Handheld device for automatically measuring plant electrophysiological indexes

Abstract

A handheld device for automatically measuring plant electrophysiological indexes comprises an upper pole plate chuck and a lower pole plate chuck which are oppositely arranged on a support, the upper pole plate chuck is arranged on the support through an electric push rod and a universal joint, a pressure sensing mechanism is arranged in the lower pole plate chuck, the pressure sensing mechanism and the electric push rod are connected with a single-chip microcomputer, and the single-chip microcomputer is connected with a power source. When the upper chuck is in contact with the lower chuck, the centers of the upper chuck and the lower chuck are overlapped in the vertical direction, a leaf to be tested is clamped between the upper chuck and the lower chuck, and an electrophysiological signal of the leaf is collected through an LCR tester. According to the invention, the electrophysiological signal data of the plant leaf under the specific clamping force can be automatically and accurately measured.

Description

Technical Field

[0001] The invention relates to a technology in the field of agricultural engineering, in particular to a handheld device for automatically measuring electrophysiological indicators of plants under a specific clamping force. Background Art

[0002] The existing LCR tester can measure the electrophysiological indicators of plant leaves, such as physiological resistance, physiological capacitance, and physiological impedance. The cell sap solute in the leaf is used as the dielectric, and the leaf is clamped between two parallel electrode plates of a parallel plate capacitor to form a parallel plate capacitance sensor. Applying different clamping forces (pressures) to the two parallel electrode plates will lead to different changes in the concentration of cell sap solutes in the leaf, thereby changing the elasticity and plasticity of the leaf cells, causing changes in the dielectric constant of the cell sap solutes in the leaf tissue between the two parallel electrode plates, and affecting the electrophysiological information of the plant. By changing the clamping force, different electrophysiological signals of plant leaves can be obtained, and these data are helpful in studying the physiological condition of plants. Summary of the invention

[0003] In view of the disadvantage that the prior art has low control precision of leaf pressure, resulting in poor measurement accuracy, the present invention proposes a handheld device for automatically measuring plant electrophysiological indicators, which can automatically and accurately measure the electrophysiological signal data of plant leaves under a specific clamping force.

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

[0005] The present invention relates to a handheld device for automatically measuring plant electrophysiological indicators, comprising: an upper pole plate chuck and a lower pole plate chuck which are relatively arranged on a bracket, wherein: the upper pole plate chuck is arranged on the bracket through an electric push rod and a universal joint, a pressure sensing mechanism is arranged in the lower pole plate chuck, the pressure sensing mechanism and the electric push rod are respectively connected to a single-chip computer, the upper chuck overlaps with the lower chuck in the vertical direction when in contact with the lower chuck, a leaf to be measured is clamped between the upper chuck and the lower chuck, and an electrophysiological signal of the leaf is collected through an LCR tester.

[0006] The single chip microcomputer comprises: a pressure monitoring unit, a comparison control unit, an execution control unit and a communication unit, wherein: the pressure monitoring unit monitors and obtains the pressure value F1 corresponding to the current clamping force in real time by connecting to a pressure sensor, and deducts the constant initial pressure F0 when the blade is not placed to obtain the actual clamping force (F1-F0); the comparison control unit receives the specific clamping force F transmitted by the PC host computer, and compares it with the actual clamping force (F1-F0) obtained by the pressure monitoring unit; according to the comparison result, the movement direction and time of the DC electric push rod are controlled to realize the automatic adjustment of the clamping force, so that the actual clamping force gradually approaches the preset clamping force F; the execution control unit drives the DC electric push rod to move up and down according to the control instruction of the comparison control unit, so as to adjust the clamping force between the upper plate chuck and the lower plate chuck; the communication unit realizes data transmission between the single chip microcomputer and the PC host computer, including receiving the clamping force F set by the PC host computer, and transmitting the current clamping force F2 and the measured electrophysiological signal to the PC host computer. Technical Effects

[0007] The present invention uses closed-loop servo control to automatically adjust the clamping force, and a single-chip microcomputer controls a DC electric push rod for precise adjustment to achieve precise matching with the preset clamping force. This closed-loop control method can automatically adjust the clamping force and reduce the error and labor intensity of manual operation. Free adjustment is achieved by connecting the upper plate chuck with a universal joint: when the upper plate chuck contacts the plant leaf and applies pressure, the upper plate chuck can automatically adjust its position to ensure that the contact surface with the leaf is always horizontal. Regardless of the thickness or shape of the leaf, the uniform distribution of the clamping force can be guaranteed. This design improves the accuracy of the measurement and avoids measurement errors caused by unequal contact surfaces.

[0008] Compared with the prior art, the present invention can control the clamping force more accurately, thereby obtaining more accurate electrophysiological signal data. The automated system significantly reduces the manual adjustment work of the operator during the measurement process, thereby saving a lot of time. Compared with the traditional manual adjustment method, this automated method greatly improves work efficiency and reduces the labor intensity of the operator. The design of the universal joint mechanism enables the device to adapt to blades of various shapes and sizes, improving the flexibility of operation. This design is not only suitable for laboratory environments, but also for variable environmental conditions such as fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of the structure of the device of the present invention;

[0010] Figure 2 It is a schematic diagram of the local structure of the device of the present invention;

[0011] Figure 3 It is a schematic diagram of the local structure of the device of the present invention;

[0012] Figure 4 It is a topological diagram of the present invention;

[0013] Figure 5 It is a flow chart of the present invention;

[0014] Figure 6-Figure 9 This is a physical diagram of the embodiment device;

[0015] In the figure: bracket 1, DC electric push rod 2, universal joint 3, upper electrode plate clamp 4, electrode plate 5, electric wire 6, circular slot 7, lower electrode plate clamp 8, single chip microcomputer 9, pressure sensor 10, handle 11. DETAILED DESCRIPTION

[0016] like Figure 1 , Figure 2 and Figure 3 As shown, the handheld device for automatically measuring the electrophysiological indicators of plants involved in this embodiment includes: an upper plate chuck 4 and a lower plate chuck 8 relatively arranged on a bracket 1, wherein: the upper plate chuck 4 is connected to the bracket 1 through an electric push rod 2 and a universal joint 3, and a pressure sensing mechanism connected to the electric push rod 2 and the single-chip computer 9 is provided in the lower plate chuck 8. When the upper plate chuck 4 contacts the lower plate chuck 8, the electric push rod 2 automatically adjusts the posture of the upper plate chuck 4 through the universal joint 3 and adjusts the clamping force by squeezing the lower plate chuck 8, thereby ensuring that the contact surface remains horizontal and the two chucks are aligned in the vertical direction, so that the leaf to be measured is stably clamped therebetween.

[0017] The bracket 1 is designed with a rectangular frame structure, one side of which is open for easy operation, and the other side is provided with a handle 11 for easy handholding.

[0018] The electric push rod 2 is fixed to the upper end of the bracket 1 and connected to the single chip microcomputer 9 through a driving circuit to achieve stability in the vertical direction.

[0019] The pressure sensing mechanism comprises: an electrode plate 5 and a pressure sensor 10 located thereunder, wherein: the electrode plate 5 is embedded in the center of the upper electrode plate clamp 4 and the lower electrode plate clamp 8 to form a pair of parallel electrode plates aligned in the vertical direction.

[0020] The electrode plate 5 is in contact with the blades and is connected to the single chip computer 9 via the electrical conductor 6 to form a conductive circuit for conducting the electrical signals of the blades.

[0021] The pressure sensor 10 is connected to the single chip microcomputer 9 through a pressure transmitter module to convert the pressure signal into a standard electrical signal. The upper pressure-bearing surface of the pressure sensor 10 contacts the bottom of the lower plate clamp 8 to generate an initial pressure, which needs to be offset when calculating the clamping force.

[0022] The single-chip microcomputer 9 is connected to the PC host computer, receives the specific clamping force value from the PC host computer, and obtains the pressure value of the pressure sensor 10 in real time. The single-chip microcomputer 9 controls the movement direction and time of the electric push rod 2, realizes the synchronous control of the DC electric push rod 2 and the pressure sensor 10, forms a closed-loop servo control, and ensures that the clamping force is basically the same as the preset value.

[0023] The surfaces of the upper plate clamp 4 and the lower plate clamp 8 are provided with slots for setting the electric wire 6, and the LCR tester and the PC host computer are connected through the electric wire 6 to measure the electrophysiological data of the clamped leaf.

[0024] A circular slot 7 for fixing the connecting bracket 1 is provided at the bottom center of the lower plate clamp 8 , and the slot 7 precisely matches the pressure-bearing surface on the upper part of the pressure sensor 10 , ensuring that the lower plate clamp 8 accurately transmits the clamping force to the pressure sensor 10 .

[0025] The inner diameter of the circular clamping groove 7 is greater than or equal to that of the lower plate clamp 8, ensuring that the lower plate clamp 8 will not tilt left or right during operation and always maintain a horizontal state.

[0026] This embodiment relates to a method for detecting plant electrophysiological indicators based on the above device, including:

[0027] 1) Prepare for the test: Connect the LCR tester to the two electrical conductors 6, ensure that the microcontroller 9 and the LCR tester are powered on, and establish a communication connection with the PC host computer.

[0028] 2) Placing the blade: Carefully place the fresh blade to be tested at the center of the lower electrode plate clamp 8, ensuring that the center of the blade is aligned with the center of the parallel electrode plate 5 to obtain optimal electrophysiological signal conduction.

[0029] 3) Input clamping force parameters: Input the predetermined clamping force F value through the PC host computer, and the value will be transmitted to the single chip microcomputer 9 to start the closed loop control program. The specific steps include:

[0030] 3.1) Initial contact: The single chip microcomputer 9 controls the DC electric push rod 2 to move vertically downward to a preset position and lightly contact the surface of the blade to be tested. This step requires preliminary debugging to determine the optimal movement speed and time of the electric push rod 2 to ensure that the clamping force is applied to the blade quickly and evenly.

[0031] 3.2) Pressure detection and conversion: The pressure sensor 10 detects the current pressure value F1, and converts the pressure signal into a standard electrical signal through the pressure transmitter module, and transmits it to the single-chip microcomputer 9. The single-chip microcomputer 9 needs to consider the constant initial pressure F0 generated by the lower plate clamp 8 on the pressure sensor 10 when no blade is placed, and offset it in the calculation.

[0032] 3.3) Clamping force adjustment: The single chip computer 9 compares the difference between the preset clamping force F and the actual clamping force (F1-F0). If F is greater than (F1-F0), the electric push rod 2 continues to move downward to increase the clamping force; if F is less than (F1-F0), the electric push rod 2 moves upward to reduce the clamping force. The single chip computer 9 adjusts the movement time of the electric push rod 2 according to the difference to quickly reach the preset clamping force. When the clamping force difference is within the preset error range, the current clamping force F2 is recorded and the electric push rod 2 is kept stationary for 10 seconds to stabilize the internal physiological condition of the blade.

[0033] 3.4) Electrophysiological signal measurement: The LCR tester measures and obtains the electrophysiological signal of the blade, and transmits it to the PC host computer through the electrical conductor 6. At the same time, the single chip computer 9 sends the current clamping force F2 data to the PC host computer, and controls the electric push rod 2 to reset vertically upward. If the next set of data measurement is required, repeat step 3.1; after all the tests are completed, take out the blade and turn off the equipment.

[0034] After specific actual experiments, the electrophysiological indicators of plants were measured under the specific environment settings of controlled temperature of 25°C, humidity of 60%, and light intensity of 300lu, including two scenes: no leaves and leaves placed. The preset pressure value F was input through the computer program, and then the device automatically executed the pressure control program. The pressure sensor measures and records the actual pressure value F1 in real time. The preset error range of this experiment is 0.15N, that is, when the absolute value of (F1-F) is less than 0.15N, it is considered that the system has reached the preset pressure, the program stops running and records the F1 value. The experimental data are shown in Table 1.

[0035] Table 1 (preset clamping force F, pressure sensor monitoring clamping force F1)

[0036] The experimental results show that the system can reach the set pressure value within the preset error range regardless of whether the leaves are placed or not, indicating that the device can accurately control the clamping force. From the time data, it can be seen that the time from the system starting to reaching the preset pressure and stopping operation is between 26 seconds and 74 seconds. Despite the limitations of hardware accuracy, the device still shows the response speed and stability. These experimental data verify the functional realization of this patented device and prove its effectiveness and accuracy in controlling the clamping force of plant leaves.

[0037] Compared with the prior art, the present invention achieves precise pressure regulation through closed-loop servo control. Experimental data show that the difference between the actual pressure value F1 and the preset pressure value F is within the error range of 0.15N, indicating the high-precision control capability of the device. The system response time recorded in the experiment was as short as 26 seconds and as long as 74 seconds, indicating that the device can quickly reach the preset pressure. Analysis shows that the response time can be further accelerated by improving hardware accuracy and optimizing the control algorithm, which is especially important for application scenarios that require rapid determination of plant electrophysiological indicators. In multiple experiments, whether the leaves were not placed or not, the device was able to stably reach the preset pressure, and the pressure value had a small fluctuation range, showing the high stability and repeatability of the device.

[0038] The above-mentioned specific implementation can be partially adjusted in different ways by those skilled in the art without departing from the principle and purpose of the present invention. The protection scope of the present invention shall be based on the claims and shall not be limited by the above-mentioned specific implementation. Each implementation scheme within its scope shall be subject to the constraints of the present invention.

Claims

1. A handheld device for automatically measuring plant electrophysiological indicators, characterized in that: include: An upper plate chuck and a lower plate chuck are relatively arranged on the bracket, wherein: the upper plate chuck is arranged on the bracket through an electric push rod and a universal joint, a pressure sensing mechanism is arranged in the lower plate chuck, the pressure sensing mechanism and the electric push rod are respectively connected to the single-chip microcomputer, and the upper chuck coincides with the center in the vertical direction when in contact with the lower chuck, and the blade to be tested is clamped between the upper chuck and the lower chuck and the electrophysiological signal of the blade is collected through the LCR tester.

2. The handheld device for automatically measuring plant electrophysiological indicators according to claim 1, characterized in that: The single chip microcomputer comprises: a pressure monitoring unit, a comparison control unit, an execution control unit and a communication unit, wherein: the pressure monitoring unit monitors and obtains the pressure value F1 corresponding to the current clamping force in real time by connecting to a pressure sensor, and deducts the constant initial pressure F0 when the blade is not placed to obtain the actual clamping force (F1-F0); the comparison control unit receives the specific clamping force F transmitted by the PC host computer, and compares it with the actual clamping force (F1-F0) obtained by the pressure monitoring unit; according to the comparison result, the movement direction and time of the DC electric push rod are controlled to realize the automatic adjustment of the clamping force, so that the actual clamping force gradually approaches the preset clamping force F; the execution control unit drives the DC electric push rod to move up and down according to the control instruction of the comparison control unit, so as to adjust the clamping force between the upper plate chuck and the lower plate chuck; the communication unit realizes data transmission between the single chip microcomputer and the PC host computer, including receiving the clamping force F set by the PC host computer, and transmitting the current clamping force F2 and the measured electrophysiological signal to the PC host computer.

3. The handheld device for automatically measuring plant electrophysiological indicators according to claim 1, characterized in that: The bracket is designed with a rectangular frame structure, one side is open for easy operation, and the other side is provided with a handle for easy holding.

4. The handheld device for automatically measuring plant electrophysiological indicators according to claim 1, characterized in that: The electric push rod is fixed to the upper end of the bracket and connected to the single chip microcomputer through a driving circuit to achieve stability in the vertical direction.

5. The handheld device for automatically measuring plant electrophysiological indicators according to claim 1, characterized in that: The pressure sensing mechanism comprises: an electrode plate and a pressure sensor located below the electrode plate, wherein: the electrode plate is embedded in the center of the upper electrode plate clamp and the lower electrode plate clamp to form a pair of parallel electrode plates aligned in the vertical direction; The electrode plate is in contact with the blade and is connected to the single chip computer through an electrical conductor to form a conductive circuit for conducting electrical signals from the blade; The pressure sensor is connected to the single-chip microcomputer through a pressure transmitter module to convert the pressure signal into a standard electrical signal. The upper pressure-bearing surface of the pressure sensor contacts the bottom of the lower plate clamp to generate an initial pressure, which needs to be offset when calculating the clamping force.

6. The handheld device for automatically measuring plant electrophysiological indicators according to claim 1, characterized in that: The single-chip microcomputer is connected to a PC host computer, receives a specific clamping force value from the PC host computer, and obtains the pressure value of the pressure sensor in real time. The single-chip microcomputer controls the movement direction and time of the electric push rod, realizes synchronous control of the DC electric push rod and the pressure sensor, forms a closed-loop servo control, and ensures that the clamping force is basically the same as the preset value.

7. The handheld device for automatically measuring plant electrophysiological indicators according to claim 1, characterized in that: The surfaces of the upper plate clamp and the lower plate clamp are provided with slots for setting electric wires, and the LCR tester and the PC host computer are connected through the electric wires to measure the electrophysiological data of the clamped leaf.

8. The handheld device for automatically measuring plant electrophysiological indicators according to claim 1, characterized in that: A circular slot for fixing the connecting bracket is provided at the bottom center of the lower plate clamp, and the slot is precisely matched with the pressure-bearing surface on the upper part of the pressure sensor to ensure that the lower plate clamp accurately transmits the clamping force to the pressure sensor.

9. The handheld device for automatically measuring plant electrophysiological indicators according to claim 8, characterized in that: The inner diameter of the circular clamping groove is greater than or equal to that of the lower plate clamp, ensuring that the lower plate clamp will not tilt left or right during operation and always maintain a horizontal state.

10. A method for detecting plant electrophysiological indicators based on the device according to any one of claims 1 to 9, characterized in that: include: 1) Prepare for the test: Connect the LCR tester to two electrical wires, ensure that the power of the microcontroller and the LCR tester are turned on, and establish a communication connection with the PC host computer; 2) Place the leaf: Carefully place the fresh leaf to be tested in the center of the lower electrode chuck, ensuring that the center of the leaf is aligned with the center of the parallel electrode plate to obtain the best electrophysiological signal conduction; 3) Input clamping force parameters: Input the predetermined clamping force F value through the PC host computer, which will be transmitted to the microcontroller to start the closed-loop control program. The specific steps include: 3.1) Initial contact: The single chip microcomputer controls the DC electric push rod to move vertically downward to the preset position and gently contact the surface of the blade to be tested; this step requires preliminary debugging to determine the optimal movement speed and time of the electric push rod to ensure that the clamping force is applied to the blade quickly and evenly; 3.2) Pressure detection and conversion: The pressure sensor detects the current pressure value F1, and converts the pressure signal into a standard electrical signal through the pressure transmitter module and transmits it to the single-chip microcomputer; the single-chip microcomputer needs to consider the constant initial pressure F0 generated by the lower plate chuck on the pressure sensor when the blade is not placed, and offset it in the calculation; 3.3) Clamping force adjustment: The single chip microcomputer compares the difference between the preset clamping force F and the actual clamping force (F1-F0); if F is greater than (F1-F0), the electric push rod continues to move downward to increase the clamping force; if F is less than (F1-F0), the electric push rod moves upward to reduce the clamping force; the single chip microcomputer adjusts the movement time of the electric push rod according to the difference to quickly reach the preset clamping force; when the clamping force difference is within the preset error range, the current clamping force F2 is recorded and the electric push rod is kept stationary for 10 seconds to stabilize the internal physiological condition of the blade; 3.4) Electrophysiological signal measurement: The LCR tester measures and obtains the electrophysiological signal of the blade, and transmits it to the PC host computer through the electrical wire; at the same time, the single chip microcomputer sends the current clamping force F2 data to the PC host computer, and controls the electric push rod to reset vertically upward; if the next set of data measurement is required, repeat step 3.1; after all tests are completed, take out the blade and turn off the equipment.

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