阅读说明：本技术 一种基于云端通信的光纤光栅传感系统 (Fiber grating sensing system based on cloud communication ) 是由 谭超 万生鹏 徐津 董德壮 熊新中 于 2019-10-29 设计创作，主要内容包括：本发明公开了一种基于云端通信的光纤光栅传感系统,包括光源、光纤环形器、光栅阵列、FP滤波器、光电探测器、FPGA控制系统、高速模数转换模块、WiFi模块、云平台、Android端上位机；通过无线传输和云端通信的方式实现数据发送和接收功能,配合上位机软件的实现数据的采集处理与观测控制。本发明采用了无线传输的通信方式将光纤光栅传感数据发送给云平台,通过云端通信可以在移动设备上远程实时监测被测对象的温度、压力等信息。(The invention discloses a fiber bragg grating sensing system based on cloud communication, which comprises a light source, a fiber optic circulator, a grating array, an FP filter, a photoelectric detector, an FPGA control system, a high-speed analog-to-digital conversion module, a WiFi module, a cloud platform and an Android end upper computer; the data sending and receiving functions are realized in a wireless transmission and cloud communication mode, and the data acquisition, processing and observation control are realized by matching with upper computer software. The invention adopts a wireless transmission communication mode to send the fiber bragg grating sensing data to the cloud platform, and can remotely monitor information such as temperature, pressure and the like of the measured object on the mobile equipment in real time through cloud communication.)

1. The utility model provides a fiber grating sensing system based on high in clouds communication which characterized in that: the system comprises a light source, an optical fiber circulator, a grating array, an FP filter, a photoelectric detector, an FPGA control system, a high-speed analog-to-digital conversion module, a WiFi module, a cloud platform and an Android end upper computer;

the light source outputs a continuous spectrum, and the continuous spectrum is injected into the grating array through one port of the optical fiber circulator; different gratings selectively reflect the wavelengths meeting the Bragg conditions, and the reflection spectrum is transmitted to an FP filter from another port of the optical fiber circulator to be demodulated; the output of the FP filter is connected into a photoelectric detector, the light power is converted into voltage amplitude in an equal proportion, the voltage amplitude is transmitted to a high-speed analog-to-digital conversion module, and then an analog signal is converted into a digital signal; the FPGA control system receives digital signals, samples the digital signals and transmits the digital signals to the cloud platform through the WiFi module, and the Android end upper computer is connected with the cloud platform through the API address and the APIKey of the equipment.

2. The fiber grating sensing system based on cloud communication of claim 1, wherein: the demodulation of the FP filter needs to be assisted by a periodic triangular wave signal generated by a loading signal generator.

3. The fiber grating sensing system based on cloud communication of claim 1, wherein: the high-speed digital-to-analog conversion module converts a digital signal transmitted by the FPGA control system into an analog signal to drive the FP filter.

4. The fiber grating sensing system based on cloud communication of claim 1, wherein: the grating array is composed of two reference gratings without temperature drift and a sensing grating.

5. The fiber grating sensing system based on cloud communication of claim 1, wherein: the WiFi module is communicated with the cloud platform in a data transmission mode of an EDP protocol to generate OneNET cloud communication virtual equipment.

Technical Field

The invention relates to the technical field of sensing systems, in particular to a fiber bragg grating sensing system based on cloud communication.

Background

Fiber Bragg Gratings (FBGs) occupy an important position in the sensing field by virtue of the characteristics of all-Fiber manufacturing and wavelength modulation. Especially in the fields of health monitoring of national defense and scientific work, electric power systems, civil engineering projects and the like, the fiber bragg grating is an indispensable part. The method for demodulating the sensing grating has universality by considering the unique characteristic of the sensing parameter on the central wavelength modulation of the fiber Bragg grating. The invention selects a Tunable Fiber FP Filter as a wavelength demodulation device, combines characteristic parameters of a double-reference-grating dynamic calibration FP Filter, and utilizes a mode that WiFi transmits data to a cloud platform and the cloud platform is connected with a mobile terminal by utilizing an API address, thereby developing a set of Fiber grating sensing system based on cloud communication.

Disclosure of Invention

The invention aims to solve the problems that: the fiber grating sensing system based on cloud communication is characterized in that data transmission between the fiber grating sensing system and upper computer software of an Android terminal is achieved in a cloud communication mode, collected information can be observed on mobile equipment, and the practicability of the fiber grating sensing system is improved.

The technical scheme provided by the invention for solving the problems is as follows: a fiber grating sensing system based on cloud communication comprises a light source, a fiber circulator, a grating array, an FP filter, a photoelectric detector, an FPGA control system, a high-speed analog-to-digital conversion module, a WiFi module, a cloud platform and an Android upper computer;

the light source outputs a continuous spectrum, and the continuous spectrum is injected into the grating array through one port of the optical fiber circulator; different gratings selectively reflect the wavelengths meeting the Bragg conditions, and the reflection spectrum is transmitted to an FP filter from another port of the optical fiber circulator to be demodulated; the output of the FP filter is connected into a photoelectric detector, the light power is converted into voltage amplitude in an equal proportion, the voltage amplitude is transmitted to a high-speed analog-to-digital conversion module, and then an analog signal is converted into a digital signal; the FPGA control system receives digital signals, samples the digital signals and transmits the digital signals to the cloud platform through the WiFi module, and the Android end upper computer is connected with the cloud platform through the API address and the APIKey of the equipment.

Preferably, the demodulation operation of the FP filter needs to be assisted by a periodic triangular wave signal generated by a loading signal generator.

Preferably, the filter further comprises a high-speed digital-to-analog conversion module and a driving signal amplification circuit, wherein the high-speed digital-to-analog conversion module converts a digital signal transmitted by the FPGA control system into an analog signal for driving the FP filter.

Preferably, the grating array is composed of two temperature drift-free reference gratings and a sensing grating.

Preferably, the WiFi module is communicated with the cloud platform in a data transmission mode of an EDP protocol to generate the OneNet cloud communication virtual device.

Compared with the prior art, the invention has the advantages that: according to the invention, data transmission with the upper computer software of the Android terminal is realized in a cloud communication mode, collected information can be observed on mobile equipment, and the practicability of the fiber grating sensing system is improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a system diagram of the present invention;

FIG. 2 is a connection diagram of a WiFi module and an Android end upper computer of the invention

Based on the above principle and the functional requirements of the demodulation system, the following describes the functional division of the modules of fig. 2:

(1) the external WiFi wireless connection module is connected with an OneNET cloud platform end through an EDP protocol, the cloud platform sends data to upper computer software of the mobile terminal through an API address, and information is displayed on the Android upper computer end through an application program of the upper computer;

(2) the Android end upper computer interface operation can also send an instruction to the WiFi module;

(3) the WiFi module adopts a 2.4GHz frequency band transmission technology and carries out coding encryption on the frequency band, so that data loss and interference in transmission are prevented;

(4) and transmitting the data to the wireless module through the serial port.

Detailed Description

The following detailed description of the embodiments of the present invention will be provided with reference to the accompanying drawings and examples, so that how to implement the embodiments of the present invention by using technical means to solve the technical problems and achieve the technical effects can be fully understood and implemented.

A fiber grating sensing system based on cloud communication comprises a light source, a fiber circulator, a grating array, an FP filter, a photoelectric detector, an FPGA control system, a high-speed analog-to-digital conversion module, a WiFi module, a cloud platform and an Android upper computer;

the light source outputs a continuous spectrum, and the continuous spectrum is injected into the grating array through one port of the optical fiber circulator; different gratings selectively reflect the wavelengths meeting the Bragg conditions, and the reflection spectrum is transmitted to an FP filter from another port of the optical fiber circulator to be demodulated; the output of the FP filter is connected into a photoelectric detector, the light power is converted into voltage amplitude in an equal proportion, the voltage amplitude is transmitted to a high-speed analog-to-digital conversion module, and then an analog signal is converted into a digital signal; the FPGA control system receives digital signals, samples the digital signals and transmits the digital signals to the cloud platform through the WiFi module, and the Android end upper computer is connected with the cloud platform through the API address and the APIKey of the equipment.

Furthermore, the demodulation operation of the FP filter needs to be assisted by a periodic triangular wave signal generated by a loading signal generator.

The high-speed digital-to-analog conversion module converts a digital signal transmitted by the FPGA control system into an analog signal to drive the FP filter.

Furthermore, the grating array is composed of two reference gratings without temperature drift and a sensing grating.

Further, the WiFi module is communicated with the cloud platform in a data transmission mode of an EDP (electronic data processing) protocol to generate OneNet cloud communication virtual equipment; the communication with the internet can be realized without a gateway; the mobile terminal equipment is connected with the WiFi in a configuration mode, so that signals acquired by fiber bragg grating sensing through wide area network remote display are achieved, and real-time changes of measured physical quantities can be efficiently observed under the local area network.

The specific principle of the invention is as follows: the light source outputs continuous spectrum, the continuous spectrum is injected into the grating array through the port 1-2 of the optical fiber circulator, different gratings selectively reflect the wavelength meeting the Bragg condition, and the reflected spectrum is transmitted to the FP filter from the port 2-3 of the optical fiber circulator to be demodulated. The demodulation of the FP filter needs to be assisted by a periodic triangular wave signal generated by a loading signal generator.

And adjusting the frequency and amplitude of the signal generator, loading the signal to the FP filter, and driving the FP filter to continuously and periodically scan the reflection spectrum P (lambda) of the grating array so as to obtain the time domain distribution P (t) of the reflection spectrum of the grating array. The output of the FP filter is connected into a photoelectric detector, and the light power is converted into the voltage amplitude in an equal proportion, so that the corresponding wavelength value can be solved by examining the peak position in a single period according to the characteristic relation of the F-filter.

The sampling and processing of the photoelectric signals are completed by combining the FPGA with the high-speed ADC module. It should be noted that the driving of the FP filter and the ADC sampling action need to be performed synchronously to ensure the accuracy of wavelength calculation, and the synchronous processing is completed inside the main control FPGA of the demodulation system.

In order to realize human-computer interaction, an ESP8266WiFi module is adopted to transmit data to an OneNET cloud platform, upper computer software of an Android end is developed, and the upper computer software is connected with cloud data through an API address, so that various data such as temperature waveforms can be displayed in real time.

Creating cloud equipment: 1. and registering the user. Logging in the OneNet official website, clicking a 'registration' button, and registering an account. 2. Create a product and select the access protocol that it needs. After logging in an account, opening a developer center, clicking 'create a product', selecting an EDP protocol in the text, and inputting product information such as a product name, a product category and the like to complete the creation of the product. 3. The device is created and information such as the ID of the device is recorded. By clicking the additional equipment on the webpage, the name and the serial number of the equipment (namely the authentication information of the equipment) need to be input, and the serial number of the newly-built equipment is recorded and can be used during software development. 4. A data stream is created. And (4) opening a product development interface, entering a data stream template, adding the data stream template, and inputting a data stream name, a unit name and a unit symbol to finish adding.

After the data of the hardware equipment is transmitted into the cloud data stream, the platform can also generate a line graph in the data stream according to the time sequence. The corresponding device ID and APIKey, data stream name are modified in the development board code to ensure that ESP8266 can send data onto the data stream of the virtual device. And burning the codes into a development board, and starting the development board after debugging is correct. The WiFi device quickly shows ESP8266 is connected to WiFi after startup. The OneNET cloud device is opened, showing that ESP8266 has connected the cloud device "ESP", which shows the online status.

And finally, installing the application to the mobile phone by using Android Studio, clicking the application to enter a user login interface, inputting a set password, then jumping to a data display interface, displaying data in a time reverse order, and displaying a numerical value and time on each item on ListView. And skipping to the graphical interface after clicking the Chat.

The foregoing is merely illustrative of the preferred embodiments of the present invention and is not to be construed as limiting the claims. The present invention is not limited to the above embodiments, and the specific structure thereof is allowed to vary. All changes which come within the scope of the invention as defined by the independent claims are intended to be embraced therein.