Calibration system of microplate incubator based on Internet of Things communication

Abstract

The invention discloses a calibration system of a microplate incubator based on Internet of Things communication, which belongs to the technical field of intelligent sensing, comprises an upper computer, a data acquisition unit, a rotating speed sensor and a temperature acquisition device, and solves the technical problem of accurately acquiring multi-point temperature data and rotating speed data of the microplate incubator in real time through the Internet of Things technology. The influence of lead resistance is eliminated, the temperature measurement precision can reach + / -0.1 DEG C, multi-point synchronous monitoring is supported, the temperature uniformity of the microwell plate incubator can be comprehensively evaluated, non-contact measurement is adopted, the precision reaches + / -0.1%, mechanical interference is avoided, manual intervention is reduced, the calibration efficiency is improved, the double-communication channel complementary design of WIFI and LORA is adopted, and the calibration accuracy is improved. The system adapts to the complex electromagnetic environment of a laboratory, ensures the stability of data transmission, and can be flexibly deployed or expanded in function due to the independent design of a data collector and a temperature collection device.

Description

Technical Field

[0001] The present invention belongs to the field of intelligent sensing technology, and in particular relates to a calibration system for a microplate incubator based on Internet of Things communication. Background Art

[0002] A microplate incubator is a constant temperature oscillating device widely used in biomedical, chemical, and industrial experiments. Its core function is to provide a stable environment for experiments such as microbial fermentation, cell culture, and enzyme reactions (such as PCR amplification and gene cloning) through precise temperature control and oscillation mixing.

[0003] At present, microplate incubators mostly use PID control technology, high-performance sensors and air bath heating methods. They have high temperature stability (small fluctuations) and good uniformity, support rapid heating and long-term constant temperature operation, and are generally equipped with a touch screen or LCD display interface. They support parameter setting (temperature, time, speed), power failure recovery, timed alarm and other functions. They are easy to operate and have a high degree of automation. They are compatible with various specifications of microplates (24 / 48 / 96 wells, etc.), meet the needs of high-throughput experiments, and have an oscillation mixing function, which can simultaneously perform cell suspension culture and reaction.

[0004] At present, domestic microplate incubator technology has matured, and the temperature control and oscillation accuracy have reached international standards. It is widely used in medical diagnosis, drug development and basic scientific research.

[0005] However, despite the rapid development of microplate incubator technology, there is currently no multifunctional calibration equipment for microplate incubators in China, and it is impossible to systematically evaluate key parameters such as temperature indication error, uniformity and speed accuracy. The existing calibration method relies on general temperature control instruments (such as single-point thermometers), which are difficult to simulate the actual use scenarios of microplates, resulting in insufficient reliability of measurement traceability. Existing equipment cannot monitor the dynamic changes of temperature fluctuations and oscillation speed in real time during operation, affecting the reproducibility and accuracy of experimental data. Summary of the Invention

[0006] The purpose of the present invention is to provide a calibration system for a microplate incubator based on Internet of Things communication, which solves the technical problem of accurately collecting multi-point temperature data and rotation speed data of a microplate incubator in real time through Internet of Things technology.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A microplate incubator calibration system based on Internet of Things communication includes a host computer, a data collector, a speed sensor, and a temperature acquisition device. The temperature acquisition device and the data collector communicate via a LORA network or a WiFi network. The speed sensor is connected to the data collector. Both the data collector and the temperature acquisition device communicate with the host computer via a WiFi network.

[0009] The data collector includes a first main control chip, a memory, a first communication module, a third communication module, a first power supply module and a switch input interface. The memory, the first communication module, the third communication module and the switch input interface are all connected to the first main control chip. The first power supply module supplies power to the memory, the first communication module, the third communication module and the first main control chip.

[0010] The switch input interface is connected to the speed sensor;

[0011] The temperature acquisition device includes a second main control chip, a second communication module, a fourth communication module, a second power supply module, a first constant current source, a second constant current source, a multi-channel analog switch, a current detection unit, a 5-channel temperature acquisition unit and an AD chip. The second communication module, the fourth communication module, the first constant current source, the second constant current source and the AD chip are all connected to the second main control chip;

[0012] The first constant current source and the second constant current source are also connected to the multi-way analog switch, the multi-way analog switch is connected to the current detection unit, and the current detection unit is connected to the AD chip;

[0013] Each of the five temperature acquisition units includes a sensor interface, a temperature signal amplifier, and an indicator light circuit. For any temperature acquisition unit, the sensor interface is connected to the input interface of the temperature signal amplifier, the output interface of the temperature signal amplifier is connected to the AD chip, and the output interface of the temperature signal amplifier is also connected to the indicator light circuit.

[0014] The first constant current source and the second constant current source provide independent constant current power supply for the five temperature acquisition units respectively; the second power supply module supplies power to the second main control chip, the second communication module, the fourth communication module, the first constant current source, the second constant current source, the multi-channel analog switch, the current detection unit, the five temperature acquisition units and the AD chip;

[0015] The first communication module and the second communication module are both WIFI communication modules, and the third communication module and the fourth communication module are both LORA communication modules; the third communication module and the fourth communication module establish a LORA communication link, the first communication module and the second communication module communicate with each other, and the first communication module and the second communication module also communicate with the host computer respectively.

[0016] Preferably, in the data acquisition, the model of the first main control chip is STM32H743VIT6; the model of the memory is W25Q256JV; the model of the first communication module is USR-WIFI232; the model of the third communication module is SX1276; the model of the speed sensor is ROLS-5PW laser speed sensor;

[0017] The first power supply module includes a 12V power supply interface, a 5V voltage regulator and a 3.3V voltage regulator, the 12V power supply interface is connected to the 5V voltage regulator, and the 5V voltage regulator is connected to the 3.3V voltage regulator;

[0018] The model of the 5V voltage regulator is LM7805; the model of the 3.3V voltage regulator is AMS1117-3.3.

[0019] Preferably, in the temperature acquisition device, the model of the second main control chip is STM32H743VIT6, the model of the second communication module is USR-WIFI232; the model of the fourth communication module is SX1276; the model of the first constant current source and the second constant current source are both AD5724R; the model of the multi-way analog switch is ADG2128; the model of the AD chip is ADS124S08.

[0020] Preferably, the current detection unit includes a detection resistor RX, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a capacitor C1, a capacitor C2, a capacitor C3, a resistor RG, an amplifier IC4, an amplifier IC5, a resistor R6 and a resistor R7, pin 1 of the detection resistor RX is connected to an output terminal Y0 of the multi-way analog switch, and pin 2 is connected to the ground line through R2 and the resistor R3 connected in series, pin 1 and pin 2 of the detection resistor RX are further connected to the positive input terminal IN+ and the negative input terminal IN- of the amplifier IC4 through the resistor R4 and the resistor R5 respectively, the positive input terminal IN+ and the negative input terminal IN- of the amplifier IC4 are connected to the ground line through the capacitor C1 and the capacitor C3 respectively, and the capacitor C2 is connected between the positive input terminal IN+ and the negative input terminal IN- of the amplifier IC4;

[0021] The resistor RG is the amplification gain resistor of the amplifier IC4;

[0022] The positive input terminal of amplifier IC5 is connected to the voltage divider circuit composed of resistors R6 and R7, and the negative input terminal is connected to the output terminal of amplifier IC5. The output terminal of amplifier IC5 is connected to the REF terminal of amplifier IC4; the output terminal of amplifier IC4 is connected to an AD input interface of the AD chip.

[0023] Preferably, the model of the amplifier IC4 is AD8422, and the model of the amplifier IC5 is OP1117.

[0024] Preferably, in any temperature acquisition unit, the sensor interface is connected to an external 4-wire PT100 temperature sensor; the model of the temperature signal amplifier is AD8422; the indicator light circuit includes a comparator and an LED lamp, the positive input end of the comparator is connected to the output end of the temperature signal amplifier, the negative input end is connected to the reference voltage, and the output end drives the LED lamp;

[0025] The model of the comparator is LM358.

[0026] Preferably, the second power supply module includes a charging interface, a lithium battery management chip, a lithium battery pack, a boost module and a voltage regulator chip, the charging interface and the lithium battery pack are connected to the lithium battery management chip, the lithium battery management chip outputs a 4.2V power supply, the input end of the boost module is connected to the 4.2V power supply, the output end outputs a 5V power supply, the input end of the voltage regulator chip is connected to the 5V power supply, and the output end outputs a 3.3V power supply;

[0027] The model of the lithium battery management chip is TP4056, the model of the boost module is MC1900, and the model of the voltage regulator chip is AMS1117-3.3.

[0028] The calibration system of a microplate incubator based on Internet of Things communication described in the present invention solves the technical problem of real-time and accurate collection of multi-point temperature data and speed data of a microplate incubator through Internet of Things technology. The present invention adopts a 4-wire PT100 sensor combined with a design of independent power supplies provided by dual constant current sources to eliminate the influence of lead resistance. The temperature measurement accuracy can reach ±0.1°C, and 5 independent temperature acquisition channels support multi-point synchronous monitoring, which can achieve a comprehensive evaluation of the temperature uniformity of the microplate incubator. The laser speed sensor adopts non-contact measurement with an accuracy of ±0.1%, avoiding mechanical interference. Parameter setting, data recording and alarm management are realized through the host computer, reducing manual intervention and improving calibration efficiency. The dual communication channel complementary design of WIFI (high-speed channel) and LORA (low-power channel) is adopted to adapt to the complex electromagnetic environment of the laboratory and ensure data transmission stability. The data collector and temperature acquisition device are independently designed and can be flexibly deployed or expanded in function. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a system architecture diagram of the present invention;

[0030] Figure 2 It is a schematic block diagram of the data collector of the present invention;

[0031] Figure 3 is a schematic block diagram of the first power module of the present invention;

[0032] Figure 4 It is a block diagram of the principle diagram of the temperature acquisition device of the present invention;

[0033] Figure 5 is a schematic block diagram of the second power module of the present invention;

[0034] Figure 6 It is a schematic diagram of the first constant current source, the second constant current source, the multi-channel analog switch and the current detection unit of the present invention;

[0035] Figure 7 This is a schematic diagram of the first temperature acquisition unit of the present invention;

[0036] Figure 8 It is a schematic diagram of the four-wire PT100 temperature sensor of the present invention and its corresponding interfaces. DETAILED DESCRIPTION

[0037] Depend on Figures 1-8 The microplate incubator calibration system shown here, based on IoT communication, includes a host computer, a data collector, a speed sensor, and a temperature acquisition device. The temperature acquisition device and the data collector communicate via a LORA network or a WIFI network. The speed sensor is connected to the data collector. Both the data collector and the temperature acquisition device communicate with the host computer via a WIFI network.

[0038] In this embodiment, there are two communication channels between the temperature acquisition device and the data collector: WIFI communication (high speed) or LORA communication (low power consumption). When the data collector cannot establish a communication link with the temperature acquisition device, the temperature acquisition device can also directly establish a link with the host computer through WIFI communication.

[0039] The data collector and the host computer are linked via WIFI communication. The data collector and the speed sensor are deployed together and can be directly deployed on the fixed tripod of the speed sensor.

[0040] The data collector includes a first main control chip, a memory, a first communication module, a third communication module, a first power supply module and a switch input interface. The memory, the first communication module, the third communication module and the switch input interface are all connected to the first main control chip. The first power supply module supplies power to the memory, the first communication module, the third communication module and the first main control chip.

[0041] In the data acquisition, the model of the first main control chip is STM32H743VIT6; the model of the memory is W25Q256JV; the model of the first communication module is USR-WIFI232; the model of the third communication module is SX1276; the model of the speed sensor is ROLS-5PW laser speed sensor;

[0042] The first power supply module includes a 12V power supply interface, a 5V voltage regulator and a 3.3V voltage regulator, the 12V power supply interface is connected to the 5V voltage regulator, and the 5V voltage regulator is connected to the 3.3V voltage regulator;

[0043] The model of the 5V voltage regulator is LM7805; the model of the 3.3V voltage regulator is AMS1117-3.3.

[0044] The switch input interface is connected to the speed sensor;

[0045] In this embodiment, the rotation speed sensor adopts the ROLS-5PW type non-contact laser sensor. When in use, the laser sensor can be placed on a tripod, and the laser probe can be aimed at the device to be tested for measurement. The measurement is simple and convenient. Its output signal is a TTL signal, which is sent to the first main control chip through the switch input interface.

[0046] The first main control chip is responsible for receiving various temperature data and self-test data transmitted by the temperature acquisition device and uploading them to the host computer. At the same time, the first main control chip is also responsible for real-time acquisition of the TTL signal of the speed sensor, converting the pulse signal into a speed through a counter counting method, and sending it to the host computer.

[0047] The memory is responsible for caching the historical data of each temperature data channel and the historical speed data.

[0048] The first communication module uses WIFI communication and is responsible for establishing a link with the host computer or the temperature acquisition device. The third communication module uses LORA communication and is only responsible for establishing a link with the temperature acquisition device.

[0049] The temperature acquisition device includes a second main control chip, a second communication module, a fourth communication module, a second power supply module, a first constant current source, a second constant current source, a multi-channel analog switch, a current detection unit, a 5-channel temperature acquisition unit and an AD chip. The second communication module, the fourth communication module, the first constant current source, the second constant current source and the AD chip are all connected to the second main control chip;

[0050] The first communication module and the second communication module are both WIFI communication modules, and the third communication module and the fourth communication module are both LORA communication modules; the third communication module and the fourth communication module establish a LORA communication link, the first communication module and the second communication module communicate with each other, and the first communication module and the second communication module also communicate with the host computer respectively.

[0051] In the temperature acquisition device, the model of the second main control chip is STM32H743VIT6, the model of the second communication module is USR-WIFI232; the model of the fourth communication module is SX1276; the model of the first constant current source and the second constant current source are both AD5724R; the model of the multi-way analog switch is ADG2128; and the model of the AD chip is ADS124S08.

[0052] The first constant current source and the second constant current source are also connected to the multi-way analog switch, the multi-way analog switch is connected to the current detection unit, and the current detection unit is connected to the AD chip;

[0053] The first constant current source and the second constant current source can both output 4 constant current power supplies. In this embodiment, the 4 constant current power supplies of the first constant current source and the 1 constant current power supply of the second constant current source are selected for use. Figure 6 As shown, the first constant current source is constant current source IC1, and the second constant current source is constant current source IC2. Constant current source IC1 and constant current source IC2 are connected to the second main control chip through the SPI interface in a cascade manner. The specific connection interfaces include MOSI, SCK, IO1-AD5724, IO2-AD5724 and MISO. The SDO port of constant current source IC1 is connected to the SDIN port of constant current source IC2.

[0054] The output of the constant current source IC1 includes a constant current source V1, a constant current source V2, a constant current source V3 and a constant current source V4; the output of the constant current source IC2 includes a constant current source V5.

[0055] Constant current source V1, constant current source V2, constant current source V3, constant current source V4 and constant current source V5 are respectively used to independently power the five temperature acquisition units to reduce mutual interference between the signals.

[0056] The current detection unit includes a detection resistor RX, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a capacitor C1, a capacitor C2, a capacitor C3, a resistor RG, an amplifier IC4, an amplifier IC5, a resistor R6 and a resistor R7, a pin 1 of the detection resistor RX is connected to an output terminal Y0 of the multi-way analog switch, and a pin 2 is connected to the ground line through R2 and the resistor R3 connected in series, a pin 1 and a pin 2 of the detection resistor RX are further connected to the positive input terminal IN+ and the negative input terminal IN- of the amplifier IC4 through the resistor R4 and the resistor R5 respectively, the positive input terminal IN+ and the negative input terminal IN- of the amplifier IC4 are connected to the ground line through the capacitor C1 and the capacitor C3 respectively, and the capacitor C2 is connected between the positive input terminal IN+ and the negative input terminal IN- of the amplifier IC4;

[0057] The resistor RG is the amplification gain resistor of the amplifier IC4;

[0058] The positive input terminal of amplifier IC5 is connected to the voltage divider circuit composed of resistors R6 and R7, and the negative input terminal is connected to the output terminal of amplifier IC5. The output terminal of amplifier IC5 is connected to the REF terminal of amplifier IC4; the output terminal of amplifier IC4 is connected to an AD input interface of the AD chip.

[0059] In this embodiment, in order to ensure the acquisition accuracy of each temperature data, the constant current source V1, constant current source V2, constant current source V3, constant current source V4 and constant current source V5 are respectively detected before acquisition to ensure that the outputs of the 5 constant current sources are consistent. The detection circuit is a current detection unit. In order to save port resources, this embodiment uses a multi-channel analog switch to switch the constant current source V1, constant current source V2, constant current source V3, constant current source V4 and constant current source V5. Figure 6 As shown, the multi-way analog switch is an analog switch IC3. The input ends of the analog switch IC3 include X0 to X111, and the output ends include Y0 to Y7. The constant current sources V1, V2, V3, V4 and V5 are input into X0 to X4 respectively, and are switched to Y0 respectively through the switching of the analog switch IC3.

[0060] The resistor RX is a current measuring resistor, and the resistors R2 and R3 are matching resistors. The two ends of the resistor RX are input into the amplifier IC4, thereby realizing the collection and amplification of the current at the Y0 end. By polling, the constant current sources V1, V2, V3, V4 and V5 are respectively switched to the Y0 end to realize the current collection and amplification of each constant current source.

[0061] Amplifier IC5 provides reference voltage for amplifier IC4, and the final output of amplifier IC4 enters the AD chip.

[0062] The RESET terminal, A2 terminal, A1 terminal, A0 terminal, SCL terminal, and SDA terminal of the analog switch IC3 are respectively connected to different IO ports of the second control chip, and the second control chip controls the analog switch IC3 to switch.

[0063] The model of the amplifier IC4 is AD8422, and the model of the amplifier IC5 is OP1117.

[0064] Each of the five temperature acquisition units includes a sensor interface, a temperature signal amplifier, and an indicator light circuit. For any temperature acquisition unit, the sensor interface is connected to the input interface of the temperature signal amplifier, the output interface of the temperature signal amplifier is connected to the AD chip, and the output interface of the temperature signal amplifier is also connected to the indicator light circuit.

[0065] In any temperature acquisition unit, the sensor interface is connected to an external 4-wire PT100 temperature sensor; the model of the temperature signal amplifier is AD8422; the indicator light circuit includes a comparator and an LED light, the positive input end of the comparator is connected to the output end of the temperature signal amplifier, the negative input end is connected to the reference voltage, and the output end drives the LED light;

[0066] The model of the comparator is LM358.

[0067] like Figure 7 and Figure 8 As shown, the temperature sensors are sensor RT1, sensor RT2, sensor RT3, sensor RT4, and sensor RT5. These five temperature sensors are deployed on the microplate of the microplate incubator. The specific deployment positions can be determined according to product requirements.

[0068] Sensor RT1, sensor RT2, sensor RT3, sensor RT4, and sensor RT5 are connected to the five-way temperature acquisition unit through five sensor interfaces, namely interface J1, interface J2, interface J3, interface J4, and interface J5.

[0069] The first temperature acquisition unit includes a first sensor interface, a first amplifier and a first indicator light circuit; the second temperature acquisition unit includes a second sensor interface, a second amplifier and a second indicator light circuit; the third temperature acquisition unit includes a third sensor interface, a third amplifier and a third indicator light circuit; the fourth temperature acquisition unit includes a fourth sensor interface, a fourth amplifier and a fourth indicator light circuit; and the fifth temperature acquisition unit includes a fifth sensor interface, a fifth amplifier and a fifth indicator light circuit.

[0070] Taking the first temperature acquisition unit as an example, the first sensor interface is the interface J1, the first amplifier is the amplifier IC6, and the first indicator light circuit is the LED lamp driving circuit composed of the comparator IC8 and the LED lamp D1.

[0071] The output of sensor RT1 includes FORCE+ port, RTDIN+ port, FORCE- port, and RTDIN- port. FORCE+ port, RTDIN+ port, FORCE- port, and RTDIN- port are respectively connected to pins 4, 3, 2, and 1 of interface J1. Pin 4 of interface J1 is connected to constant current source V1, pins 3 and 2 are respectively connected to the positive input terminal IN+ and negative input terminal IN- of amplifier IC6 through resistors R9 and R10, and pin 1 is connected to the ground.

[0072] Sensor RT1 is independently powered by a constant current source V1, and its output signals (RTDIN+ and RTDI N-) are connected to amplifier IC6. Amplifier IC6 amplifies the temperature signal collected by sensor RT1 and inputs it into an AD conversion channel of the AD chip.

[0073] Amplifier IC7 is used to provide a reference voltage for amplifier IC6.

[0074] At the use site, since there are many sensor collection channels, it is very likely that a sensor is not installed properly during the sensor installation process. In this embodiment, an indicator light circuit is used to indicate the output status of each sensor channel.

[0075] The positive input of comparator IC8 is connected to the output of amplifier IC6. When there is a voltage output at the output of amplifier IC6 and it exceeds the voltage divided by resistors R13 and R14, the output of sensor RT1 is judged to be normal. At this time, the comparator will drive indicator light D1 to light up through resistor R19. Otherwise, indicator light D1 will not light up.

[0076] The circuit principles of the second temperature acquisition unit, the third temperature acquisition unit, the fourth temperature acquisition unit, and the fifth temperature acquisition unit are the same as those of the first temperature acquisition unit, but the second temperature acquisition unit, the third temperature acquisition unit, the fourth temperature acquisition unit, and the fifth temperature acquisition unit are independently powered by constant current source V2, constant current source V3, constant current source V4, and constant current source V5, respectively. Figure 8 shown.

[0077] The first constant current source and the second constant current source provide independent constant current power supply for the five temperature acquisition units respectively; the second power supply module supplies power to the second main control chip, the second communication module, the fourth communication module, the first constant current source, the second constant current source, the multi-channel analog switch, the current detection unit, the five temperature acquisition units and the AD chip;

[0078] The second power supply module includes a charging interface, a lithium battery management chip, a lithium battery pack, a boost module and a voltage regulator chip. The charging interface and the lithium battery pack are connected to the lithium battery management chip. The lithium battery management chip outputs a 4.2V power supply. The input end of the boost module is connected to the 4.2V power supply and the output end outputs a 5V power supply. The input end of the voltage regulator chip is connected to the 5V power supply and the output end outputs a 3.3V power supply.

[0079] The model of the lithium battery management chip is TP4056, the model of the boost module is MC1900, and the model of the voltage regulator chip is AMS1117-3.3.

[0080] The following is a working example of the present invention:

[0081] S1: After the system is initialized and each device is powered on, the host computer starts and runs the calibration software to complete parameter configuration (such as some preset settings, sampling intervals, alarm thresholds, etc.).

[0082] The temperature acquisition device and the data collector are powered on and started. After the self-test is completed, an attempt is made to establish a communication link via Wi-Fi first.

[0083] If the WIFI signal is unstable, the temperature acquisition device and the data collector will automatically switch to LOR A communication; if communication with the data collector is impossible, the temperature acquisition device will try to establish a WIFI connection directly with the host computer.

[0084] S2: Temperature signal acquisition and processing process includes:

[0085] The second main control chip controls the multi-channel analog switch, polling and switching the 5-channel constant current source V1-constant current source V5, and detecting the voltage of the constant current source V1-constant current source V5 one by one. If there is a fault, it will immediately alarm the host computer or data collector;

[0086] After passing the constant current source test, the analog signals output by each PT100 sensor are amplified by the AD8422 amplifier and then sent to the AD chip ADS124S08 for digital conversion in real time. The AD chip uses multiplexing + internal automatic switching sampling, and all channels are sampled channel by channel. However, the conversion time difference is about tens of milliseconds, which is sufficient to achieve synchronization for temperature detection.

[0087] The converted digital temperature data is packaged by the second main control chip and sent to the data collector via WIFI or LORA or directly to the host computer.

[0088] At the same time, the indicator light circuit (composed of LM358) provides real-time indication of the working status of each temperature acquisition unit, making it easy for humans to quickly identify whether the sensor is installed abnormally or damaged.

[0089] S3: The speed data acquisition and processing process includes: the laser speed sensor ROLS-5PW non-contact detects the speed of the fan blades in the incubator and outputs a TTL pulse signal; the pulse signal is connected to the switch input interface of the data collector, counted and processed by the first main control chip STM32H743VIT6, and converted into the actual speed value.

[0090] S4: The data collector caches the collected temperature data and speed data in the W25Q256JV memory to ensure breakpoint resumability; the data collector transmits the data to the host computer via the USR-WIFI232 module in WIFI mode for centralized management.

[0091] S5: The host computer receives all data and displays the five temperatures and current speed in real time. It can further process the five temperatures and current speed, such as automatically saving all historical data and supporting export reports.

[0092] The calibration system of a microplate incubator based on Internet of Things communication described in the present invention solves the technical problem of real-time and accurate collection of multi-point temperature data and speed data of a microplate incubator through Internet of Things technology. The present invention adopts a 4-wire PT100 sensor combined with a design of independent power supplies provided by dual constant current sources to eliminate the influence of lead resistance. The temperature measurement accuracy can reach ±0.1°C, and 5 independent temperature acquisition channels support multi-point synchronous monitoring, which can achieve a comprehensive evaluation of the temperature uniformity of the microplate incubator. The laser speed sensor adopts non-contact measurement with an accuracy of ±0.1%, avoiding mechanical interference. Parameter setting, data recording and alarm management are realized through the host computer, reducing manual intervention and improving calibration efficiency. The dual communication channel complementary design of WIFI (high-speed channel) and LORA (low-power channel) is adopted to adapt to the complex electromagnetic environment of the laboratory and ensure data transmission stability. The data collector and temperature acquisition device are independently designed and can be flexibly deployed or expanded in function.

Claims

1. A calibration system for a microplate incubator based on Internet of Things communication, characterized by: It includes a host computer, a data collector, a speed sensor and a temperature acquisition device. The temperature acquisition device and the data collector communicate through a LORA network or a WIFI network. The speed sensor is connected to the data collector. Both the data collector and the temperature acquisition device communicate with the host computer through a WIFI network. The data collector includes a first main control chip, a memory, a first communication module, a third communication module, a first power supply module and a switch input interface. The memory, the first communication module, the third communication module and the switch input interface are all connected to the first main control chip. The first power supply module supplies power to the memory, the first communication module, the third communication module and the first main control chip. The switch input interface is connected to the speed sensor; The temperature acquisition device includes a second main control chip, a second communication module, a fourth communication module, a second power supply module, a first constant current source, a second constant current source, a multi-channel analog switch, a current detection unit, a 5-channel temperature acquisition unit and an AD chip. The second communication module, the fourth communication module, the first constant current source, the second constant current source and the AD chip are all connected to the second main control chip; The first constant current source and the second constant current source are also connected to the multi-way analog switch, the multi-way analog switch is connected to the current detection unit, and the current detection unit is connected to the AD chip; Each of the five temperature acquisition units includes a sensor interface, a temperature signal amplifier, and an indicator light circuit. For any temperature acquisition unit, the sensor interface is connected to the input interface of the temperature signal amplifier, the output interface of the temperature signal amplifier is connected to the AD chip, and the output interface of the temperature signal amplifier is also connected to the indicator light circuit. The first constant current source and the second constant current source provide independent constant current power supply for the five temperature acquisition units respectively; the second power supply module supplies power to the second main control chip, the second communication module, the fourth communication module, the first constant current source, the second constant current source, the multi-channel analog switch, the current detection unit, the five temperature acquisition units and the AD chip; The first communication module and the second communication module are both WIFI communication modules, and the third communication module and the fourth communication module are both LORA communication modules; the third communication module and the fourth communication module establish a LORA communication link, the first communication module and the second communication module communicate with each other, and the first communication module and the second communication module also communicate with the host computer respectively.

2. The microplate incubator calibration system based on Internet of Things communication according to claim 1, characterized in that: In the data acquisition, the model of the first main control chip is STM32H743VIT6; the model of the memory is W25Q256JV; the model of the first communication module is USR-WIFI232; the model of the third communication module is SX1276; the model of the speed sensor is ROLS-5PW laser speed sensor; The first power supply module includes a 12V power supply interface, a 5V voltage regulator and a 3.3V voltage regulator, the 12V power supply interface is connected to the 5V voltage regulator, and the 5V voltage regulator is connected to the 3.3V voltage regulator; The model of the 5V voltage regulator is LM7805; the model of the 3.3V voltage regulator is AMS1117-3.

3.

3. The microplate incubator calibration system based on Internet of Things communication according to claim 1, characterized in that: In the temperature acquisition device, the model of the second main control chip is STM32H743VIT6, the model of the second communication module is USR-WIFI232; the model of the fourth communication module is SX1276; the model of the first constant current source and the second constant current source are both AD5724R; the model of the multi-way analog switch is ADG2128; and the model of the AD chip is ADS124S08.

4. The microplate incubator calibration system based on Internet of Things communication according to claim 1, characterized in that: The current detection unit includes a detection resistor RX, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a capacitor C1, a capacitor C2, a capacitor C3, a resistor RG, an amplifier IC4, an amplifier IC5, a resistor R6 and a resistor R7, a pin 1 of the detection resistor RX is connected to an output terminal Y0 of the multi-way analog switch, and a pin 2 is connected to the ground line through R2 and the resistor R3 connected in series, a pin 1 and a pin 2 of the detection resistor RX are further connected to the positive input terminal IN+ and the negative input terminal IN- of the amplifier IC4 through the resistor R4 and the resistor R5 respectively, the positive input terminal IN+ and the negative input terminal IN- of the amplifier IC4 are connected to the ground line through the capacitor C1 and the capacitor C3 respectively, and the capacitor C2 is connected between the positive input terminal IN+ and the negative input terminal IN- of the amplifier IC4; The resistor RG is the amplification gain resistor of the amplifier IC4; The positive input terminal of amplifier IC5 is connected to the voltage divider circuit composed of resistors R6 and R7, and the negative input terminal is connected to the output terminal of amplifier IC5. The output terminal of amplifier IC5 is connected to the REF terminal of amplifier IC4; the output terminal of amplifier IC4 is connected to an AD input interface of the AD chip.

5. The microplate incubator calibration system based on Internet of Things communication according to claim 4, characterized in that: The model of the amplifier IC4 is AD8422, and the model of the amplifier IC5 is OP1117.

6. The microplate incubator calibration system based on Internet of Things communication according to claim 1, characterized in that: In any temperature acquisition unit, the sensor interface is connected to an external 4-wire PT100 temperature sensor; the model of the temperature signal amplifier is AD8422; the indicator light circuit includes a comparator and an LED light, the positive input end of the comparator is connected to the output end of the temperature signal amplifier, the negative input end is connected to the reference voltage, and the output end drives the LED light; The model of the comparator is LM358.

7. The microplate incubator calibration system based on Internet of Things communication according to claim 1, characterized in that: The second power supply module includes a charging interface, a lithium battery management chip, a lithium battery pack, a boost module and a voltage regulator chip. The charging interface and the lithium battery pack are connected to the lithium battery management chip. The lithium battery management chip outputs a 4.2V power supply. The input end of the boost module is connected to the 4.2V power supply and the output end outputs a 5V power supply. The input end of the voltage regulator chip is connected to the 5V power supply and the output end outputs a 3.3V power supply. The model of the lithium battery management chip is TP4056, the model of the boost module is MC1900, and the model of the voltage regulator chip is AMS1117-3.3.

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