CN215449265U

CN215449265U - Thing networking soil and air temperature and humidity detection device based on loRa

Info

Publication number: CN215449265U
Application number: CN202120562668.0U
Authority: CN
Inventors: 唐莉; 胡树林; 侯冬晴
Original assignee: Jishou University
Current assignee: Jishou University
Priority date: 2021-03-19
Filing date: 2021-03-19
Publication date: 2022-01-07
Anticipated expiration: 2031-03-19

Abstract

The utility model relates to a LoRa-based Internet of things soil and air temperature and humidity detection device, which can be used for simultaneously detecting the temperature and humidity of soil and air, and completing the functions which can be completed by two devices originally by one detection device, so that the cost is saved and the carrying is convenient. And can upload humiture data to the server through loRa wireless module, insert the internet promptly. The detection device comprises a soil temperature and humidity collector, an RS485 converter, a reset circuit, a crystal oscillator circuit, a key module, a buzzer, a central processing unit, an air temperature and humidity sensor, a battery module, a LoRa wireless module and the like. The soil temperature and humidity collector samples the temperature and humidity physical quantity of soil and converts the temperature and humidity physical quantity into digital quantity which is transmitted to the central processing unit through the RS485 converter, and the air temperature and humidity sensor samples the temperature and humidity physical quantity in air and converts the temperature and humidity physical quantity into digital quantity which is transmitted to the central processing unit through the I2C. And the central processing unit sends the received soil temperature, humidity and air temperature and humidity to the server through the LoRa wireless module. The battery module provides power for related modules in the detection device.

Description

Thing networking soil and air temperature and humidity detection device based on loRa

Technical Field

The utility model relates to wireless data transmission of soil temperature, humidity, air temperature and humidity and LoRa, belonging to the field of electronic technology and wireless communication.

Background

The temperature and humidity parameters play a vital role in the places of people's life, industrial production, scientific research, biology, medicine, metallurgy, machinery, food, chemical industry, laboratories and the like.

The currently known soil temperature and humidity measuring instrument can only detect the temperature and the humidity of soil, and the air temperature and humidity measuring instrument can only detect the temperature and the humidity of air. The soil temperature and humidity measuring instrument is composed of a soil temperature and humidity sensor, an RS485 interface, a central processing unit, a key module, a display screen, a power supply and other modules. Soil temperature and humidity sensor sampling soil temperature and humidity parameter conversion is digital quantity and sends central processing unit to through the 485 interface, and central processing unit sends the display screen to accomplish the humiture after taking warm and humid data and shows, and the button module provides setting and control function for the measuring apparatu. The air temperature and humidity measuring instrument is composed of an air temperature and humidity sensor, an I2C interface, a central processing unit, a key module, a display screen, a power supply and other modules. The air temperature and humidity sensor samples temperature and humidity in the air and converts the temperature and humidity quantity into temperature and humidity data, the temperature and humidity data are transmitted to the central processing unit through the I2C interface, the temperature and humidity data are transmitted to the display screen by the central processing unit to be displayed, and the key module provides setting and control functions.

The LoRa is one of LPWAN communication technologies, and is an ultra-long-distance wireless transmission scheme based on spread spectrum technology adopted and popularized by Semtech corporation in the united states. The proposal changes the compromise mode of transmission distance and power consumption, provides a system which can realize long distance, long battery life and large capacity for users, and further expands the transmission network. Currently, the LoRa mainly operates in free frequency bands worldwide, including frequency bands of 470, 868, 915 MHz and the like. The LoRa technology has the characteristics of long distance, low power consumption, multiple nodes and low cost. Under ideal environment, the LoRa wireless transmission distance can reach 10+ kilometers.

The prior soil and air temperature and humidity measuring instrument has the following obvious defects.

(1) The soil temperature and humidity measuring instrument can only measure the temperature and humidity of soil, and the air temperature and humidity measuring instrument can only measure the temperature and humidity of air, but cannot simultaneously measure the temperature and humidity of the soil and the air.

(2) The soil temperature and humidity measuring instrument and the air temperature and humidity measuring instrument are required for measuring soil and air temperature and humidity, and are high in cost and inconvenient to carry.

(3) The soil and air temperature and humidity measuring instrument cannot transmit temperature and humidity data to the server or can only transmit the temperature and humidity data to the server through the traditional wireless technology, and the application requirements of a new scene cannot be met.

(4) The soil and air temperature and humidity measuring instrument can only display the temperature and humidity data at that time, and cannot draw a temperature and humidity change curve.

The device for detecting the temperature and humidity of soil and air in the internet of things based on LoRa has the functions of two existing temperature and humidity measuring instruments and can overcome the four defects.

Disclosure of Invention

The utility model provides a thing networking soil and air temperature and humidity detection device based on loRa comprises parts such as soil temperature and humidity collector, RS485 converter, reset circuit, crystal oscillator circuit, button module, bee calling organ, central processing unit, air temperature and humidity sensor, battery module, loRa wireless module.

The soil temperature and humidity collector inserts a metal probe for measuring the temperature and the humidity of the soil into the soil to be measured, the metal probe samples physical quantity of the temperature and the humidity of the soil and converts the physical quantity into a weak electric signal, and then the weak electric signal is converted into temperature and humidity digital quantity through a conditioning circuit and sent to the central processing unit through the RS485 converter.

And the RS485 converter realizes the mutual conversion of the RS485 differential signal data and the TTL level data. The soil temperature and humidity collector sends temperature and humidity data through the RS485 differential signal, a serial port of the central processing unit can only receive data of TTL level, and the level conversion is completed by the RS485 converter.

The reset circuit provides a reset signal for the central processing unit, and the reset key provides 2.5mS low level resettable central processing unit after being pressed.

The crystal oscillator circuit provides a working clock signal for the central processing unit, and the oscillation frequency of the crystal oscillator of the soil and air temperature and humidity detection device of the Internet of things is 8 MHz.

And the key module can set working parameters of the detection device through keys and restore the functions of the detection device such as default parameters and the like.

And the buzzer buzzes 3 times after the detection device successfully accesses the network, the length of each buzzing is 200mS, and the period is 1S. Beeping sounds occur at low, ultra-high, ultra-low temperatures of the battery and other faults.

And the central processing unit is a control core of the soil and air temperature and humidity detection device of the Internet of things. The soil temperature and humidity data and the air temperature and humidity data are received from the serial port through I2C, are packaged according to the data format in the LoRa WAN protocol, are transmitted to the server through the LoRa wireless module, and meanwhile, commands from the server can be received through the LoRa wireless module. And the management of various peripheral devices such as a key module, a buzzer, a LoRa wireless module, a battery module and the like is completed. And analyzing the LoRa WAN protocol in the LoRa wireless communication process. And starting a watchdog timer function, and restarting the detection device when the system is deadlocked.

The air temperature and humidity sensor samples temperature and humidity physical quantities in air, converts the temperature and humidity physical quantities into electric signals, converts the electric signals into digital quantities through an analog-to-digital converter, and then sends the digital quantities to the central processing unit through an I2C interface.

The detection device of the battery module adopts 2 3.7V 18650 batteries to supply power in series, the voltage after the series connection is 7.4V, and the battery module can be repeatedly charged and recycled. A 7.4V power supply is provided for the RS485 converter; convert into 3.3V's voltage through DC TO DC module, provide 3.3V's power for central processing unit, bee calling organ, air temperature and humidity sensor, loRa wireless module.

And the LoRa wireless module is used for completing the modulation and demodulation of signals in the wireless communication process and adopting an unauthorized frequency band of 470 MHz. This detection device sends humiture data and receives control command from the server through loRa wireless module to the server, promptly through loRa wireless module with detection device access to internet to soil and air humiture are looked over to computer, cell-phone are long-range, and control detection device.

Drawings

The utility model is further illustrated with reference to the following figures and examples.

Fig. 1 is a block diagram of the soil and air temperature and humidity detection device based on LoRa for the internet of things.

In fig. 1: 1. the soil temperature and humidity collector comprises a soil temperature and humidity collector, 2. an RS485 converter, 3. a reset circuit, 4. a crystal oscillator circuit, 5. a key module, 6. a buzzer, 7. a central processing unit, 8. an air temperature and humidity sensor, 9. a battery module and 10. a LoRa wireless module.

Detailed Description

The soil temperature and humidity collector 1 is characterized in that the soil temperature and humidity collector 1 samples temperature and humidity physical quantities through a metal probe inserted into soil and converts the temperature and humidity physical quantities into weak electric signals, then the temperature and humidity digital quantities are converted through a conditioning circuit and sent to an RS485 converter 2.

RS485 converter 2, RS485 converter 2 IC adopt MAX485, and RS485 converter 2 receives soil temperature and humidity collector 1 and sends humiture data, then sends data transfer to central processing unit 7 through the serial ports.

The reset circuit 3, the reset circuit 3 adopts the key reset mode. When the key is pressed, a low level of 2.5mS is provided for the central processing unit 7, and the central processing unit 7 is restarted.

The crystal oscillator circuit 4 adopts a passive crystal oscillator, and the frequency of the crystal oscillator is 8 MHz. The crystal oscillator circuit 4 provides an operating clock for the cpu 7. The central processor 7 multiplies the frequency by the PLL to an operating frequency of 72 MHz.

And the key module 5 adopts a 4-key scheme, sets working parameters of the detection device, and restores default parameters of the detection device by long keys.

The buzzer 6 buzzes 3 times after the detection device successfully accesses the network; beeping when the battery module 9 voltage is too low; when the temperature and humidity of the soil and the air exceed the set threshold value, a buzzer is sounded.

And the central processing unit 7 is a control core of the soil and air temperature and humidity detection device based on the LoRa Internet of things. Receiving soil temperature and humidity data from the RS485 converter 2 and receiving air humidity data from the air temperature and humidity sensor 8, packaging and uploading the data to a server through the LoRa wireless module 10; commands from the server are received through the LoRa wireless module 10. And the management function of various peripheral devices such as the key module 5, the buzzer 6, the LoRa wireless module 10, the battery module 9 and the like is completed.

The air temperature and humidity sensor 8 samples the temperature and humidity physical quantity in the air, converts the temperature and humidity physical quantity into temperature and humidity digital quantity, and sends the temperature and humidity digital quantity to the central processing unit 7 through I2C.

And the battery module 9 is formed by connecting 2 batteries with 3.7V and 18650 in series, and provides a 7.4V power supply for the RS485 converter 2. Through DC TO DC module conversion 3.3V, for bee calling organ 6, central processing unit 7, air temperature and humidity sensor 8, loRa wireless module 10 provide 3.3V's power.

The LoRa wireless module 10, the LoRa wireless module 10 completes the modulation and demodulation functions of the signal in the wireless communication. Adopt 470 MHz's unauthorized frequency channel, this detection device passes through loRa wireless module 10 to server transmission humiture data and receives control command from the server, promptly through loRa wireless module 10 with detection device access internet to soil, air temperature and humidity are looked over to computer, cell-phone are long-range, and control detection device.

Claims

1. The utility model provides a thing networking soil and air temperature and humidity detection device based on loRa, characterized by: this thing networking soil and air temperature and humidity detection device includes:

the soil temperature and humidity collector inserts a metal probe of the collector into soil, and sampled soil temperature and humidity physical quantities are converted into temperature and humidity data through a conditioning circuit and then transmitted to an RS485 converter through an RS485 line;

the RS485 converter receives temperature and humidity data from the soil temperature and humidity collector through a 485 line and then transmits the temperature and humidity data to the central processing unit through a serial port;

the reset circuit adopts a key reset mode, provides a low level of 2.5mS to the central processing unit after the key is pressed down, and restarts the central processing unit;

the crystal oscillator circuit provides a working clock for the central processing unit, and the oscillation frequency of the crystal oscillator of the detection device is 8 MHz;

the key module is used for setting working parameters of the detection device and recovering default parameters of the detection device;

the buzzer buzzes 3 times after the detection device successfully accesses the network, the length of each buzzing is 200mS, the period is 1S, and the buzzing is given out when the battery voltage is low or the temperature and humidity exceed a set threshold;

the central processing unit is a control core of the soil and air temperature and humidity detection device of the Internet of things, receives data from the soil temperature and humidity collector and the air temperature and humidity sensor, transmits the data to the server through the LoRa wireless module, completes the analysis function of a LoRa WAN protocol in the communication process of the LoRa wireless module, and restarts the detection device under the condition of system deadlock;

the air temperature and humidity sensor samples temperature and humidity physical quantities in air through the temperature and humidity sensor, converts the temperature and humidity physical quantities into temperature and humidity digital quantities through an analog-to-digital converter, and transmits temperature and humidity data to the central processing unit through an I2C interface;

the detection device adopts a 7.4V battery to supply power and provides a 7.4V power supply for the RS485 converter; the DC TO DC is converted into 3.3V TO provide power for the central processing unit, the buzzer, the air temperature and humidity sensor and the LoRa wireless module;

the system comprises a LoRa wireless module, a server, a detection device, a computer and a mobile phone, wherein the LoRa wireless module is used for completing modulation and demodulation of signals in the wireless communication process, the detection device transmits temperature and humidity data to the server through the LoRa wireless module and receives control from the server, namely the detection device is accessed to the Internet through the LoRa wireless module, so that the temperature and humidity data can be remotely checked by the computer and the mobile phone, and the detection device can be controlled.