Fogdrop deposition sensor and detection method

Abstract

The invention discloses a fogdrop deposition sensor which comprises a base, an upper polar plate, a lower polar plate, a horizontal movement device, a stepping motor, a controller, a first supporting frame, a second supporting frame and a fogdrop shielding plate. The upper polar plate is fixedly connected with the horizontal movement device; the first support frame and the second support frame are fixed on the base; the sensor disclosed by the invention has the advantages of good linear relationship between the output voltage variation and the fog drop deposition amount and small measurement error.

Description

Technical Field

[0001] The present invention relates to a droplet deposition sensor and a detection method, belonging to the technical field of agricultural facilities. Background Art

[0002] The greenhouse planting area in China has been increasing year by year and currently accounts for 85% of the total global greenhouse area. However, compared with developed countries such as the Netherlands, Japan, and the United States, greenhouse operations in China mainly rely on manual labor and have a low level of mechanical automation. Due to the high planting density in greenhouses, combined with high internal temperature, high humidity, and poor ventilation in the enclosed space, pests and diseases are more likely to occur. Chemical pesticides are still one of the main means for controlling pests and diseases in greenhouses. Precise pesticide application technology can greatly improve the utilization rate of pesticides, reduce pesticide residues, and minimize environmental pollution. Rapid and effective acquisition of droplet deposition distribution can reduce the experimental costs, lower the experimental complexity, and improve the experimental efficiency in the research of precise pesticide application technology. Figure 1 The figure shows the schematic diagram of an existing capacitive droplet deposition detection sensor. There are many electrodes distributed on an insulating substrate, and all the electrodes are connected in parallel; the distance between adjacent electrodes and the height of the electrodes should be approximately the same as the size of the droplets, so as to ensure a good linear relationship between the change in the output voltage of the capacitive sensor and the droplet deposition amount. To ensure a good linear relationship, the existing capacitive droplet deposition sensor must have a very small electrode spacing, otherwise the droplets cannot fill the space between the electrodes (as shown in Figure 2 ), and at the same time, the electrode height cannot be too high, otherwise the droplets are likely to hang on the surface of the electrodes before reaching the bottom of the electrodes. To ensure a small electrode spacing and a small electrode height means that there are many electrodes densely distributed on the insulating substrate. This will bring the following problems: many droplets land on the ends of the electrodes rather than between adjacent electrodes, and some droplets land between adjacent electrodes but exceed the height of the electrodes (as shown in Figure 3 ), which will lead to large measurement errors. At the same time, implementing the above design requires high manufacturing processes. Summary of the Invention

[0003] The objective of the present invention is to design a new structure of a droplet deposition sensor and a detection method.

[0004] To solve the above technical problems, the technical solution adopted by the present invention is:

[0005] A droplet deposition sensor, comprising a base, an upper plate, a lower plate, a horizontal movement device, a motor, a controller, a first support frame, a second support frame and a droplet baffle; the upper plate is fixedly connected to the horizontal movement device; a hydrophobic substance is coated on the upper surface of the lower plate, and the friction coefficient of the upper surface of this substance is greater than that of the plate surface; the droplet baffle is located above the lower plate, and through holes are provided on the droplet baffle; the area of the through holes is slightly smaller than the area of the lower plate; the upper plate is located between the droplet baffle and the lower plate; the first support frame and the second support frame are fixed to the base; the lower plate is fixed to the first support frame; the droplet baffle is fixed to the second support frame; the droplet baffle ensures that the droplets fall on the lower plate after passing through the through holes, and since the area of the through holes is slightly smaller than the area of the lower plate, there will be no droplets at the four peripheral edges of the lower plate; the controller drives the horizontal movement device to move horizontally through the motor, thereby driving the upper plate to move horizontally; the distance between the upper plate and the lower plate satisfies 0.1y ≤ d ≤ 0.8y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet.

[0006] A more preferred technical solution further comprises a vertical movement device; the upper plate is driven by another motor to move in the vertical direction.

[0007] A droplet deposition sensor, comprising a base, an upper plate, a lower plate, a horizontal movement device, a motor, a controller, a first support frame, a second support frame and a droplet baffle; the lower plate is fixed to the horizontal movement device; a hydrophobic substance is coated on the upper surface of the lower plate, and the friction coefficient of the upper surface of this substance is greater than that of the plate surface; the droplet baffle is located above the lower plate, and through holes are provided on the droplet baffle, and the area of the through holes is slightly smaller than the area of the lower plate; the upper plate is located between the droplet baffle and the lower plate; the first support frame and the second support frame are fixed to the base; the upper plate is fixed to the first support frame; the droplet baffle is fixed to the second support frame; the droplet baffle ensures that the droplets fall on the lower plate after passing through the through holes, and since the area of the through holes is slightly smaller than the area of the lower plate, there will be no droplets at the four peripheral edges of the lower plate; the controller drives the horizontal movement device to move horizontally through the motor, thereby driving the lower plate to move horizontally to the lower part of the through holes of the droplet baffle; the distance between the upper plate and the lower plate satisfies 0.1y ≤ d ≤ 0.8y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet.

[0008] A more preferred technical solution is that the lower plate is also connected to the vertical movement device, and is driven by another motor to move in the vertical direction.

[0009] When it is necessary to collect droplets, the controller first drives the vertical motion device to move vertically through the second stepper motor, thereby driving the lower plate to move downward in the vertical direction. Then, it drives the horizontal motion device to move horizontally through the first stepper motor, thereby driving the lower plate to move horizontally to the position below the through-hole of the droplet baffle. When the lower plate needs to be reset after collecting the droplets, the controller first drives the horizontal motion device to move horizontally through the first stepper motor, thereby driving the lower plate to move leftward in the horizontal direction. Then, it drives the vertical motion device to move vertically through the second stepper motor, thereby driving the lower plate to move upward in the vertical direction.

[0010] Among them, the horizontal motion device is realized by a ball screw. The vertical motion device is realized by a ball screw. The motor uses a stepper motor. The hydrophobic substance uses frosted PVC with a thickness of 0.15 mm.

[0011] A method for detecting a droplet deposition sensor, the sensor includes a base, an upper plate, a lower plate, a horizontal motion device, a vertical motion device, a first stepper motor, a second stepper motor, a controller, a first support frame, a second support frame, and a droplet baffle;

[0012] The upper plate is fixedly connected to the horizontal motion device and is also connected to the vertical motion device;

[0013] The upper surface of the lower plate is covered with a hydrophobic substance, and the friction coefficient of the upper surface of this substance is greater than that of the plate surface. The droplet baffle is located above the lower plate, and through-holes are provided on the droplet baffle. The area of the through-hole is slightly smaller than the area of the lower plate. The upper plate is located between the droplet baffle and the lower plate. The first support frame and the second support frame are fixed to the base. The lower plate is fixed to the first support frame. The droplet baffle is fixed to the second support frame;

[0014] The droplet baffle ensures that the droplets fall on the lower plate after passing through the through-hole. Since the area of the through-hole is slightly smaller than the area of the lower plate, there will be no droplets at the four peripheral edges of the lower plate;

[0015] The distance between the upper plate and the lower plate satisfies 0.1y ≤ d ≤ 0.8y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet;

[0016] When it is necessary to collect droplets, the controller first drives the vertical motion device to move vertically through the second stepping motor, thereby driving the upper plate to move upward in the vertical direction, and then drives the horizontal motion device to move horizontally through the first stepping motor, thereby driving the upper plate to move horizontally; when the upper plate needs to be reset after collecting the droplets, the controller first drives the horizontal motion device to move horizontally through the first stepping motor, thereby driving the upper plate to move horizontally to the right, and then drives the vertical motion device to move vertically through the second stepping motor, thereby driving the upper plate to move downward in the vertical direction.

[0017] A method for detecting a droplet deposition sensor, comprising a base, an upper plate, a lower plate, a horizontal motion device, a vertical motion device, a first stepping motor, a second stepping motor, a controller, a first support frame, a second support frame and a droplet baffle; the lower plate is connected to the horizontal motion device and is also connected to the vertical motion device; a hydrophobic substance is coated on the upper surface of the lower plate, and the friction coefficient of the upper surface of this substance is greater than the friction coefficient of the plate surface; the droplet baffle is located above the lower plate, and through holes are provided on the droplet baffle, and the area of the through holes is slightly smaller than the area of the lower plate; the upper plate is located between the droplet baffle and the lower plate; the first support frame and the second support frame are fixed on the base; the upper plate is fixed on the first support frame; the droplet baffle is fixed on the second support frame;

[0018] The distance between the upper plate and the lower plate satisfies 0.1y ≤ d ≤ 0.8y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet;

[0019] When it is necessary to collect droplets, the controller first drives the vertical motion device to move vertically through the second stepping motor, thereby driving the lower plate to move downward in the vertical direction, and then drives the horizontal motion device to move horizontally through the first stepping motor, thereby driving the lower plate to move horizontally to below the through hole of the droplet baffle; when the lower plate needs to be reset after collecting the droplets, the controller first drives the horizontal motion device to move horizontally through the first stepping motor, thereby driving the lower plate to move horizontally to the left, and then drives the vertical motion device to move vertically through the second stepping motor, thereby driving the lower plate to move upward in the vertical direction;

[0020] Algorithm analysis:

[0021] When no droplets are collected on the lower plate, only air exists between the upper plate and the lower plate, and the capacitance of the capacitor is In the formula, ε0 is the air dielectric constant; S0 is the area of the lower plate;

[0022] After the lower electrode plate has collected the reset of the droplets, the medium between the upper electrode plate and the lower electrode plate is composed of a mixture of air and droplets; since the droplets are compressed, the mixed medium is divided into two parts for independent consideration at this time; let the electrode plate area corresponding to the droplets be S1, then the electrode plate area corresponding to the air is S0 - S1; at this time, the capacitance of the capacitor is

[0023] In the formula, ε x is the dielectric constant of the droplets,

[0024] Then It can be obtained from formula (1) that the mass of the droplets detected at this time

[0025]

[0026] In the formula, ρ is the density of the spraying droplets; during the same spraying process, ε x and ρ are constants. According to formula (2), it can be known that the deposition amount of the droplets on the electrode plate is proportional to the change in capacitance. Therefore, theoretically, the deposition amount of the droplets can be measured by the change in capacitance.

[0027] When the droplet sizes between the upper electrode plate and the lower electrode plate are not the same, the selection of the electrode plate spacing refers to the size of the small droplets. Among them, the controller uses an STM32G031 single-chip microcomputer.

[0028] After each calculation of droplet collection is completed and the upper electrode plate and the lower electrode plate are shifted, use absorbent paper to wipe the upper surface of the lower electrode plate.

[0029] Compared with the existing technology, the advantages of the present invention are as follows: The present invention proposes a completely new variable medium capacitance sensor structure, no longer adopting the design concept of densely arranged electrode plates. For the existing capacitive droplet deposition sensor, to ensure a good linear relationship, it is necessary to ensure a very small electrode plate spacing, so that the deposited droplets fill the space between the electrode plates. At the same time, the height of the electrode plate cannot be too high, otherwise the droplets are likely to hang on the surface of the electrode plate before falling to the bottom of the electrode plate. To ensure a small electrode plate spacing and a small electrode plate height means that there are many electrode plates densely distributed on the insulating substrate. This will bring the following problems: Many droplets fall on the ends of the electrode plates, rather than between adjacent electrode plates, and there are also droplets that fall between adjacent electrode plates but exceed the height of the electrode plates. These problems will lead to large measurement errors. The most difficult thing is that the manufacturing process requirements are very high. The present invention uses two movable large electrode plates. When it is necessary to collect droplets, the controller controls the horizontal movement device to drive the upper electrode plate or the lower electrode plate to move, so that the droplets directly fall on the lower electrode plate, which can ensure that all the droplets falling on the lower electrode plate can be measured.

[0030] Since the distance between the upper plate and the lower plate is smaller than the diameter of the fog droplets, the fog droplets located between the plates are compressed. Due to the fluid properties of the fog droplets, the fog droplets start to flow slowly when compressed, causing the reading of the sensor to increase slowly and stop after about 30 minutes. To solve this problem, the inventor began to increase the distance, so that the fog droplets are compressed less. After repeated experiments, the sensor reading still increased slowly. Later, the inventor thought of covering the lower plate with a material with a large coefficient of friction. However, a large number of experiments found that the compressed fog droplets still flowed slowly and the sensor still could not read normally. After repeated experiments, the inventor accidentally discovered that if the material covered on the lower plate is a hydrophobic material with a large surface friction coefficient, the fog droplets will not flow slowly when compressed between the upper and lower plates, and the sensor reading is stable. When using a PVC material with a matte surface and adjusting the distance between the upper and lower plates vertically, it was surprisingly found that the compressed fog droplets almost instantaneously stabilized, and the sensor reading also almost instantaneously stabilized.

[0031] This invention requires that the distance between the upper plate and the lower plate is smaller than the particle size of the fog droplets. According to the inherent thinking, it would be thought that during the horizontal movement and reset process of the lower plate after collecting the fog droplets, the fog droplets on the lower plate would slide off when contacting the upper plate. In fact, the fog droplets will not slide off the lower plate (skillfully utilizing the liquid interface tension). In order to accurately calculate the mass of the fog droplets on the lower plate, this invention needs to ensure that the distance between the upper and lower plates and the particle size of the fog droplets satisfy a certain relationship: 0.1y ≤ d ≤ 0.8y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the fog droplets. When this relational expression is satisfied, it can be ensured that the fog droplet medium and the air medium are in a parallel relationship; when the plate distance is greater than 0.8y, there will be many cases where the fog droplet medium and the air medium are in a series relationship; according to the capacitance series-parallel formula, when the fog droplet medium and the air medium are in series, the air dielectric constant is very small, which will lead to a very poor linear relationship of the sensor, complex data calculation, and also complex sensor calibration.

[0032] When the plate distance is less than 0.8y, the fog droplet medium and the air medium are almost all in a parallel relationship; when the plate distance is less than 0.1y, although the fog droplet medium and the air medium are both in a parallel relationship, since the fog droplets located between the upper plate and the lower plate are compressed too much, resulting in too large a deformation of a single fog droplet, and the fluid properties of the fog droplets determine that the compressed fog droplets keep flowing slowly. At this time, to stabilize the compressed fog droplets, higher requirements are put forward for the friction characteristics and hydrophobic characteristics of the material covered on the lower plate.

[0033] This structural design not only ensures a good linear relationship between the change in the output voltage of the sensor and the fog droplet deposition amount (simple calibration during the use of the sensor), but also can accurately measure the mass of all collected fog droplets with very small errors. Description of the Drawings

[0034] Figure 1It is a schematic structural diagram of a prior art droplet deposition sensor;

[0035] Figure 2 It is a schematic diagram showing that in the prior art, the droplets are too small to fill the adjacent electrode plates;

[0036] Figure 3 It is a schematic diagram showing that in the prior art, the droplets are too large and exceed the height of the electrode plates;

[0037] Figure 4 It is a schematic diagram of the present invention when the droplet between the electrode plates is compressed and deformed less;

[0038] Figure 5 It is a schematic diagram of the present invention when the droplet between the electrode plates is compressed and deformed more;

[0039] Figure 6 It is a schematic structural diagram of the first embodiment of the droplet deposition sensor of the present invention;

[0040] Figure 7 It is a schematic structural diagram of the second embodiment of the droplet deposition sensor of the present invention;

[0041] Figure 8 It is a schematic structural diagram of the third embodiment of the droplet deposition sensor of the present invention;

[0042] Figure 9 It is a schematic structural diagram of the fourth embodiment of the droplet deposition sensor of the present invention.

[0043] Among them, 11 is an insulating substrate; 12 is an electrode plate. 21 is a base; 22 is a horizontal movement device; 23 is an upper electrode plate; 24 is a lower electrode plate; 25 is a droplet baffle; 26 is a first support frame; 27 is a second support frame; 28 is a vertical movement device. Detailed implementation manners

[0044] The present invention will be further described in detail below with reference to the accompanying drawings.

[0045] Figure 2 And Figure 3 It shows the situations in the prior art where the droplets are too small to fill the electrode plates and the droplets are too large and exceed the height of the electrode plates. Figure 4 It shows that when the droplet is compressed and deformed very little, from top to bottom between the two vertical dotted lines in the figure are air, droplet, air, which means that air, droplet, air are in series relationship, and in this case, the linear relationship between the droplet deposition amount and the capacitance change amount is poor. Figure 5 It shows that when the droplet of the present invention is compressed and deformed greatly, the droplet and air are in parallel relationship, and in this case, the linear relationship between the droplet deposition amount and the capacitance change amount is good.

[0046] Embodiment 1: A droplet deposition sensor includes a base, an upper plate, a lower plate, a horizontal movement device (ball screw), a stepper motor, a controller, a first support frame, a second support frame, and a droplet baffle; the upper plate is fixedly connected to the horizontal movement device; the first support frame and the second support frame are fixed to the base; the lower plate is fixed to the first support frame; the droplet baffle is fixed to the second support frame; the upper surface of the lower plate is covered with frosted PVC with a thickness of 0.15 mm. The droplet baffle is located above the lower plate, and through holes are provided on the droplet baffle. The area of the through holes is slightly smaller than the area of the lower plate; the upper plate is located between the droplet baffle and the lower plate. The droplet baffle ensures that the droplets fall on the lower plate after passing through the through holes. Since the area of the through holes is slightly smaller than the area of the lower plate, there will be no droplets at the four peripheral edges of the lower plate. The controller drives the ball screw to move horizontally through the stepper motor, thereby driving the upper plate to move horizontally.

[0047] The distance between the upper plate and the lower plate is less than the diameter of the droplets. The distance between the upper plate and the lower plate satisfies 0.3y ≤ d ≤ 0.6y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplets. Preferably, d = 0.6y.

[0048] Table 1 shows the reading stability of the sensor after various materials are covered on the lower plate

[0049]

[0050] Embodiment 2: A droplet deposition sensor, comprising a base, an upper plate, a lower plate, a horizontal motion device (ball screw), a vertical motion device (ball screw), a stepper motor, a controller, a first support frame, a second support frame, and a droplet baffle; the first support frame and the second support frame are fixed to the base; the upper surface of the lower plate is covered with frosted PVC with a thickness of 0.15 mm. The lower plate is fixed to the first support frame; the droplet baffle is fixed to the second support frame; the droplet baffle is located above the lower plate, and through holes are provided on the droplet baffle. The area of the through holes is slightly smaller than the area of the lower plate; the upper plate is located between the droplet baffle and the lower plate. The droplet baffle ensures that the droplets fall on the lower plate after passing through the through holes. Since the area of the through holes is slightly smaller than the area of the lower plate, there will be no droplets at the four peripheral edges of the lower plate. The distance between the upper plate and the lower plate is preferably d = 0.5y. When droplets need to be collected, the controller first drives the vertical motion device (ball screw) to move vertically through the second stepper motor, thereby driving the upper plate to move upward in the vertical direction, and then drives the horizontal motion device (ball screw) to move horizontally through the first stepper motor, thereby driving the upper plate to move horizontally. When the upper plate needs to be reset after collecting the droplets, the controller first drives the horizontal motion device (ball screw) to move horizontally through the first stepper motor, thereby driving the upper plate to move horizontally to the right, and then drives the vertical motion device (ball screw) to move vertically through the second stepper motor, thereby driving the upper plate to move downward in the vertical direction. The advantage of controlling the movement of the upper plate in two-dimensional directions is that the droplet shape change is small and the sensor reading is more stable. The horizontal motion device and the vertical motion device respectively adopt separate ball screws.

[0051] Embodiment 3: A droplet deposition sensor, comprising a base, an upper plate, a lower plate, a horizontal motion device (ball screw), a stepper motor, a controller, a first support frame, a second support frame, and a droplet baffle; the lower plate is fixed to the horizontal motion device; the first support frame and the second support frame are fixed to the base; the upper plate is fixed to the first support frame; the droplet baffle is fixed to the second support frame; the upper surface of the lower plate is covered with frosted PVC with a thickness of 0.15 mm. The droplet baffle is located above the lower plate, through holes are provided on the droplet baffle, and the area of the through holes is slightly smaller than the area of the lower plate; the upper plate is located between the droplet baffle and the lower plate. The droplet baffle ensures that the droplets fall on the lower plate after passing through the through holes. Since the area of the through holes is slightly smaller than the area of the lower plate, there will be no droplets at the four peripheral edges of the lower plate. The controller drives the horizontal motion device (ball screw) to move horizontally through the stepper motor, thereby driving the lower plate to move horizontally. The distance between the upper plate and the lower plate is smaller than the diameter of the droplet. The distance between the upper plate and the lower plate satisfies 0.3y ≤ d ≤ 0.6y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet. Preferably, d = 0.5y.

[0052] Embodiment 4:

[0053] A droplet deposition sensor includes a base, an upper plate, a lower plate, a horizontal movement device (ball screw), a vertical movement device, a stepper motor, a controller, a first support frame, a second support frame, and a droplet baffle; the first support frame and the second support frame are fixed to the base; the upper plate is fixed to the first support frame; the droplet baffle is fixed to the second support frame; the upper surface of the lower plate is covered with frosted PVC with a thickness of 0.15 mm. The droplet baffle is located above the lower plate, and through holes are provided on the droplet baffle, and the area of the through holes is slightly smaller than the area of the lower plate; the upper plate is located between the droplet baffle and the lower plate. The droplet baffle ensures that the droplets fall on the lower plate after passing through the through holes. Since the area of the through holes is slightly smaller than the area of the lower plate, there will be no droplets at the four peripheral edges of the lower plate.

[0054] When it is necessary to collect droplets, the controller first drives the vertical movement device (ball screw) to move vertically through the second stepper motor, thereby driving the lower plate to move downward in the vertical direction, and then drives the horizontal movement device (ball screw) to move horizontally through the first stepper motor, thereby driving the lower plate to move horizontally. When the lower plate needs to be reset after collecting droplets, the controller first drives the horizontal movement device (ball screw) to move horizontally through the first stepper motor, thereby driving the lower plate to move leftward in the horizontal direction, and then drives the vertical movement device (ball screw) to move vertically through the second stepper motor, thereby driving the lower plate to move in the vertical direction. The advantage of controlling the movement of the lower plate in two-dimensional directions is that the droplet shape is smaller and the sensor reading is more stable. The horizontal movement device and the vertical movement device respectively adopt separate ball screws.

[0055] d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet. Preferably, d = 0.3y.

[0056] In the specification, a large number of specific details are disclosed. However, it should be understood that the embodiments of the disclosed content of the present invention can be practiced without these specific details. In some embodiments, the well-known methods, structures, and technologies are not shown in detail. The inventor believes that the public can understand these unpublished prior arts. Although the specification has shown and described the exemplary embodiments of the present invention, it is easy for those skilled in the art to understand that such embodiments are provided only by way of example. Those skilled in the art can think of many changes, alterations, and substitutions without departing from the present invention. It should be understood that various alternative solutions to the embodiments of the present invention described in the specification can be adopted in the practice of the present invention. The scope of the claimed rights of the present invention is subject to the content recorded in the claims.

Claims

1. A droplet deposition sensor, characterized in that, It includes a base, an upper plate, a lower plate, a horizontal movement device, a motor, a controller, a first support frame, a second support frame, and a droplet baffle; The upper plate is fixedly connected to the horizontal movement device; The upper surface of the lower plate is covered with a hydrophobic substance, and the friction coefficient of the upper surface of this substance is greater than that of the plate surface; The droplet baffle is located above the lower plate, and through holes are provided on the droplet baffle; The area of the through hole is slightly smaller than the area of the lower plate; The upper plate is located between the droplet baffle and the lower plate; The first support frame and the second support frame are fixed to the base; The lower plate is fixed to the first support frame; The droplet baffle is fixed to the second support frame; The droplet baffle ensures that the droplets fall on the lower plate after passing through the through hole. Since the area of the through hole is slightly smaller than the area of the lower plate, there will be no droplets at the four peripheral edges of the lower plate; The controller drives the horizontal movement device to move horizontally through the motor, thereby driving the upper plate to move horizontally; The distance between the upper plate and the lower plate satisfies 0.1y ≤ d ≤ 0.8y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet.

2. The droplet deposition sensor according to claim 1, characterized in that, It also includes a vertical movement device; The upper plate is also connected to the vertical movement device.

3. A droplet deposition sensor, characterized in that, It includes a base, an upper plate, a lower plate, a horizontal movement device, a motor, a controller, a first support frame, a second support frame, and a droplet baffle; The lower plate is fixed to the horizontal movement device; The upper surface of the lower plate is covered with a hydrophobic substance, and the friction coefficient of the upper surface of this substance is greater than that of the plate surface; The droplet baffle is located above the lower plate, and through holes are provided on the droplet baffle, and the area of the through hole is slightly smaller than the area of the lower plate; The upper plate is located between the droplet baffle and the lower plate; The first support frame and the second support frame are fixed to the base; The upper plate is fixed to the first support frame; The droplet baffle is fixed to the second support frame; The controller drives the horizontal movement device to move horizontally through the motor, so as to drive the lower plate to move horizontally to the lower part of the through hole of the droplet baffle; The distance between the upper plate and the lower plate satisfies 0.1y ≤ d ≤ 0.8y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet.

4. The droplet deposition sensor according to claim 3, wherein, It also includes a vertical movement device; The lower plate is also connected to the vertical movement device.

5. The droplet deposition sensor according to any one of claims 1-4, characterized in that The horizontal movement device is realized by a ball screw.

6. The droplet deposition sensor according to any one of claims 1-4, characterized in that The vertical movement device is realized by a ball screw.

7. The droplet deposition sensor according to any one of claims 1-4, characterized in that, The motor uses a stepper motor.

8. The droplet deposition sensor according to any one of claims 1-4, characterized in that, The hydrophobic substance uses frosted PVC with a thickness of 0.15 mm.

9. A method for detecting a droplet deposition sensor, characterized in that, The sensor includes a base, an upper plate, a lower plate, a horizontal movement device, a vertical movement device, a first stepper motor, a second stepper motor, a controller, a first support frame, a second support frame, and a droplet baffle; The upper plate is fixedly connected to the horizontal movement device and is connected to the vertical movement device; The upper surface of the lower plate is covered with a hydrophobic substance, and the friction coefficient of the upper surface of this substance is greater than that of the plate surface; The droplet baffle is located above the lower plate, and through holes are provided on the droplet baffle; The area of the through-hole is slightly smaller than the area of the lower plate; the upper plate is located between the droplet baffle and the lower plate; the first support frame and the second support frame are fixed to the base; the lower plate is fixed to the first support frame; the droplet baffle is fixed to the second support frame; The droplet baffle ensures that the droplets fall on the lower plate after passing through the through-hole. Since the area of the through-hole is slightly smaller than the area of the lower plate, there will be no droplets at the four peripheral edges of the lower plate; The distance between the upper plate and the lower plate satisfies 0.1y ≤ d ≤ 0.8y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet; When droplets need to be collected, the controller first drives the vertical movement device to move vertically through the second stepper motor, thereby driving the upper plate to move upward in the vertical direction, and then drives the horizontal movement device to move horizontally through the first stepper motor, thereby driving the upper plate to move horizontally; when the upper plate needs to be reset after collecting the droplets, the controller first drives the horizontal movement device to move horizontally through the first stepper motor, thereby driving the upper plate to move horizontally to the right, and then drives the vertical movement device to move vertically through the second stepper motor, thereby driving the upper plate to move downward in the vertical direction. When no droplets are collected by the lower electrode plate, only air exists between the upper and lower electrode plates, and the capacitance of the capacitor is where ε0 is the dielectric constant of air; S0 is the area of the lower electrode plate; After the lower electrode plate collects the reset of the droplets, the medium between the upper electrode plate and the lower electrode plate is composed of a mixture of air and droplets; since the droplets are compressed, the mixed medium is divided into two parts for independent consideration at this time; assuming that the plate area corresponding to the droplets is S1, the plate area corresponding to the air is S0 - S1; the capacitance of the capacitor at this time is where ε x is the dielectric constant of the droplet, Then It can be obtained from Equation (1) that the mass of the detected fog droplet at this time where ρ is the density of the applied pesticide droplets; since ε x and ρ are constants during the same pesticide application process, according to Equation (2), it can be seen that the deposition amount of droplets on the plate is proportional to the change in capacitance. Therefore, theoretically, the deposition amount of droplets can be measured by the change in capacitance.

10. A method for detecting a droplet deposition sensor, characterized in that It includes a base, an upper plate, a lower plate, a horizontal movement device, a vertical movement device, a first stepper motor, a second stepper motor, a controller, a first support frame, a second support frame and a droplet baffle; the lower plate is connected to the horizontal movement device and is also connected to the vertical movement device; a hydrophobic substance is coated on the upper surface of the lower plate, and the friction coefficient of the upper surface of this substance is greater than the friction coefficient of the plate surface; the droplet baffle is located above the lower plate, and through-holes are provided on the droplet baffle, and the area of the through-holes is slightly smaller than the area of the lower plate; the upper plate is located between the droplet baffle and the lower plate; the first support frame and the second support frame are fixed to the base; the upper plate is fixed to the first support frame; the droplet baffle is fixed to the second support frame; The distance between the upper plate and the lower plate satisfies 0.1y ≤ d ≤ 0.8y, where d is the distance between the upper plate and the lower plate, and y is the diameter of the droplet; When droplets need to be collected, the controller first drives the vertical movement device to move vertically through the second stepper motor, thereby driving the lower plate to move downward in the vertical direction, and then drives the horizontal movement device to move horizontally through the first stepper motor, thereby driving the lower plate to move horizontally to below the through-hole of the droplet baffle; when the lower plate needs to be reset after collecting the droplets, the controller first drives the horizontal movement device to move horizontally through the first stepper motor, thereby driving the lower plate to move horizontally to the left, and then drives the vertical movement device to move vertically through the second stepper motor, thereby driving the lower plate to move upward in the vertical direction; When no droplets are collected by the lower electrode plate, only air exists between the upper electrode plate and the lower electrode plate, and the capacitance of the capacitor is where ε0 is the dielectric constant of air; S0 is the area of the lower electrode plate; After the lower plate collects the reset droplets, the dielectric between the upper plate and the lower plate is composed of a mixture of air and droplets; since the droplets are compressed, the mixed dielectric is considered separately in two parts at this time; let the plate area corresponding to the droplets be S1, then the plate area corresponding to the air is S0 - S1; the capacitance of the capacitor at this time is where ε x is the dielectric constant of the droplet, Then From Equation (1), the mass of the detected droplets at this time where ρ is the density of the sprayed droplets; during the same spraying process, since ε x , ρ are constants, according to Equation (2), it can be known that the deposition amount of droplets on the plate is proportional to the change in capacitance. Therefore, theoretically, the deposition amount of droplets can be measured by the change in capacitance.

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