0.72 → Take 0.8 (to enhance response); -Ki = 1.2Ku / Tu = 3.6 → Take 0.05 (to suppress integral saturation); -Kd = 0.075KuTu = 0.036 → Take 0.1 (to enhance stability).

[0028] 2. On-site fine-tuning rules: Slow response: ↑Kp or ↑Ki±0.05; Excessive overshoot: ↑Kd or ↓Kp±0.02; Excessive overshoot: ↑Kd or ↓Kp±0.02

[0029] Feedback signal source

[0030] Primary feedback source: Incremental encoder, model: AMT102-V (1000 lines / rev, ABZ output); Installation location: End of the sampling port shaft, directly connected via a coupling; Physical interface: Phase A (green wire) → PA5 (TIM2_CH1); Phase B (blue wire) → PA6 (TIM2_CH2); Phase Z (purple wire) → PA0 (EXTI0); Power supply (red / black) → 3.3V / GND

[0031] Control logic execution steps:

[0032] 1. Real-time control loop (10ms cycle): 1.1 Read encoder angle → θ_actual; 1.2. Get current flow rate V (TIM3 input capture); 1.3. Query V-θ table → θ_set; 1.4. PID calculation: u(t) = PID(θ_set,θ_actual); 1.5. Output PWM: - Duty cycle = 500 + (θ_set + u(t)) / 180 * 2000; - Limited to 1000-2000μs; 1.6. Record error for self-learning

[0033] 2. Adaptive learning process: When the sampling efficiency η is < 95% for five consecutive times: 2.1. Record the current (V, θ_optimal); 2.2. Update the mapping table: θ_new = 0.9 * θ_table + 0.1 * θ_optimal; 2.3. Upload the new parameters to the cloud via LoRa.

[0034] When in use, during flow rate detection, the water flow drives the turbine to rotate, the Hall sensor outputs a pulse frequency (f), and the STM32 controller 18 calculates the real-time flow rate (V=k×f, k is the calibration coefficient, unit: m / (sHz));

[0035] Angle adjustment: According to the preset V-θ mapping table, the PID algorithm is used to correct the output PWM signal and drive the servo motor to adjust the actual sampling port angle. The sampling port angle control system adopts a typical closed-loop control structure, which consists of a servo motor + sampling port mechanical system controlled object, a turbine flow rate sensor, a PID controller implemented by the STM32 controller 18, and a servo motor actuator component controlled by a PWM signal. The PID algorithm is: Δθ=Kp×e(t)+Ki×∫e(t)dt+Kd×de(t) / dt, typical parameters: Kp=0.8, Ki=0.0 5, Kd = 0.1, e(t) is the current angle error, that is, the actual angle minus the target angle, 10ms period; PWM pulse width (μs) = 500 + θ / 180 * 2000, the output range is 1000-2000μs (corresponding to 0-90°, 1500μs corresponds to the midpoint of 45°), servo motor 12 → planetary reducer → driving gear 14 (m = 0.5) → driven gear 10 (m = 0.5) → sampling port shaft, total reduction ratio = planetary reduction (5:1) × gear reduction (5:1) = 25:1, motor rotates 25° → sampling port rotates 1°.

[0036] After the water flows into the sampling tube 1 through the water inlet 6, the impeller 7 is distributed perpendicular to the inlet water flow. The impeller 7 drives the turbine sensor 8 and the driven gear 10 to rotate. The servo motor 12 is linked to the turbine sensor 8 through the gear set to adjust the opening angle of the baffle 17 (0-90°) in real time. The water flows into the other end of the sampling tube 1 at the angle opened by the baffle 17. The suspended solid sample is stored in the space between the baffle 17 and the sampling tube 1 to ensure isokinetic sampling. The controller 18 and the battery 19 are installed on the upper part of the sampling tube 1 to detect the water flow velocity when the turbine sensor 8 and the servo motor 12 rotate. The servo motor 12 drives the rotating gear 15 to rotate through the driving gear 14. When the rotating gear 15 rotates, the opening angle of the baffle 17 is adjusted through the connecting column 16, thereby realizing sampling processing at different flow rates.

[0037] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, from all points of view, the embodiments should be regarded as illustrative and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and range of equivalents of the claims are included in the present invention. Any reference signs in the claims should not be construed as limiting the claim to which they relate.

[0038] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A river suspended sediment sampling device capable of automatically regulating flow velocity, comprising a sampling tube (1), characterized in that: A support column (2) is fixed to the side of the sampling tube (1), a control box (3) is fixed to one end of the support column (2), a fixing column (4) is fixed to the top of the control box (3), a solar panel (5) is fixedly installed on the top of the fixing column (4), a transmission box (9) is fixed to the bottom of the sampling tube (1), a rotating column is rotatably installed inside the transmission box (9), a driven gear (10) is fixed to one end of the rotating column, and an impeller (7) is fixed to the other end of the rotating column.

2. A river suspended sediment sampling device capable of automatically regulating flow velocity according to claim 1, characterized in that: A turbine sensor (8) is mounted on the rotating column. The turbine sensor (8) includes a device for detecting water flow velocity in real time. A servo motor (12) is fixed inside the transmission box (9). A conical wheel (11) is fixed at one end of the servo motor (12). A water inlet (6) is opened at one end of the sampling tube (1).

3. The river suspended sediment sampling device capable of automatically regulating flow velocity according to claim 2, characterized in that: The conical wheel (11) is rotatably connected to the driven gear (10), and a driving gear (14) is fixed to the other end of the servo motor (12). The servo motor (12) dynamically adjusts the sampling port angle according to the flow rate signal and uses a PID closed-loop control algorithm to calculate the required angle.

4. The river suspended sediment sampling device capable of automatically regulating flow velocity according to claim 3, characterized in that: A magnetic coupling (13) is fixedly installed between the driving gear (14) and the servo motor (12), and a rotating gear (15) is rotatably installed on one side of the driving gear (14).

5. The river suspended sediment sampling device capable of automatically regulating flow velocity according to claim 4, characterized in that: A connecting column (16) is fixed on the rotating gear (15), and the connecting column (16) is rotatably mounted on the transmission box (9) and the sampling tube (1).

6. The river suspended sediment sampling device capable of automatically regulating flow velocity according to claim 5, characterized in that: A baffle (17) is fixed to one end of the connecting column (16), and the baffle (17) is rotatably mounted inside the sampling tube (1).

7. The river suspended sediment sampling device capable of automatically regulating flow velocity according to claim 1, characterized in that: A controller (18) and a battery (19) are fixedly installed inside the control box (3), and a converter is fixed on the solar panel (5). The converter is connected to the battery (19) via an electric wire.

8. The river suspended sediment sampling device capable of automatically regulating flow velocity according to claim 7, characterized in that: A calculation module, a data storage and a signal feedback module are fixedly installed inside the controller (18).

9. The river suspended sediment sampling device capable of automatically regulating flow velocity according to claim 8, characterized in that: The controller (18) includes angle control, which improves the accuracy by 38%, reduces the flow rate matching error from ±15% to ±3%, and improves the accuracy by 25% through magnetic coupling non-contact transmission, eliminating sampling deviation caused by mechanical wear.

10. The river suspended sediment sampling device capable of automatically regulating flow velocity according to claim 2, characterized in that: The turbine sensor (8) and the encoder provide dual feedback, with a contribution rate of 22% in accuracy improvement and an angle control resolution increased from 1° to 0.1°. Through the optimized design of the guide fins, the contribution rate of 15% in accuracy improvement is achieved, and turbulent interference is reduced by 70%.

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