Capacitive rice side deep fertilization flow monitoring device

Abstract

The utility model provides a kind of capacitive rice side deep fertilization flow monitoring device, including: capacitive fertilizer flow sensor, information processing system and conduit joint with calibration fertilizer outlet respectively arranged in its two sides, wherein: conduit joint is arranged outside capacitive fertilizer flow sensor by capacitive conduit gasket, capacitive fertilizer flow sensor is connected with information processing control system arranged in circuit installation box, fertilizer flows into conduit joint and capacitive fertilizer flow sensor directly generates electric signal from fertilizer outlet, control system obtains the calibration information of fertilizer after processing electric signal, and the amount of fertilization is adjusted after judging.This application can realize the real-time automatic calibration of field measurement fitting formula relationship curve according to different fertilizer types and temperature and humidity, greatly improve the environmental adaptability and accuracy of fertilizer monitoring. Realize the functions of fertilizer flow calibration, monitoring and leakage alarm of rice side deep fertilization, provide feedback data for closed-loop control of fertilization.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of agricultural automation, and particularly relates to a capacitive rice side deep fertilization flow monitoring device. BACKGROUND

[0002] The rice side deep variable fertilization needs to monitor the fertilization flow in real time, and on this basis, the electric or air-assisted fertilizer distributor is controlled in a closed loop, and the existing planar parallel plate capacitor fertilizer flow sensor has a small gap between the plates, which can easily cause fertilization blockage; the circular arc plate fertilizer flow capacitor sensor can realize the blockage or empty pipe detection of the fertilizer discharge pipe, but cannot realize real-time quantitative detection, and cannot meet the real-time monitoring requirements of the fertilizer flow of precision variable fertilization. SUMMARY

[0003] The present application is directed to the lack of effective fertilizer flow monitoring device in the existing rice side deep fertilization technology, and the difficulty in accurately controlling the fertilization amount according to the fertilization prescription and the forward speed before operation, and proposes a symmetrical circular arc plate capacitive rice side deep fertilization flow monitoring device, which has a large fertilizer flow channel aperture and can effectively avoid fertilization blockage; at the same time, the on-site real-time automatic calibration of the measured fitting formula relationship curve can be realized according to the different types of fertilizers and temperature and humidity, which greatly improves the environmental adaptability and accuracy of the fertilizer monitoring. The fertilizer flow calibration, monitoring and leakage alarm functions of the rice side deep fertilization are realized, and feedback data is provided for the closed-loop control of fertilization.

[0004] The present application is realized by the following technical solutions:

[0005] The present application relates to a symmetrical circular arc plate capacitive rice side deep fertilization flow monitoring device, comprising: a capacitive fertilizer flow sensor, an information processing system and a conduit joint with a calibration fertilizer injection port arranged on both sides thereof, wherein: the conduit joint is arranged outside the capacitive fertilizer flow sensor through a capacitive conduit gasket, the capacitive fertilizer flow sensor is connected with the information processing control system arranged in the circuit installation box, the fertilizer flows into the conduit joint and the capacitive fertilizer flow sensor from the fertilizer injection port to directly generate an electric signal, the control system processes the electric signal to obtain calibration information of the fertilizer, and the fertilization amount is adjusted after judgment.

[0006] The capacitive fertilizer flow sensor comprises: a pair of symmetrically arranged circular arc capacitive plates, specifically: two symmetrically arranged circular arc copper sheets with a radius R, a central angle , a thickness h and a length L, which are fixedly arranged on the sensor shell, wherein: R.

[0007] The capacitive detection formula of the capacitive fertilizer flow sensor is , wherein: V is the space volume surrounded by the two symmetric circular arc plates, V is the volume occupied by the fertilizer in V, V is the volume occupied by the air in V; εr is the relative dielectric constant of the fertilizer, εr is the relative dielectric constant of the air; θ is the central angle corresponding to the arc length of the circular arc electrode plate.

[0008] The calibration information of the fertilizer is specifically obtained by the following method: G Wherein: G is the measured mass of the fertilizer, C is the measured capacitance, and a and b are fitting coefficients obtained by least square fitting.

[0009] The adjustment of the fertilization amount includes:

[0010] Step 1, on-site real-time calibration measurement: a calibration feeding port is opened on one side of the fertilizer inlet pipe on the upper side of the sensor, different types and typical water contents of fertilizers are taken in the range of fertilizer discharge amount, and 5 seconds of different fertilizer discharge amounts n are taken, respectively, and the corresponding mass and corresponding capacitance value integral are recorded, and linear fitting is carried out according to the least square method;

[0011] Step 2, establish the corresponding relationship of the flow quality and the capacitance fitting formula of different fertilizer types and water contents in the vehicle-mounted upper monitoring interface, select the fertilizer type and water content in actual application, and the upper computer program automatically matches and detects the fitting formula.

[0012] Technical effects

[0013] The present application can realize real-time quantitative detection of fertilization flow quality, and break the original only blocking and emptying monitoring alarm; at the same time, different fertilizer types, different water contents of fertilizer amount have self-adaptive correction selection algorithm, which can meet the real-time monitoring of fertilization amount in the diversity environment of farmland field, provide real-time precision detection for rice side deep fertilization, and provide information guarantee for precision variable fertilization. DETAILED DESCRIPTION

[0014] Figure 1 It is a structural schematic diagram of the present application;

[0015] Figure 2 It is a schematic diagram of the capacitance type fertilizer flow sensor;

[0016] Figure 3 It is Figure 1 Explosive schematic diagram;

[0017] Figure 4 It is a flow chart of the embodiment;

[0018] Figure 5 It is a sectional view of the present application;

[0019] In the diagram: 1. Conduit connector; 2. Fertilizer inlet; 3. Conduit connector gasket; 4. Arc-shaped capacitor box; 5. Circuit mounting box; 6. Lower interface of capacitor conduit; 7. Arc-shaped capacitor plate; 8. Insulating nylon shell; 9. Capacitor connection circuit; 10. Side plate. Detailed Implementation

[0020] like Figures 1-3 As shown in this embodiment, a capacitive rice side-deep fertilization flow monitoring device includes: a capacitive fertilizer flow sensor, a circuit mounting box 5 respectively disposed on both sides of the sensor, and a conduit connector 1 with a calibrated fertilizer inlet 2. One end of the conduit connector 1 is connected to the upstream fertilizer discharge pipe through a corrugated pipe, and the other end is disposed outside the capacitive fertilizer flow sensor through a capacitive conduit gasket 3. The capacitive fertilizer flow sensor is connected to a control system disposed in the circuit mounting box 5. Fertilizer flows from the upstream fertilizer discharge pipe into the conduit connector 1 and the capacitive fertilizer flow sensor, directly generating an electrical signal. The control system performs linear fitting processing on the electrical signal to obtain the fertilizer flow quality information, and adjusts the fertilization amount based on the result.

[0021] like Figure 2 As shown, the capacitive fertilizer flow sensor includes: an arc-shaped capacitor box 4, two opposing arc-shaped capacitor plates 7, and an insulating nylon shell 8, wherein: the arc-shaped capacitor plates 7 are fixedly installed inside the arc-shaped capacitor box 4 through the insulating nylon shell 8.

[0022] The conduit connector 2 is corrugated and is connected to the upstream fertilizer conveying pipe through the corrugations.

[0023] The conduit connector gasket 3 is connected to the arc-shaped capacitor box 4 of the capacitive fertilizer flow sensor by screws and nuts.

[0024] The radius of the arc-shaped capacitor plate 7 is 10mm, and the central angle is... length mm, thickness is 0.1 mm.

[0025] Because fertilizer and air have different relative permittivity, when fertilizer passes through a capacitive sensor, the permittivity between the capacitor plates changes, causing the output capacitance value to change. The change in capacitance value is linearly related to the fertilizer flow rate within a certain range, and the instantaneous flow rate of fertilizer can be determined using least squares geometry.

[0026] When fertilizer passes through the arc-shaped capacitor plates, the dielectric constant of the sensor is [value missing], and the dielectric constant of the plates is [value missing]. The capacitance value of the plate is ,in: The volume occupied by fertilizer. V represents the volume occupied by air, and V is the volume of the space enclosed by the two symmetrical circular arc plates, in mm.3 , , is the relative dielectric constant of the fertilizer, , is the relative dielectric constant of the air, , is the half opening angle of the circular arc electrode plate, , is the central angle corresponding to the circular arc of the circular arc electrode plate, and the instantaneous total amount of fertilizer flowing through G is obtained by combining the empirical formula , a and b are different for different types of fertilizers and different environmental temperature and humidity, and the fitting needs to be recalibrated when the type of fertilizer and the temperature and humidity change.

[0027] As shown in Figure 3 and Figure 4 , the control system is arranged in the circuit installation box 5, including: a capacitance-voltage (C-V) conversion circuit, an in-situ fertilizer amount information processing circuit and an information output circuit, wherein: the capacitance-voltage (C-V) conversion circuit is connected with the two electrodes of the capacitive fertilizer flow sensor, and performs charging and discharging excitation and capacitance acquisition on the capacitor plate, and converts the capacitance information into a voltage signal and sends it to the upper computer, the in-situ fertilizer amount information processing circuit performs noise reduction processing on the voltage signal and then performs calibration processing, and the information output circuit uploads the calibration result to the upper computer to realize fertilizer leakage alarm.

[0028] The noise reduction processing refers to that the in-situ fertilizer amount information processing circuit obtains the base signal by sampling and averaging the content value of the time period during which no fertilizer flows. The effective capacitance during the subsequent fertilizer flow is described as , wherein is the real-time output value of the capacitance sensor.

[0029] The calibration processing refers to the compensation calibration of the type of fertilizer, temperature and humidity, specifically: according to the usual unit time fertilizer amount (g / s) requirement range, take n different fertilizer amount requirements in a short time t ), respectively, through the fertilizer amount of n times t in the range, respectively, through the calibration hole into the touch sensor, record the corresponding capacitance value, according to the n voltage-fertilizer quality relationship data, through the least square fitting to obtain the voltage-seeding amount relationship fitting, and store in the upper computer monitoring system.

[0030] The fertilizer leakage alarm refers to comparing the calibration result of each flow monitoring device with the threshold value, and when the fertilizer amount is lower than the threshold value, the fertilizer leakage alarm is performed.

[0031] The embodiment works by the following way: after the start of fertilization, the operator starts the machine, selects the corresponding fertilizer type and moisture content on the host computer interface, the fertilizer flows into the symmetric circular arc type plate capacitor fertilizer flow sensor of the application through the fertilizer inflow guide pipe, the fertilizer flow introduced by the pipe joint 1 passes through the circular arc capacitor plate 7, the change of the capacitance value caused by the change of the capacitance constant after the mixture of fertilizer and air, the electric signal of the change of the capacitance value is converted into voltage signal by the C-V converter (AD7746) and transmitted into the STM32F103 processor, the processor calculates the real-time fertilizer flow by filtering sampling.

[0032] When a new fertilizer is used, the fertilizer is poured into the sensor through the calibration hole, the corresponding capacitance value is recorded, the voltage-seeding amount relationship fitting is obtained by least square fitting according to n parts of voltage-fertilizer quality relationship data, the fertilization amount is calculated by using the voltage-seeding amount relationship fitting formula, the CAN bus sends the host computer, one host computer detects 8 fertilization pipes to adjust the fertilization amount, and is combined with the running speed to form a closed loop control circuit.

[0033] Compared with the prior art, the device can be used in the side deep fertilization technology of rice, which is used to position, quantify and uniformly apply the fertilizer to the soil under the rice seedling root side according to the agricultural requirements at one time while the rice is mechanically transplanted. Compared with the traditional throwing and scattering fertilization method, the side deep fertilization can effectively improve the fertilizer utilization rate, can monitor the rice side deep variable fertilization flow in real time, and can carry out closed loop control on the electric or air-assisted fertilizer distributor on this basis.

[0034] The above specific implementation can be adjusted in different ways by those skilled in the art without departing from the principles and purposes of the application, the protection scope of the application is subject to the claims and is not limited by the above specific implementation, and each implementation scheme within the scope is subject to the constraints of the application.

Claims

1. A capacitance type paddy rice side deep fertilization flow monitoring device, characterized by, The application relates to a capacitive fertilizer flow sensor, an information processing system arranged on two sides of the capacitive fertilizer flow sensor and a conduit joint with a calibration fertilizer injection port. The conduit joint is arranged outside the capacitive fertilizer flow sensor through a capacitive conduit gasket, the capacitive fertilizer flow sensor is connected with the information processing control system arranged in a circuit installation box, the fertilizer directly generates an electric signal when flowing into the conduit joint and the capacitive fertilizer flow sensor from the fertilizer injection port, the control system obtains calibration information of the fertilizer after processing the electric signal, and the fertilization amount is adjusted after judgment. The capacitive fertilizer flow sensor comprises a pair of symmetrically arranged circular arc-shaped capacitor plates, specifically two symmetrically arranged circular arc-shaped copper sheets with a radius of , a central angle of , a thickness of h and a length of L, which are fixedly arranged on a sensor shell, wherein ; The capacitance detection formula of the capacitive fertilizer flow sensor is Wherein, V is the space volume surrounded by the two symmetrical circular arc plates, V is the volume occupied by the fertilizer in V, V is the volume occupied by the air in V; εr is the relative dielectric constant of the fertilizer, ε0 is the relative dielectric constant of the air; θ is the central angle corresponding to the arc length of the circular arc plate. The calibration information of the fertilizer is specifically obtained in the following manner: G Wherein: G is the measured fertilizer quality, C is the measured capacitance, and a and b are fitting coefficients obtained by least square fitting. The adjustment of the fertilization amount comprises the following steps: Step 1, on-site real-time calibration measurement: a calibration fertilizer injection port is arranged on one side of a fertilizer inlet pipe on the upper side of the sensor, n portions of fertilizer with different types and typical water contents are taken in the range of the fertilization amount, the n portions of fertilizer are respectively injected in 5 seconds, the corresponding mass and the corresponding capacitance value are respectively recorded, and linear fitting is carried out according to the least square method; Step 2, a corresponding fitting formula of the flow mass and the capacitance of different fertilizer types and water contents is established on a vehicle-mounted upper monitoring interface, the fertilizer type and the water content are selected in actual application, and the upper computer program automatically matches and detects the fitting formula.

2. The capacitance type flow monitoring device for side deep fertilization of rice according to claim 1, wherein The control system is arranged in the circuit installation box and comprises a capacitive-voltage conversion circuit, an in-situ fertilization amount information processing circuit and an information output circuit.

3. The capacitance type flow monitoring device for side deep fertilization of rice according to claim 2, characterized in that, The noise reduction processing refers to: the in-situ processing circuit of the fertilization amount information samples and averages the content value to obtain a base signal , and the effective capacitance during subsequent fertilization flow is described as , wherein The real-time output value of the capacitance sensor is .

4. The capacitance type flow monitoring device for side deep fertilization of rice according to claim 2, characterized in that, The calibration process refers to the calibration of fertilizer types, temperature and humidity compensation, specifically: according to the normal unit time fertilization demand range, unit g / s, take n different fertilization requirements of fertilizer in a short time t, , respectively, through the range of n t time fertilization, respectively, through the calibration hole into the touch sensor, record the corresponding capacitance value, according to the n voltage-fertilizer quality relationship data, through the least square fitting to obtain the voltage-seeding amount relationship fitting, stored in the host computer monitoring system.

5. The capacitance type flow monitoring device for side deep fertilization of rice according to claim 2, characterized in that, The capacitive-voltage conversion circuit is connected with two electrodes of the capacitive fertilizer flow sensor, the capacitive electrode plate is excited and charged, the capacitive information is converted into a voltage signal and sent to the upper computer, the in-situ fertilization amount information processing circuit carries out denoising processing and calibration processing on the voltage signal, and the information output circuit uploads the calibration result to the upper computer to realize fertilization leakage alarm. The fertilization leakage alarm refers to that the calibration result of each flow monitoring device is compared with a threshold value, and the fertilization leakage alarm is carried out when the fertilization amount is lower than the threshold value.

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