CN217240941U

CN217240941U - Low-cost wireless state monitoring devices

Info

Publication number: CN217240941U
Application number: CN202122826049.0U
Authority: CN
Inventors: 艾凤明; 王鹤; 梁兴壮; 李征鸿; 王冠; 黄志远; 相毅; 李伟林
Original assignee: Shenyang Aircraft Design and Research Institute Aviation Industry of China AVIC
Current assignee: Shenyang Aircraft Design and Research Institute Aviation Industry of China AVIC
Priority date: 2021-11-17
Filing date: 2021-11-17
Publication date: 2022-08-19
Anticipated expiration: 2031-11-17

Abstract

The application relates to the field of communication, in particular to a low-cost wireless state signal monitoring device which comprises a main node and a plurality of slave nodes; the main node comprises a Bluetooth host; the raspberry pie is connected with the Bluetooth host; wherein, the raspberry pie is respectively connected with the display screen and the pc end; each slave node comprises a sensor data acquisition module and a Bluetooth slave machine, the sensor data acquisition module is connected with the Bluetooth slave machine, the Bluetooth slave machine is connected with the Bluetooth host machine, the sensor data acquisition module is provided with a sensor, the size is small, the cost is low, and the problems of complex structure, high power consumption, large size and high cost of a PC (personal computer) are solved while the data processing function is realized.

Description

Low-cost wireless state monitoring devices

Technical Field

The application relates to the field of communication, in particular to a low-cost wireless state signal monitoring device.

Background

The existing data acquisition system mostly adopts a wired transmission mode, and wired transmission is generally less interfered and has stronger reliability and confidentiality. However, wired transmission has the problems of troublesome wiring, high cost, weak expansibility and the like, and wireless data communication is often a better selection scheme under the environment of some special or severe wiring inconvenience and the like. The wireless technology is adopted, the wireless interface can be used for replacing wired cable connection in a short distance, wireless connection between equipment can be conveniently realized, and the wireless connection device has the characteristics of low cost, low power consumption, high speed, strong anti-interference capability, flexible networking and the like.

The ultra-low cost mini computer represented by the raspberry pie can be used as a server for building various websites and application services and also can be used for learning programming, controlling hardware or daily working based on a Linux system, and has rich and powerful functions. Under the condition of considering cost and portability, the raspberry pie can replace most functions of a PC, and the defects of complex structure, high power consumption, large volume and high cost of the PC are overcome.

SUMMERY OF THE UTILITY MODEL

In order to solve the above problem, the present application provides a low-cost wireless status monitoring device, including: a master node and a plurality of slave nodes;

the main node comprises a Bluetooth host; the raspberry pie is connected with the Bluetooth host; wherein, the raspberry pie is respectively connected with the display screen and the pc end;

each slave node comprises a sensor data acquisition module and a Bluetooth slave, the sensor data acquisition module is connected with the Bluetooth slave, the Bluetooth slave is connected with the Bluetooth host, and the sensor data acquisition module is provided with a sensor.

Preferably, the bluetooth slave node adjusts the transmission power through software programming, and the bluetooth master node sets the device name or the device address through software programming to filter illegal devices.

Preferably, the type of the raspberry pie comprises 4B, the raspberry pie is provided with a Raspbian system and a WIFI module, and the raspberry pie is connected with the Internet through the WIFI module.

Preferably, the display screen comprises an HDMI capacitive display screen, the raspberry group is connected with the HDMI capacitive display screen through an HDMI wire, and the display screen is used for displaying signal changes.

Preferably, the bluetooth slave and the bluetooth master have low power consumption Soc modules, the chip model of the low power consumption Soc module includes nRF52840, and the chip is configured with SPI, I2C and UART interfaces for connecting different sensors.

Preferably, the bluetooth host and the low-power Soc module of the bluetooth slave are communicated by adopting a bluetooth low-power consumption 5.0 protocol.

Preferably, the raspberry pi is connected with the bluetooth host through a USB interface, and data is transmitted through a serial protocol.

Further, the nRF52840 is integrated with a successive approximation ADC, and the calculation formula of the output sampling value is as follows:

wherein V (P) represents the ADC channel positive pole; v (N) represents the ADC channel negative pole; GAIN represents a set GAIN GAIN; REFERENCE denotes a REFERENCE voltage; m denotes that m is 0 if the ADC is configured in a single-ended mode, and m is 1 if the ADC is configured in a differential mode.

The advantages of the present application include: (1) the Bluetooth module of low-power consumption and precision sensor combine to have characteristics small, light in weight, occupation space are few as embedded module, and installation and maintenance are simple, nimble, and the operation is convenient, can cooperate almost any terminal, equipment or switch board, and simultaneously, the Bluetooth module of low-power consumption uses button cell just can run for several months to several years, can be to the long-term monitoring of the part of occasions such as difficult change battery among the monitored control system.

(2) Data between the Bluetooth master and the Bluetooth slave machines are wirelessly transmitted through a Bluetooth low-power-consumption protocol, signal transmission is not required through physical connection, and wired cable transmission is replaced by Bluetooth transmission, so that the Bluetooth master and the Bluetooth slave machines have irreplaceable advantages under the conditions of inconvenient wiring in sealed environment, severe environment and the like.

(3) The raspberry pie has small volume and low cost, and solves the problems of complex structure, high power consumption, large volume and high cost of a PC (personal computer) while realizing the data processing function.

Drawings

Fig. 1 is a schematic view of the main structure of the present invention.

Detailed Description

In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all embodiments of the present application. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application, and should not be construed as limiting the present application. All other embodiments obtained by a person of ordinary skill in the art without any inventive work based on the embodiments in the present application are within the scope of protection of the present application. Embodiments of the present application will be described in detail below with reference to the drawings.

Referring to fig. 1, a low-cost wireless status signal monitoring device based on raspberry pi and bluetooth 5.0 of this embodiment includes: a master node and a plurality of slave nodes;

each slave node comprises a sensor data acquisition module and a Bluetooth slave machine, the sensor data acquisition module is connected with the Bluetooth slave machine, the Bluetooth slave machine is connected with the Bluetooth host machine, and the sensor data acquisition module is provided with a sensor.

The sensor comprises a DS18B20 temperature sensor and an SHT20 humidity temperature sensor, the measurement temperature range of the DS18B20 temperature sensor is-55 ℃ to +125 ℃, the working voltage VCC range is 3.0-5.5V, the temperature value is converted into a number within 750ms at most when the 12-bit resolution is achieved, the temperature can be distinguished to be 0.0625 ℃, and high-precision temperature measurement can be achieved. And a single bus serial interface is adopted to communicate with the nRF52840 chip, and temperature data of the collected signals are sent to the Bluetooth slave node.

The humidity measuring range of the SHT20 wet temperature sensor is 0-100% RH, the measuring precision is +/-3% RH, the temperature measuring range is-40-125 ℃, the measuring precision is +/-0.3 ℃, the working voltage range is 2.1-3.6 VDC, the SHT20 wet temperature sensor is communicated with an nRF52840 chip by adopting a standard I2C protocol, and the humidity and temperature data of collected signals are sent to the Bluetooth slave.

The voltage and other analog signals need to be divided to 0-3.3V by an external voltage division module and then input to an nRF52840 ADC channel port, and the output sampling value calculation formula is as follows:

wherein V (P) represents the ADC channel positive pole; v (N) represents the negative pole of the ADC channel; GAIN represents a set GAIN GAIN; REFERENCE denotes a REFERENCE voltage; m denotes that m is 0 if the ADC is configured in a single-ended mode, and m is l if the ADC is configured in a differential mode.

The plurality of Bluetooth slave machines and the Bluetooth host machine are in wireless connection, and data transmission is carried out by adopting a low-power Bluetooth 5.0 communication protocol.

One Bluetooth host adopts device name filtering and communicates with 8 slave nodes at most simultaneously.

The Bluetooth host is connected with the raspberry pi through a USB, a serial port protocol is adopted to transmit data, and the baud rate is set to 115200.

After the raspberry group receives data, a Python program is written, and the data are read, visualized and stored by referring to pyserial, numpy, pyqtgraph and xlwt databases.

The raspberry pie is connected with the capacitive display screen through an HDMI (high-definition multimedia interface) line, also can be connected with an Internet network through a wireless WIFI (wireless fidelity) module, and accesses to enter a raspberry pie desktop through a remote computer screen VNC to observe changes of monitoring signals.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A low-cost wireless condition monitoring device, comprising: a master node and a plurality of slave nodes;

2. The low-cost wireless condition monitoring device of claim 1, wherein the raspberry pi model comprises 4B with a Raspbian system and a WIFI module, the raspberry pi being connected to the Internet network through the WIFI module.

3. The low-cost wireless condition monitoring device of claim 1, wherein the display screen comprises an HDMI capacitive display screen, the raspberry pi being connected to the HDMI capacitive display screen by an HDMI line.

4. The low-cost wireless state monitoring device as claimed in claim 1, wherein the bluetooth slave and the bluetooth master have a low-power Soc module, the chip model of the low-power Soc module includes nRF52840, and the chip is configured with SPI, I2C and UART interface for connecting different sensors.

5. The low-cost wireless state monitoring device according to claim 4, wherein the Bluetooth host and the low-power Soc module of the Bluetooth slave are communicated by using a Bluetooth low-power 5.0 protocol.

6. The low-cost wireless status monitoring device according to claim 1, wherein the raspberry pi is connected to the bluetooth host through a USB interface, and data is transmitted through a serial protocol.