Capacitive rice side deep fertilization flow monitoring device

Abstract

A capacitive rice side deep fertilization flow monitoring device comprises a capacitive fertilizer flow sensor, information processing systems arranged on the two sides of the capacitive fertilizer flow sensor respectively, and a guide pipe connector with a calibrated fertilizer feeding opening, and the guide pipe connector is arranged outside the capacitive fertilizer flow sensor through a capacitive guide pipe gasket. The capacitive fertilizer flow sensor is connected with an information processing control system arranged in the circuit installation box, the fertilizer flows into the guide pipe connector from the fertilizer feeding port and the capacitive fertilizer flow sensor directly generate electric signals, the control system processes the electric signals to obtain calibration information of the fertilizer, and the fertilizer application amount is adjusted through judgment. According to the invention, on-site real-time automatic calibration of a measurement fitting formula relation curve can be realized according to fertilizer types and different temperature and humidity, and the environmental adaptation and accuracy of fertilizer amount monitoring are greatly improved. The functions of fertilizer flow calibration, monitoring, fertilization leakage alarm and the like of rice side deep fertilization are achieved, and feedback data are provided for fertilization closed-loop control.

Description

Technical Field

[0001] The present invention relates to a technology in the field of agricultural automation, in particular to a capacitive rice side deep fertilization flow monitoring device. Background Art

[0002] Deep side variable fertilization of rice requires real-time monitoring of fertilizer flow, based on which closed-loop control of electric or pneumatic fertilizer dispensers is performed. However, the existing plane parallel plate capacitor fertilizer flow sensor has a small gap between the plates, which can easily cause fertilizer blockage; the arc plate fertilizer flow capacitor sensor can only detect blockage or empty pipes in fertilizer discharge pipes, but cannot achieve real-time quantitative detection and cannot meet the real-time monitoring requirements of fertilizer flow for precise variable fertilization. Summary of the Invention

[0003] This invention addresses the shortcomings of existing deep side fertilization technology for rice, which lacks an effective fertilizer flow monitoring device and makes it difficult to accurately control fertilizer application according to the fertilization prescription and operation speed. Instead, it proposes a symmetrical arc-plate capacitor-type flow monitoring device for deep side fertilization of rice. The device features a large fertilizer flow channel, effectively preventing fertilizer blockage. It also enables on-site, real-time automatic calibration of the measured fitting formula relationship curve based on fertilizer type and temperature and humidity, significantly improving the environmental adaptability and accuracy of fertilizer monitoring. This device implements fertilizer flow calibration, monitoring, and missed application alarms for deep side fertilization of rice, providing feedback data for closed-loop fertilization control.

[0004] The present invention is achieved through the following technical solutions:

[0005] The present invention 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 respectively arranged on both sides of the capacitive fertilizer flow sensor, and a conduit joint with a calibrated fertilizer feeding port. The conduit joint is arranged on the outside of the capacitive fertilizer flow sensor via a capacitive conduit gasket. The capacitive fertilizer flow sensor is connected to an information processing control system arranged in a circuit installation box. Fertilizer flows from the fertilizer feeding port into the conduit joint and the capacitive fertilizer flow sensor, directly generating an electrical signal. The control system processes the electrical signal to obtain fertilizer calibration information, and adjusts the fertilizer application amount based on the judgment.

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

[0007] The capacitance detection formula of the capacitive fertilizer flow sensor is: , where: V is the volume of space enclosed by two symmetrical arc plates, is the volume occupied by the fertilizer in V, is the volume occupied by air in V; is the relative dielectric constant of the fertilizer, is the relative dielectric constant of air; is the central angle corresponding to the arc length of the arc plate.

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

[0009] The described adjustment of fertilization amount comprises:

[0010] Step 1: On-site real-time calibration measurement: A calibration feeding port is opened on the fertilizer access pipe on the upper side of the sensor. Fertilizers of different types and typical moisture contents are fed in at different rates within the fertilizer discharge range for 5 seconds. The corresponding mass and capacitance integral are recorded, and linear fitting is performed using the least squares method.

[0011] Step 2: Establish the corresponding relationship between the flow mass and capacitance corresponding fitting formula for different fertilizer types and moisture contents on the vehicle-mounted upper monitoring interface. In actual application, select the fertilizer type and moisture content, and the upper computer program will automatically match and detect the fitting formula.

[0012] Technical Effects

[0013] The present invention can realize real-time quantitative detection of fertilizer flow quality, breaking the original monitoring and alarm of only blockage and empty discharge; at the same time, it has an adaptive correction selection algorithm for different fertilizer types and different moisture contents of fertilizer amounts, which can meet the real-time monitoring of fertilizer amounts in diverse outdoor environments of farmland, provide real-time precision detection for side deep fertilization of rice, and provide information guarantee for precise variable fertilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the present invention;

[0015] Figure 2 This is a schematic diagram of a capacitive fertilizer flow sensor;

[0016] Figure 3 for Figure 1 Explosion diagram;

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

[0018] Figure 5 It is a cross-sectional view of the present invention;

[0019] In the figure: catheter joint 1, fertilizer feeding port 2, catheter joint gasket 3, arc capacitor box 4, circuit installation box 5, capacitor catheter lower interface 6, arc capacitor plate 7, insulating nylon shell 8, capacitor connection circuit 9, side panel 10. DETAILED DESCRIPTION

[0020] like Figure 1-Figure 3 As shown, this embodiment relates to a capacitive rice side deep fertilization flow monitoring device, comprising: a capacitive fertilizer flow sensor, a circuit installation box 5 respectively arranged on both sides of the capacitive fertilizer flow sensor, and a conduit connector 1 with a calibrated fertilizer inlet 2, wherein: one end of the conduit connector 1 is connected to the upstream fertilizer discharge pipe via a corrugated tube, and the other end is arranged outside the capacitive fertilizer flow sensor via a capacitive conduit gasket 3. The capacitive fertilizer flow sensor is connected to a control system disposed in the circuit installation 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 fertilizer flow quality information, and adjusts the fertilizer amount based on the judgment.

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

[0022] The conduit joint 2 is provided with corrugations and is connected to the upstream fertilizer feeding pipe via the corrugations.

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

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

[0025] Because the relative dielectric constants of fertilizer and air are different, when fertilizer passes through the capacitive sensor, the dielectric constant between the capacitor plates will change, causing the output capacitance value to change due to the change in dielectric constant. The change in capacitance value is linearly related to the fertilizer flow mass within a certain range, and least squares geometry can be used to determine the instantaneous flow rate of fertilizer.

[0026] When the fertilizer passes through the arc capacitor plate, the dielectric constant of the sensor is , the capacitance of the plate is ,in: is the volume occupied by the fertilizer, is the volume occupied by air, V is the volume of space enclosed by two symmetrical arc plates, in mm3 , is the relative dielectric constant of the fertilizer, is the relative dielectric constant of air, is the half-open angle of the arc plate, is the central angle of the arc plate arc, and the instantaneous total amount of fertilizer flowing through is obtained by combining the empirical formula , a and b will vary with the type of fertilizer, ambient temperature and humidity. When the type of fertilizer and temperature and humidity change, recalibration and fitting are required.

[0027] like Figure 3 and Figure 4 As shown, the control system is arranged in the circuit installation box 5, including: a capacitance-voltage (CV) conversion circuit, an in-situ processing circuit for fertilizer application information, and an information output circuit, wherein: the capacitance-voltage (CV) conversion circuit is connected to the two electrodes of the capacitive fertilizer flow sensor, performs charge and discharge excitation and capacitance acquisition on the capacitor plates, and converts the capacitance information into a voltage signal and sends it to the host computer; the in-situ processing circuit for fertilizer application information performs noise reduction processing on the voltage signal and then calibrates it; the information output circuit uploads the calibration result to the host computer to realize a fertilizer omission alarm.

[0028] The noise reduction process is as follows: the fertilizer amount information in-situ processing circuit processes the time period when no fertilizer is flowing. The base signal is obtained by sampling and averaging the content value , the effective capacitance when the subsequent fertilizer flows through is described as ,in It is the real-time output value of the capacitive sensor.

[0029] The calibration process is to calibrate the fertilizer type, temperature and humidity compensation, specifically: according to the usual fertilizer application rate (g / s) requirement range, take n portions of fertilizers with different fertilizer application rates within a short time t ( ), take n portions of fertilizer application at t time within the range, respectively, and put them into the touch sensor through the calibration hole, record the corresponding capacitance value, and according to the n portions of voltage-fertilizer quality relationship data, obtain the voltage-seeding amount relationship fitting through least squares fitting, and store it in the upper computer monitoring system.

[0030] The fertilization missed alarm means that the calibration result of each flow monitoring device is compared with a threshold value, and a fertilization missed alarm is issued when the amount of fertilizer applied is lower than the threshold value.

[0031] This embodiment specifically works in the following manner: after fertilization begins, the operator starts the machine and selects the corresponding fertilizer type and moisture content on the host computer interface. The fertilizer flows into the capacitive fertilizer flow sensor with symmetrical arc-shaped plates of the present invention through the fertilizer inflow guide tube. The fertilizer flow introduced by the catheter connector 1 passes through the arc capacitor plate 7. The capacitance value changes due to the change in capacitance constant after the fertilizer and air are mixed. The electrical signal of the capacitance value change is converted into a voltage signal by the CV converter (AD7746) and transmitted to the STM32F103 processor. The processor calculates the real-time fertilizer flow through filtering and sampling.

[0032] When a new fertilizer is used, the fertilizer is put into the sensor through the calibration hole, and the corresponding capacitance value is recorded. Based on n sets of voltage-fertilizer mass relationship data, the voltage-seeding amount relationship fitting is obtained through least squares fitting. The fertilizer amount is calculated using the voltage-seeding amount relationship fitting formula, and the CAN bus is sent to the host computer. A host computer detects 8 fertilizer pipes and adjusts the fertilizer amount. At the same time, it is combined with the travel speed to form a closed-loop control circuit.

[0033] Compared with the existing technology, this device can apply deep fertilizer on the side of rice. The technology is to use the rice side deep fertilizer applicator to apply fertilizer in a one-time, quantitative and uniform manner in the soil below the root side of the rice seedlings according to agronomic requirements while the rice is mechanically transplanted. Compared with the traditional broadcast fertilization method, side deep fertilization can effectively improve the fertilizer utilization rate, and can monitor the variable side deep fertilizer flow of rice in real time, and on this basis, perform closed-loop control of the electric or air-blown fertilizer dispenser.

[0034] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principles and purpose of the present invention. The scope of protection of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. All implementation schemes within its scope shall be subject to the constraints of the present invention.

Claims

1. A capacitive rice side deep fertilization flow monitoring device, characterized in that: include: A capacitive fertilizer flow sensor, an information processing system and a conduit joint with a calibrated fertilizer feeding port are provided on both sides of the capacitive fertilizer flow sensor. The conduit joint is provided on the outside of the capacitive fertilizer flow sensor via a capacitive conduit gasket. The capacitive fertilizer flow sensor is connected to an information processing control system provided in a circuit installation box. Fertilizer flows from the fertilizer feeding port into the conduit joint and the capacitive fertilizer flow sensor, directly generating an electrical signal. The control system processes the electrical signal to obtain fertilizer calibration information and adjusts the fertilizer application amount based on the judgment.

2. The capacitive rice side deep fertilization flow monitoring device according to claim 1 is characterized in that: The capacitive fertilizer flow sensor comprises a pair of symmetrically arranged arc-shaped capacitor plates, specifically: a radius of R, a central angle of , two symmetrically arranged arc-shaped copper sheets with a thickness of h and a length of L, which are fixed on the sensor housing, wherein: R.

3. The capacitive rice side deep fertilization flow monitoring device according to claim 1 is characterized in that: The capacitance detection formula of the capacitive fertilizer flow sensor is: , where: V is the volume of space enclosed by two symmetrical arc plates, is the volume occupied by the fertilizer in V, is the volume occupied by air in V; is the relative dielectric constant of the fertilizer, is the relative dielectric constant of air; is the central angle corresponding to the arc length of the arc plate; The calibration information of the fertilizer is obtained specifically by the following method: , where: G is the measured fertilizer mass, C is the measured capacitance, a and b are fitting coefficients, obtained by least squares fitting.

4. The capacitive rice side deep fertilization flow monitoring device according to claim 1 is characterized in that: The described adjustment of fertilization amount comprises: Step 1: On-site real-time calibration measurement: A calibration feeding port is opened on the side of the fertilizer access pipe on the upper side of the sensor. Fertilizers of different types and typical moisture contents are taken within the fertilizer discharge range and n portions of fertilizer are added within 5 seconds. The corresponding mass and corresponding capacitance values ​​are recorded respectively, and linear fitting is performed according to the least squares method; Step 2: Establish the corresponding relationship between the flow mass and capacitance corresponding fitting formula for different fertilizer types and moisture contents on the vehicle-mounted upper monitoring interface. In actual application, select the fertilizer type and moisture content, and the upper computer program will automatically match and detect the fitting formula.

5. The capacitive rice side deep fertilization flow monitoring device according to claim 1 is characterized in that: The control system is arranged in a circuit installation box and includes: a capacitance-voltage (CV) conversion circuit, an in-situ processing circuit for fertilizer application amount information, and an information output circuit, wherein: the capacitance-voltage (CV) conversion circuit is connected to the two electrodes of the capacitive fertilizer flow sensor, performs charge and discharge excitation on the capacitor plates and capacitance acquisition, and converts the capacitance information into a voltage signal and sends it to a host computer; the in-situ processing circuit for fertilizer application amount information performs noise reduction processing on the voltage signal and then performs calibration processing; the information output circuit uploads the calibration result to the host computer to realize a fertilizer omission alarm.

6. The capacitive rice side deep fertilization flow monitoring device according to claim 5, characterized in that: The noise reduction process is as follows: the fertilizer amount information in-situ processing circuit processes the time period when no fertilizer is flowing. The base signal is obtained by sampling and averaging the content value , the effective capacitance when the subsequent fertilizer flows through is described as ,in It is the real-time output value of the capacitive sensor.

7. The capacitive rice side deep fertilization flow monitoring device according to claim 5, characterized in that: The calibration process is to calibrate the fertilizer type, temperature and humidity compensation, specifically: according to the usual fertilizer application rate (g / s) requirement range, take n portions of fertilizers with different fertilizer application rates within a short time t ( ), take n portions of fertilizer application at t time within the range, respectively, and put them into the touch sensor through the calibration hole, record the corresponding capacitance value, and according to the n portions of voltage-fertilizer quality relationship data, obtain the voltage-seeding amount relationship fitting through least squares fitting, and store it in the upper computer monitoring system.

8. The capacitive rice side deep fertilization flow monitoring device according to claim 5, characterized in that: The fertilization missed alarm means that the calibration result of each flow monitoring device is compared with a threshold value, and a fertilization missed alarm is issued when the amount of fertilizer applied is lower than the threshold value.

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