A data acquisition device for plant bioelectricity and water transport parameters

Abstract

The present invention relates to a data acquisition device for plant bioelectricity and water transfer parameters, and its technical features are: comprising a control unit, a data sensing unit, a data transmission unit, a timing unit, a function configuration unit, a system status output unit, an expansion unit and a power supply unit. The present invention can set a data sampling trigger mode and a sampling period to improve data accuracy and real-time performance; can automatically adjust the power supply mode to reduce system power consumption; can automatically track and output the system status to facilitate system maintenance; and has high functional integration and convenient operation, providing a tool for plant electrophysiological research.

Description

Technical Field

[0001] The invention belongs to the technical field of data acquisition, and relates to a data acquisition device for bioelectricity and water transfer parameters, in particular to a data acquisition device for plant bioelectricity and water transfer parameters. Background Art

[0002] There is a continuously changing potential difference between the plant stem and the soil where it grows (or different longitudinal positions of the plant stem). This potential difference change may be related to plant water utilization and transport, but the specific relationship is still unclear. In order to explore the relationship between the potential difference change and water transport parameters (transpiration rate, stem flow rate, root water absorption) and reveal the mechanism of potential difference change, it is necessary to obtain long-term, continuous and synchronous potential difference, water transport parameters and environmental parameters. Existing studies usually use voltmeters, plant water transport measurement devices (transpiration meters, stem flow meters, water absorption measurement devices) and meteorological parameter measurement instruments to measure and record relevant data, and each parameter is measured separately.

[0003] In the real-time measurement of plant water transfer parameters, stem flow measurement method and weighing measurement method are usually used. The stem flow measurement method (stem flow meter) requires the layout of electrodes in the plant stems, and the measurement of bioelectric signals also requires the layout of electrodes in the plant stems. There is a potential influence between the two. Therefore, weighing measurement methods (such as potted weighing method and communicating vessel method) are more suitable for experimental research in this field. The weighing measurement method refers to placing the plant in a culture container and measuring the weight of the container to measure the plant water transfer parameters. The rate of plant water utilization varies with plant species and growth stage. The magnitude of water absorption, transmission, and loss per unit time varies significantly, and the accuracy of the measurement results is sensitive to the sampling time interval.

[0004] Typical weighing methods include: Figure 3 The pot weighing method shown and Figure 4 The communicating vessel method shown:

[0005]

Pot weighing method

[0006] ①Put the plant in a plant culture container, and place the plant culture container on the pressure sensor;

[0007] ② Seal the top of the plant culture container to prevent water evaporation. Water can only be lost through the plant body through transpiration;

[0008] ③ Read the measured value of the pressure sensor and calculate the change ΔW of the measured value per unit time, which is approximately equal to the transpiration of the plant per unit time;

[0009] ④ Calculate the ratio of ΔW to the area of ​​the plant sapwood, which is the stem flow rate.

[0010]

Connecting Vessel Method

[0011] ① The plant culture container 1 and the plant culture container 2 are connected, the plant is placed in the plant culture container 2, and the plant culture container 1 and the plant culture container 2 are placed on the pressure sensor 1 and the pressure sensor 2 respectively;

[0012] ② Seal the upper ends of the plant culture container 1 and the plant culture container 2 to prevent water evaporation. Water can only be lost through the plant body by transpiration;

[0013] ③ Read the measured values ​​of pressure sensor 1 and pressure sensor 2, and calculate the change in the measured values ​​per unit time ΔW 1 and ΔW 2 The transpiration of plants per unit time is E r =ΔW 1 +ΔW 2 ;

[0014] ④Calculate E r The ratio of the area of ​​the plant sapwood is the stem flow rate;

[0015] ⑤Calculate the amount of water absorbed by plants per unit time

[0016] Among them A 1 and A 2 are the water surface areas of the plant cultivation container 1 and the plant cultivation container 2 respectively.

[0017] However, the existing data acquisition devices for the above two weighing methods have fixed sampling cycles and cannot guarantee the accuracy of the data; they also have the defects of low operational convenience and high system power consumption. Moreover, when using the above devices to collect various data such as plant bioelectricity and water transport parameters, the various data collected cannot be strictly synchronized and the data acquisition function is not highly integrated, which will have a certain impact on the accuracy of the experimental results. Summary of the invention

[0018] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide a data acquisition device for plant bioelectricity and water transport parameters which has a reasonable design, synchronous data acquisition, and high data accuracy.

[0019] The present invention solves the practical problem by adopting the following technical solutions:

[0020] A data acquisition device for plant bioelectricity and water transfer parameters, comprising a control unit, a data sensing unit, a data transmission unit, a timing unit, a function configuration unit, a system status output unit, an expansion unit and a power supply unit;

[0021] The input end of the control unit is connected to the data sensing unit for receiving the detection data collected by the data sensing unit in real time; the control unit is also connected to a remote server or terminal through a data transmission unit for two-way communication; the input end of the control unit is also connected to the timing unit for adding timestamp information to the data acquired by the data sensing unit; the input end of the control unit is also connected to the function configuration unit for receiving function configuration instructions input by a user; the output end of the control unit is also connected to the system status output unit for outputting the system status code compiled by the control unit to the user; the output end of the control unit is also connected to the extension unit for connecting to an external device; the output end of the power supply unit is respectively connected to the control unit, the data sensing unit, the data transmission unit, the timing unit, the function configuration unit, the system status output unit and the extension unit, and supplies power to them.

[0022] Moreover, the control unit includes a microcontroller and an analog-to-digital converter; the data sensing unit includes a power monitoring module, a bioelectric signal measurement module, an environmental temperature and humidity measurement module, a soil temperature and humidity measurement module, a light intensity measurement module and a moisture transmission parameter measurement module;

[0023] The power supply monitoring module includes a power supply voltage sampling circuit and an impedance conversion circuit connected together, and its output end is connected to a microcontroller through an analog-to-digital converter to monitor the power supply voltage;

[0024] The bioelectric signal measurement module includes a bioelectric signal interface, an amplifier and a low-pass filter connected together in multiple ways, and its output end is connected to a microcontroller through an analog-to-digital converter, and is used to collect the potential difference between any point on the plant stem and the soil, or the potential difference between any two points in the longitudinal direction of the plant stem, and output it to the microcontroller after analog-to-digital conversion;

[0025] The ambient temperature and humidity measurement module includes a temperature and humidity measurement circuit, the output end of which is connected to a microcontroller via an analog-to-digital converter or a bus interface to collect ambient temperature and humidity;

[0026] The soil temperature and humidity measurement module includes a temperature and humidity measurement circuit, the output end of which is connected to a microcontroller via an analog-to-digital converter or a bus interface to collect soil temperature and humidity;

[0027] The light intensity measurement module includes a light intensity measurement circuit, the output end of which is connected to a microcontroller via an analog-to-digital converter or a bus interface for collecting light intensity;

[0028] The moisture transmission parameter measurement module includes two pressure sensors, whose output ends are connected to a microcontroller via an analog-to-digital converter or a bus interface, and are used to measure moisture transmission parameters;

[0029] Moreover, the data transmission unit is connected to the control unit, and the data transmission unit includes a mobile network access circuit electrically connected to the control unit, and can connect to a remote server or terminal through a mobile network and perform two-way communication.

[0030] Moreover, the output end of the timing unit is connected to the control unit. The timing unit includes an NTP server access circuit electrically connected to the control unit, which can connect to the NTP server through a mobile network and obtain a standard clock to add timestamp information to the data obtained by the data sensing unit.

[0031] Moreover, the functional configuration unit includes a communication interface electrically connected to the control unit, and its output end is connected to the control unit, for outputting the data sampling trigger mode instructions, sampling cycle instructions, moisture transmission parameter measurement method selection instructions and pressure sensor selection instructions input by the user to the control unit.

[0032] Furthermore, the system status output unit comprises a communication interface electrically connected to the control unit, an input end of which is connected to the control unit for outputting the system status code compiled by the control unit to the user.

[0033] Furthermore, the expansion unit comprises a general I / O port of the microcontroller, an analog-to-digital converter interface, an I2C interface, an SPI interface and a UART interface for connecting with external devices.

[0034] Moreover, the power supply unit includes a 5.0V power supply, a first 3.3V power supply and a second 3.3V power supply; wherein the 5.0V power supply is used to power the data transmission unit and the timing unit; the first 3.3V power supply is used to power the control unit, the function configuration unit and the system status output unit; the second 3.3V power supply is a controllable power supply, which is controlled to be turned on or off by the control unit, and the second 3.3V power supply is used to power the data sensing unit and the expansion unit.

[0035] Advantages and beneficial effects of the present invention:

[0036] The present invention proposes a data acquisition device for studying the relationship between plant bioelectricity and water transfer parameters. The device integrates a bioelectric signal measurement circuit, an environmental temperature and humidity measurement circuit, a soil temperature and humidity measurement circuit, a light intensity measurement circuit, a water transfer parameter measurement circuit, a data transmission circuit, a function configuration interface, a power supply monitoring and control circuit, and a system status output interface. The device can automatically, continuously, and synchronously collect plant bioelectric signals, water transfer parameters (transpiration rate, stem flow rate, root water absorption) and environmental parameters, and send the data to a remote server or terminal; it can set a data sampling trigger mode and a sampling period to improve data accuracy and real-time performance; it can automatically adjust the power supply mode to reduce system power consumption; it can automatically track and output the system status to facilitate system maintenance; it has high functional integration and is easy to operate, providing a tool for plant electrophysiological research. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A circuit block diagram of a data acquisition device for studying the relationship between plant bioelectricity and water transport parameters according to the present invention;

[0038] FIG. 2( a ) is a schematic diagram of the present invention. Figure 1 Circuit diagram of the control unit;

[0039] FIG. 2( b ) is a schematic diagram of the present invention. Figure 1 Circuit diagram of the data sensing unit in the figure;

[0040] FIG. 2( c ) is a schematic diagram of the present invention. Figure 1 Circuit diagram of data transmission unit and timing unit;

[0041] FIG. 2( d ) is a schematic diagram of the present invention. Figure 1 Circuit diagram of the function configuration unit and the system status output unit;

[0042] FIG. 2( e ) is a schematic diagram of the present invention. Figure 1 Circuit diagram of the expansion unit;

[0043] FIG. 2( f ) is a schematic diagram of the present invention. Figure 1 Circuit diagram of the power supply unit;

[0044] Figure 3 It is a schematic diagram of the principle of the potted plant weighing method in the background technology of the present invention;

[0045] Figure 4 It is a schematic diagram of the principle of the communicating vessel method in the background technology of the present invention;

[0046] Figure 5 It is a schematic diagram of the function configuration instructions of the present invention;

[0047] Figure 6 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0048] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings:

[0049] A data acquisition device for studying the relationship between plant bioelectricity and water transport parameters, such as Figure 1 As shown, it includes a control unit, a data sensing unit, a data transmission unit, a timing unit, a function configuration unit, a system status output unit, an expansion unit and a power supply unit;

[0050] The input end of the control unit is connected to the data sensing unit for receiving the detection data collected by the data sensing unit in real time; the control unit is also connected to a remote server or terminal through a data transmission unit for two-way communication; the input end of the control unit is also connected to the timing unit for adding timestamp information to the data acquired by the data sensing unit; the input end of the control unit is also connected to the function configuration unit for receiving function configuration instructions input by a user; the output end of the control unit is also connected to the system status output unit for outputting the system status code compiled by the control unit to the user; the output end of the control unit is also connected to the extension unit for connecting to an external device; the output end of the power supply unit is respectively connected to the control unit, the data sensing unit, the data transmission unit, the timing unit, the function configuration unit, the system status output unit and the extension unit, and supplies power to them.

[0051] In this embodiment, the control unit includes a microcontroller and an analog-to-digital converter; the data sensing unit includes a power monitoring module, a bioelectric signal measurement module, an environmental temperature and humidity measurement module, a soil temperature and humidity measurement module, a light intensity measurement module, and a moisture transmission parameter measurement module;

[0052] The power supply monitoring module includes a power supply voltage sampling circuit and an impedance conversion circuit connected together, and its output end is connected to a microcontroller through an analog-to-digital converter to monitor the power supply voltage;

[0053] The bioelectric signal measurement module includes three connected bioelectric signal interfaces, an amplifier and a low-pass filter, the output end of which is connected to a microcontroller via an analog-to-digital converter, and is used to collect the potential difference between any point on the plant stem and the soil, or the potential difference between any two points in the longitudinal direction of the plant stem, and output it to the microcontroller after analog-to-digital conversion;

[0054] The ambient temperature and humidity measurement module includes a temperature and humidity measurement circuit, the output end of which is connected to a microcontroller via an analog-to-digital converter or a bus interface to collect ambient temperature and humidity;

[0055] The soil temperature and humidity measurement module includes a temperature and humidity measurement circuit, the output end of which is connected to a microcontroller via an analog-to-digital converter or a bus interface to collect soil temperature and humidity;

[0056] The light intensity measurement module includes a light intensity measurement circuit, the output end of which is connected to a microcontroller via an analog-to-digital converter or a bus interface for collecting light intensity;

[0057] The moisture transmission parameter measurement module includes two pressure sensors, whose output ends are connected to a microcontroller via an analog-to-digital converter or a bus interface, and are used to measure moisture transmission parameters;

[0058] In this embodiment, the data transmission unit is connected to the control unit, and the data transmission unit includes a mobile network access circuit electrically connected to the control unit, and can connect to a remote server or terminal through a mobile network and perform two-way communication.

[0059] In this embodiment, the output end of the timing unit is connected to the control unit. The timing unit includes an NTP server access circuit electrically connected to the control unit, which can connect to the NTP server through a mobile network and obtain a standard clock to add timestamp information to the data obtained by the data sensing unit.

[0060] In this embodiment, the functional configuration unit includes a communication interface electrically connected to the control unit, and its output end is connected to the control unit, for outputting the data sampling trigger mode instructions, sampling cycle instructions, moisture transmission parameter measurement method selection instructions and pressure sensor selection instructions input by the user to the control unit.

[0061] In this embodiment, the system status output unit includes a communication interface electrically connected to the control unit, and an input end thereof is connected to the control unit for outputting the system status code compiled by the control unit to the user.

[0062] In this embodiment, the expansion unit includes a general I / O port of the microcontroller, an analog-to-digital converter interface, an I2C interface, an SPI interface and a UART interface for connecting to an external device.

[0063] In this embodiment, the power supply unit includes a 5.0V power supply, a first 3.3V power supply and a second 3.3V power supply; wherein, the 5.0V power supply is used to power the data transmission unit and the timing unit; the first 3.3V power supply is used to power the control unit, the function configuration unit and the system status output unit; the second 3.3V power supply is a controllable power supply, which is controlled to be turned on or off by the control unit, and the second 3.3V power supply is used to power the data sensing unit and the expansion unit.

[0064] The following is a further description of the composition, function and role of each module:

[0065] The control unit includes a microcontroller and its peripheral circuits, and may also include an analog-to-digital converter, which is electrically connected to a data sensing unit, a data transmission unit, a timing unit, a function configuration unit, a system status output unit, an expansion unit, and a power supply unit to parse user instructions, process data, and control each unit to work normally.

[0066] The data sensing unit includes a power supply monitoring module, a bioelectric signal measurement module, an environmental temperature and humidity measurement module, a soil temperature and humidity measurement module, a light intensity measurement module, and a moisture transmission parameter measurement module.

[0067] The power supply monitoring module includes a power supply voltage sampling circuit and an impedance conversion circuit connected together, and is connected to the control unit through an analog-to-digital converter.

[0068] The bioelectric signal measurement module includes three connected bioelectric signal interfaces, an amplifier and a low-pass filter, and is connected to the control unit through an analog-to-digital converter. The bioelectric signal refers to the potential difference between any point on the plant stem and the soil, or the potential difference between any two points in the longitudinal direction of the plant stem.

[0069] The environmental temperature and humidity measurement module includes a temperature and humidity measurement circuit, which is connected to the microcontroller through an analog-to-digital converter or a bus interface.

[0070] The soil temperature and humidity measurement module includes a temperature and humidity measurement circuit, which is connected to the microcontroller through an analog-to-digital converter or a bus interface.

[0071] The light intensity measurement module comprises a light intensity measurement circuit, which is connected to the microcontroller via an analog-to-digital converter or a bus interface.

[0072] The water transfer parameter measurement module includes two pressure sensors, which are connected to the microcontroller through an analog-to-digital converter or a bus interface, and support either a potted plant weighing method or a communicating vessel method.

[0073] The data transmission unit includes a mobile network access circuit electrically connected to the control unit, and can connect to a remote server or terminal via a mobile network and perform two-way communication.

[0074] The timing unit includes an NTP server access circuit electrically connected to the control unit, which can connect to the NTP server through a mobile network and obtain a standard clock to add timestamp information to the data obtained by the data perception unit.

[0075] The function configuration unit includes a communication interface electrically connected to the control unit, which can receive the function configuration instructions input by the user and transmit them to the control unit. The function configuration instructions include data sampling trigger mode instructions, sampling period instructions, moisture transmission parameter measurement method selection instructions, and pressure sensor selection instructions, which are used to specify the data sampling trigger mode, sampling period, moisture transmission parameter measurement method, and pressure sensor used. Among them, the sampling trigger mode includes two modes: fixed period mode and pressure trigger mode. The fixed period mode means that the data perception unit samples the data at a fixed time interval, wherein the time interval is determined by the sampling period instruction; the pressure trigger mode means that when the output value of any pressure sensor changes, the data perception unit immediately completes a data sampling. The moisture transmission parameter measurement method includes a potted weighing method and a communicating vessel method. When using the potted weighing method, any pressure sensor can be selected.

[0076] The system status output unit includes a communication interface electrically connected to the control unit, and can output the system status code compiled by the control unit to the user.

[0077] The expansion unit includes a general I / O port of the microcontroller, an analog-to-digital converter interface, an I2C interface, an SPI interface, and a UART interface.

[0078] The power supply unit includes a 5.0V power supply, a first 3.3V power supply, and a second 3.3V power supply. The second 3.3V power supply is a controllable power supply that can be turned on or off by the control unit. The 5.0V power supply is used to supply power to the data transmission unit and the timing unit; the first 3.3V power supply is used to supply power to the control unit, the function configuration unit, and the system status output unit; the second 3.3V power supply is used to supply power to the data sensing unit and the expansion unit.

[0079] like Figure 1As shown, the present invention provides a data acquisition device for studying the relationship between plant bioelectricity and water transmission parameters, including a control unit, a data sensing unit, a data transmission unit, a timing unit, a function configuration unit, a system state output unit, an extension unit, and a power supply unit. The control unit is electrically connected to the data sensing unit, the data transmission unit, the timing unit, the function configuration unit, the system state output unit, the extension unit, and the power supply unit to parse user instructions, process data, and control each unit to work normally; the data sensing unit is used to collect data and transmit the data to the control unit for processing; the data transmission unit is used to send the data to a remote server or terminal; the timing unit is used to connect to the NTP server and obtain the standard clock, and add timestamp information to the data obtained by the data sensing unit; the function configuration unit is used to receive the function configuration instruction input by the user and transmit it to the control unit; the system state output unit is used to output system state information for system maintenance; the extension unit is used to lead out a general digital I / O port, an analog-to-digital converter interface, an I2C interface, an SPI interface, and a UART interface for use in expanding system functions; the power supply unit is used to power the control unit, the data sensing unit, the data transmission unit, the timing unit, the function configuration unit, the system state output unit, and the extension unit.

[0080] As shown in FIG2(a), the control unit includes a microcontroller MSP430F147 and its peripheral circuits, and is electrically connected to a data sensing unit, a data transmission unit, a timing unit, a function configuration unit, a system status output unit, an expansion unit, and a power supply unit.

[0081] As shown in Figure 2(b), the data sensing unit includes a power monitoring module, a bioelectric signal measurement module, an environmental temperature and humidity measurement module, a soil temperature and humidity measurement module, a light intensity measurement module, and a moisture transmission parameter measurement module.

[0082] Power supply monitoring module: Resistors RS12 and RS13 form a power supply voltage sampling circuit, whose output voltage is 1 / 6 of the power supply voltage; integrated operational amplifier UO1A and resistor RS11 form a voltage follower for impedance conversion, whose output signal is received by the control unit through an analog-to-digital converter. The integrated operational amplifier model is OPA2333.

[0083] Bioelectric signal measurement module: BIO-VOLTAGE is a three-way bioelectric signal interface; the integrated operational amplifiers UO1B, UO2A, and UO2B and the surrounding resistors and capacitors form three-way proportional amplifiers and three-way low-pass filters for signal conditioning, and their output signals are received by the control unit through the analog-to-digital converter. The integrated operational amplifier model is OPA2333.

[0084] Environmental temperature and humidity measurement module: The sensor BME280 and the surrounding resistors and capacitors form a temperature and humidity measurement circuit, and transmit the measured values ​​to the control unit via the I2C bus or SPI bus. In addition, the module can also measure atmospheric pressure.

[0085] Soil temperature and humidity measurement module: includes temperature and humidity sensor interface SOIL, which transmits the measured value to the control unit through I2C bus. The temperature and humidity sensor can be any one of SHT10, SHT11, SHT15, and waterproof.

[0086] Light intensity measurement module: includes photoresistor RL1 and signal conditioning circuit (resistor RL2, capacitor CL1), and its output signal is received by the control unit through the analog-to-digital converter.

[0087] Moisture transfer parameter measurement module: includes two pressure sensors with HX711, which transmit the measured values ​​to the control unit via a single bus. Applicable to pot weighing method and communicating vessel method. When using pot weighing method, any pressure sensor can be selected.

[0088] As shown in Figure 2(c), the data transmission unit includes SIM800C (UG) and its peripheral circuits, which are connected to the control unit through the UART interface. The control unit controls SIM800C to turn on and off, switch working modes, connect or disconnect remote servers or terminals, and transmit data through AT commands. The basic process of a data transmission is shown in Table 1.

[0089] Table 1 Data transmission process

[0090]

[0091]

[0092] As shown in Figure 2(c), the timing unit shares hardware resources with the data transmission unit, including SIM800C (UG) and its peripheral circuits, which are connected to the control unit through the UART interface. The control unit controls SIM800C to connect to the NTP server through AT commands and obtain the standard clock. The standard clock is used to add timestamp information to the data. The basic timing process is shown in Table 2.

[0093] Table 2 Timing process

[0094]

[0095] As shown in Figure 2(d), the function configuration unit includes a UART interface, which is connected to UART1 of the microcontroller MSP430F147. The function configuration unit can receive function configuration instructions input by the user, and the instructions are received and processed by the microcontroller. The function configuration instructions are used to specify the data sampling trigger mode, sampling period, moisture transmission parameter measurement method, and the pressure sensor used. The user can enter the instructions through the serial port tool. The function configuration instruction is a 16-bit binary number, including four parts: data sampling trigger mode instruction, sampling period instruction, moisture transmission parameter measurement method selection instruction, and pressure sensor selection instruction. Among them, bits 0-5 are sampling period instructions, bits 6-7 are data sampling trigger mode instructions, bits 8-13 are pressure sensor selection instructions, and bits 14-15 are moisture transmission parameter measurement method selection instructions. Figure 5 As shown. The data sampling trigger mode includes two modes: fixed cycle mode and pressure trigger mode. Fixed cycle mode means that the data sensing unit samples data at a fixed time interval, where the time interval is determined by the sampling cycle instruction; pressure trigger mode means that when the output value of any pressure sensor changes, the data sensing unit immediately completes a data sampling. The water transfer parameter measurement methods include potted weighing method and communicating vessel method. When using the potted weighing method, any pressure sensor can be selected; when using the communicating vessel method, two pressure sensors need to be selected at the same time. The function configuration method is shown in Table 3 and Table 4.

[0096] Table 3 Function configuration method (lower 8 bits of function configuration instruction)

[0097]

[0098] Table 4 Function configuration method (high 8 bits of function configuration instruction)

[0099]

[0100] As shown in Figure 2(d), the system status output unit shares hardware resources with the function configuration unit, including the UART interface, which is connected to the UART1 of the microcontroller MSP430F147. The control unit compiles and outputs information based on the system status, which can be read by the user through the serial port tool.

[0101] As shown in Figure 2(e), the expansion unit includes an analog-to-digital converter interface, a UART interface, and some I / O ports of the microcontroller MSP430F147. Each interface can be reused as an I2C interface and an SPI interface. The expansion unit can be used to expand system functions.

[0102] As shown in Figure 2(f), the power supply unit includes a main power interface (POWER), a 5.0V power supply, a first 3.3V power supply (VCC), and a second 3.3V power supply. The 5.0V power supply includes a switching regulator LM2576-5.0 and its peripheral circuits, which can provide a 5.0V / 3A output to power the data transmission unit and the timing unit; the first 3.3V power supply includes a low-voltage dropout linear regulator MIC5219-3.3 and its peripheral circuits, which can provide a 3.3V / 500mA output to power the control unit, the function configuration unit, and the system status output unit; the second 3.3V power supply includes a low-voltage dropout linear regulator MIC5219-3.3 and its peripheral circuits, which can provide a 3.3V / 500mA output to power the data sensing unit and the expansion unit. The second 3.3V power supply is controlled by the control unit through the EN pin of MIC5219-3.3. When the EN pin is pulled high, the power supply is turned on, otherwise it is turned off.

[0103] Figure 6 The system workflow is shown in Figure 1. After the device is started, the system is initialized first, including the general input and output interface of the microcontroller, the asynchronous transceiver, the timer, the analog-to-digital converter and the interrupt. Then the GPRS module SIM800C is started. After the GPRS module is successfully started, the clock is synchronized with the NTP server. Then the function configuration instruction is read and the second 3.3V power supply is turned on. After that, the NTP standard clock is obtained to obtain the data collection time, and a data collection is completed, including the power supply voltage, bioelectric signal, ambient temperature and humidity, soil temperature and humidity, and light intensity. Finally, the data is formatted and sent to the remote server or terminal. After that, if the system is set to a fixed cycle mode, it enters the sleep state and turns on the timer to prepare for the next working cycle; otherwise, the output value of the pressure sensor is monitored to see if it changes, and it is ready to enter the next working cycle. All the above links have system status information output.

[0104] It should be emphasized that the embodiments of the present invention are illustrative rather than restrictive. Therefore, the present invention includes but is not limited to the embodiments described in the specific implementation modes. Any other implementation modes derived by those skilled in the art based on the technical solutions of the present invention also fall within the scope of protection of the present invention.

Claims

1. A data acquisition device for plant bioelectricity and water transport parameters, characterized in that: It includes a control unit, a data sensing unit, a data transmission unit, a timing unit, a function configuration unit, a system status output unit, an expansion unit and a power supply unit; The input end of the control unit is connected to the data sensing unit for receiving the detection data collected by the data sensing unit in real time; the control unit is also connected to a remote server or terminal through a data transmission unit and performs two-way communication; the input end of the control unit is also connected to the timing unit for adding timestamp information to the data acquired by the data sensing unit; the input end of the control unit is also connected to the function configuration unit for receiving the function configuration instruction input by the user; the output end of the control unit is also connected to the system status output unit for outputting the system status code compiled by the control unit to the user; the output end of the control unit is also connected to the extension unit for connecting to an external device; the output end of the power supply unit is respectively connected to the control unit, the data sensing unit, the data transmission unit, the timing unit, the function configuration unit, the system status output unit and the extension unit, and supplies power to them; The control unit includes a microcontroller and an analog-to-digital converter; the data sensing unit includes a power monitoring module, a bioelectric signal measurement module, an environmental temperature and humidity measurement module, a soil temperature and humidity measurement module, a light intensity measurement module and a moisture transmission parameter measurement module; the power monitoring module includes a power supply voltage sampling circuit and an impedance conversion circuit connected together, and its output end is connected to the microcontroller through an analog-to-digital converter for monitoring the power supply voltage; the bioelectric signal measurement module includes a multi-channel bioelectric signal interface, an amplifier and a low-pass filter connected together, and its output end is connected to the microcontroller through an analog-to-digital converter for collecting the potential difference between any point on the plant stem and the soil, or the potential difference between any two points in the longitudinal direction of the plant stem, and outputs it to the microcontroller after analog-to-digital conversion; the environmental temperature and humidity measurement module includes a temperature and humidity measurement circuit, and its output end is connected to the microcontroller through an analog-to-digital converter or a bus interface for collecting environmental temperature and humidity; the soil temperature and humidity measurement module includes a temperature and humidity measurement circuit, and its output end is connected to the microcontroller through an analog-to-digital converter or a bus interface for collecting soil temperature and humidity; The light intensity measurement module includes a light intensity measurement circuit, whose output end is connected to a microcontroller through an analog-to-digital converter or a bus interface, and is used to collect light intensity; the moisture transmission parameter measurement module includes two pressure sensors, whose output end is connected to a microcontroller through an analog-to-digital converter or a bus interface, and is used to measure moisture transmission parameters; The data transmission unit is connected to the control unit, and the data transmission unit includes a mobile network access circuit electrically connected to the control unit, and can connect to a remote server or terminal through a mobile network and perform two-way communication; The output end of the timing unit is connected to the control unit. The timing unit includes an NTP server access circuit electrically connected to the control unit, which can connect to the NTP server through a mobile network and obtain a standard clock to add timestamp information to the data obtained by the data sensing unit; The function configuration unit includes a communication interface electrically connected to the control unit, and an output end thereof is connected to the control unit, and is used to output the data sampling trigger mode instruction, sampling period instruction, moisture transmission parameter measurement method selection instruction and pressure sensor selection instruction input by the user to the control unit; The data sampling trigger mode includes two modes: fixed cycle mode and pressure trigger mode; the fixed cycle mode means that the data sensing unit samples data at a fixed time interval, wherein the time interval can be specified by the user; the pressure trigger mode means that when the output value of any pressure sensor changes, the data sensing unit immediately completes a data sampling; the measurement method of the moisture transmission parameter measurement module includes two methods: potted plant weighing method and communicating vessel method; when using the potted plant weighing method, any pressure sensor can be selected; when using the communicating vessel method, two pressure sensors can be selected at the same time; The function configuration instruction is a 16-bit binary number, including four parts: data sampling trigger mode instruction, sampling cycle instruction, moisture transmission parameter measurement method selection instruction, and pressure sensor selection instruction; bits 0 to 5 of the function configuration instruction are sampling cycle instructions. In the fixed cycle mode, any value between 000001 and 111111 can be used, and its decimal value represents the sampling cycle in minutes; it is configured to 000000 in the pressure trigger mode; bits 6 to 7 of the function configuration instruction are data sampling trigger mode instructions. When configured to 00, the pressure trigger mode is enabled, and when configured to 01, the fixed cycle mode is enabled; bits 8 to 13 of the function configuration instruction are pressure sensor selection instructions. When configured to 000001, the first pressure sensor is selected, when configured to 000010, the second pressure sensor is selected, and when configured to 000000, both pressure sensors are selected; bits 14 to 15 of the function configuration instruction are moisture transmission parameter measurement method selection instructions. When configured to 00, the communicating vessel method is selected, and when configured to 01, the potted plant weighing method is selected; The system status output unit includes a communication interface electrically connected to the control unit, an input end of which is connected to the control unit and is used to output the system status code compiled by the control unit to the user; The expansion unit includes a general I / O port of the microcontroller, an analog-to-digital converter interface, an I2C interface, an SPI interface and a UART interface for connecting to an external device; The power supply unit includes a 5.0V power supply, a first 3.3V power supply and a second 3.3V power supply; wherein the 5.0V power supply is used to power the data transmission unit and the timing unit; the first 3.3V power supply is used to power the control unit, the function configuration unit and the system status output unit; the second 3.3V power supply is a controllable power supply, which is turned on or off by the control unit, and the second 3.3V power supply is used to power the data sensing unit and the expansion unit.

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