CN109000686A - A kind of digital Fibre Optical Sensor test macro - Google Patents

Abstract

The invention discloses a kind of digital Fibre Optical Sensor test macros.Its system structure includes: Power Management Unit, uses 5V DC power supply for system power supply.MCU electricity control unit, it is using 16 RL78 Series MCUs as master controller.Infrared digital photoelectric sensing unit, for perceiving the photooptical data of ambient enviroment.Photooptical data display unit, for showing photooptical data.Data storage cell, for the storage of system parameters and the storage of photooptical data.Relay unit, the threshold value for completing photooptical data act.Real-time opto-electronic data WIFI net leaflet member, is used for Various types of data real-time display in other terminals.Man-machine interaction unit, for completing the setting of system parameter with the display of relevant parameter.

Description

An all-digital optical fiber sensor test system

technical field

The invention can be used for non-contact object detection and color recognition in special environments (such as strong electromagnetic interference), and belongs to the technical fields of infrared photoelectric sensing and Internet of Things.

Background technique

Optical fiber sensing technology is to measure and modulate the light emitted by the light source transmitted through the optical fiber, causing changes in the characteristics of the light (such as intensity, phase, frequency, etc.), and the modulated light is transmitted to the receiving end through the optical fiber and passed through the photodetector and solution. The modulator demodulates a sensing technology to be measured from the outside world. However, the sensing part of the traditional sensing system adopts the through-beam and reflective structure, and the circuit part generally uses a discrete analog circuit to drive the light emitting tube, and the device has many shortcomings such as large dispersion and complex structure.

This design is to integrate the drive of the light emission tube, photoelectric conversion, and A/D conversion output. Through the specific digital interface communication between the MCU and the chip, the photoelectric conversion data is read for digital signal processing, so that it can be combined with the integrated circuit Such as good parameter consistency, low power consumption, small size, improved stability and many other advantages, while the infrared digital sensor chip has the above advantages, overcomes many shortcomings of the traditional discrete circuit structure, and the author combines the Internet of Things technology to realize A miniaturized and intelligent all-digital optical fiber sensing test system.

Contents of the invention

On the basis of some traditional optical fiber sensing systems based on intensity modulation, the invention uses infrared digital photoelectric sensing chips to design a fully digital optical fiber sensing testing system. The solution of the all-digital optical fiber sensing test system is as follows: the system uses MCU as the main control unit, uses infrared proximity sensors as infrared LED drive and photoelectric conversion output unit, RTC chip and data memory EEPROM for time reading and real-time photoelectric data Storage, WIFI transparent transmission module realizes network transmission of photoelectric data, buttons and LCD display unit complete functions such as human-computer interaction. Experimental results show that the system can be used for non-contact object detection in special environments. The hardware structure of the all-digital optical fiber sensing test system is as follows: it mainly consists of power management unit, MCU electrical control unit, infrared digital photoelectric sensing unit, photoelectric data display unit, data storage unit, relay unit, real-time photoelectric data WIFI network transmission unit, Human-computer interaction unit constitutes.

Further stated: the power management unit, the system uses a 5V DC power supply for the system power supply. The 5V power supply is connected to the relay drive power pin and the ULN2803 pin, and then two three-terminal voltage regulator chips LM1117-3.3V are used to supply LCD1602 and ESP8266 respectively.

Further, the MCU electrical control unit, the control unit selects R5F104LEA, which has small size, low power consumption, and extremely rich resources on the chip, supports IIC communication, UART communication, and has A/D converter, timer, on-chip button interrupt function, A high-speed on-chip oscillator clock is built in, and of course an external crystal oscillator circuit can also be used as the system clock. This system uses an external crystal oscillator with a frequency of 18.432MHz.

Further, the infrared digital photoelectric sensing unit, the core chip of this unit is ISL29021, this chip is a built-in infrared LED driver and supports IIC interface and infrared sensor.

Further, the photoelectric data display unit and the data display components of the entire system are five-in-one common cathode digital tubes and LCD liquid crystal displays. The digital tube driver chip uses BC7275, which supports SPI interface communication and has a chip selection function. The four CLK and MOSI lines of the unit are connected to the SPI serial input clock terminal of the main control unit and the data output terminal of the SPI port. The main control unit uses four chip selection lines to connect to the chip selection terminals of the four drive chips respectively. The remaining pins of the chip are connected to the segment selection and bit selection terminals of the corresponding five-digit common cathode digital tube. The LCD selects the LCD1602 device with a working voltage of 3.3V, and its data line can be directly connected to the I/O port of the main control chip for control.

Further, the data storage unit uses AT24C02, AT24C08 and RX8025 chips. AT24C02 stores relay thresholds or other system parameters, RX stores or reads time values, and AT24C08 records photoelectric data and collection time. All three chip pins can be connected to the IICA interface of the main control unit.

Further, the relay unit uses an ATQ209 relay device connected to an external ULN2803 driver chip to drive four relays. The opening and closing of the relay work depends on the comparison between the collected photoelectric data and the set initial value. If the collected value is less than the initial value, the relay will be closed, otherwise it will be disconnected.

Further, the real-time photoelectric data WIFI network transmission unit adopts the ESP8266 wireless module, which embodies the basic mechanism of the Internet of Things, and displays the collected data in other single-board display modules or mobile terminals. This design is to display the collected data on the ARM side.

Further, the human-computer interaction unit adopts a button trigger mode, and this design uses four buttons: the functions are the mode key, the selection key, the up and down key, and the down key. Connect them to the interrupt pins on the main control unit.

Therefore the beneficial effect of the present invention is: this design adopts the digital proximity sensor to carry out the design of the electrical part of the all-digital optical fiber sensing test system, and the digital proximity sensor integrates functions such as LED drive, optical signal reception, signal amplification modulation, A/D conversion, Compared with the traditional circuit system equipped with discrete electronic components, it has the characteristics of small size, low power consumption, low distortion, strong anti-interference ability, etc., and uses wireless modules to realize photoelectric data from local display to other mobile display. Function.

Description of drawings

Fig. 1 is a circuit design structural diagram of the present invention

Fig. 2 is a flow chart of software design of the present invention

Fig. 3 is a system physical diagram of the present invention

Fig. 4a is the through-beam optical fiber sensing test diagram of the present invention

Fig. 4 b is the through-beam optical fiber sensing test diagram of the present invention

Fig. 4c is the through-beam optical fiber sensing test diagram of the present invention

Fig. 4d is the through-beam optical fiber sensing test diagram of the present invention

Fig. 5 is a reflective optical fiber sensor test diagram of the present invention

Detailed ways

The following content will further illustrate the content of the invention and its principles in conjunction with the accompanying drawings. The examples given are used to explain the invention, not to limit the scope of application of the invention.

Fig. 1 is the circuit design structure diagram of the all-digital optical fiber sensing test system of the present invention, with R5F104LEA as the MCU main control chip, externally connected four-way infrared digital photoelectric sensor ISL29021 chip, and externally connected four-way five-bit common cathode digital tubes, corresponding to Four photoelectric sensors. Because the main controller reads the photoelectric data sensed by the sensor through its own IIC interface, and then displays the data on the five-digit digital tube; then in order to improve the real-time operability of the system, the function of four relays is added , buttons, LCD1602, WIFI network transmission module, and data memory EEPROM to facilitate the storage of system parameters and photoelectric data.

Fig. 2 is the software design flowchart of the present invention, at first each module unit is initialized, and each parameter setting initial value, core part is the pattern selection of system, and this part is finished by the key interruption part, and this system is set in five by the user In one mode: data collection, mode setting, threshold setting, data query, power query, etc. The specific functions are as follows:

(1) In the data acquisition mode, the completed functions are: the main control unit reads the photoelectric data collected by the infrared digital photoelectric chip through the IIC interface and displays it on the digital tube; reads the time information of the RX8025 and stores the photoelectric data in the In AT24C08, due to space constraints, a total of 64 recent records can be stored, each record contains four channels of photoelectric data and collection time; compare the collected photoelectric data with the set value, when the collected value is less than the set value , the relay of the corresponding road is closed, otherwise it is disconnected; the status of each relay is displayed on the LCD; the real-time photoelectric data is transmitted through the WIFI network through ESP8266.

(2) The function completed in mode setting mode is: to set and display the working status of each infrared digital photoelectric chip. This article uses two of the four working modes of the infrared digital optoelectronic chip: programmable one-time proximity sensing and programmable continuous proximity sensing, and its infrared LED drive current is adjustable in four levels: 12.5mA, 25mA, 50mA, and 100mA , The resolution of the ADC is 4 bits, 8 bits, 12 bits and 16 bits, and the resolution of the ADC is related to the integration time. In this way, 32 sensing modes can be formed. At the same time, the infrared digital photoelectric chip can also be set in the power-down state through the register, that is, its sensing collection is prohibited. In summary, the user can perform 33 modes for each sensing unit according to actual needs. choose. The sensing mode of the four-channel infrared digital photoelectric chip will be displayed on the LCD. The user can select a sensing unit to be tested by the selection key, and then change the mode of the channel by the up or down key.

(3) In the threshold setting mode, the function it completes is: set the threshold of each relay action and display it on the LCD. This threshold is used in data acquisition mode.

(4) The function of the data query mode is to query the latest 64 data records collected in the data collection mode. The LCD will display the photoelectric data of a certain channel on the current page and its collection time. The switching of the channel is realized by the selection key, and the switching of the page is completed by the up and down keys.

(5) The completed function of the power inquiry mode is: display the collected lithium battery voltage on the LCD, and at the same time prompt the user on the LCD whether the battery voltage is normal.

In each mode, when the lithium battery is low, the LED light will flash to remind the user to replace the lithium battery.

Fig. 3 is the actual figure of the present invention, and each module is as shown in the figure, what the nixie tube shows at present is the second channel, and its light intensity is 32636, and the first, third, and fourth channels are not working, so OFF is displayed on the LCD, and the second channel The second channel shows ON, indicating that it is working at the current moment.

Fig. 4a is the test diagram of the through-beam optical fiber sensor of the present invention, the distance between the beams of this figure is 0-20mm, and the ADC data is almost unchanged at the beginning, but with the increase of the distance between the beams, the ADC data decreases Very big.

Fig. 4b is the through-beam type optical fiber sensor test diagram of the present invention, and the through-beam distance of this figure is 20mm-100mm, and with the increase of the through-beam distance, the ADC output data value decreases, but the change value of reduction is compared with The shooting distance is that the change value of 0-20mm is small.

Fig. 4c is the test diagram of the through-beam optical fiber sensor of the present invention, the through-beam distance of this figure is 0-160mm, and this figure is that after adding the focusing mirror, the sensing distance increases significantly, and with the increase of the through-beam distance, its The light intensity output value decreases relatively slowly.

Fig. 4d is a test diagram of the through-beam optical fiber sensor of the present invention, the distance between the beams of this figure is 160-480mm, during the test, it can be found that the light intensity decreases continuously with the increase of the distance between the beams, The decreasing speed is relatively fast, and the latter distance decreases relatively slowly.

Further, as shown in Figures 4a, 4b, 4c, and 4d, it can be concluded that within a certain range, due to the strong light, the output is almost unchanged, and then it is inversely proportional. In the latter distance, the output value decreases relative to the previous one. Decrease slowly. After adding the focusing mirror, the sensing distance is significantly enhanced.

Fig. 5 is a reflective optical fiber sensor test diagram of the present invention, the test process is to select similar objects of different colors as the detected object, move the distance between the optical fiber probe and the object, and record the ADC of the infrared photoelectric chip displayed by the nixie tube output value.

Further, the reflective pipeline sensing test diagram in Figure 5 shows that when the distance between the fiber optic probe and the object is relatively close, the ADC output increases as the distance of the detected object increases, but then increases and decreases, Therefore, it can be concluded that the wave peak in the figure is the best detection distance.

The above is the specific embodiment of the invention.

To sum up: the present invention uses a digital proximity sensor to replace relatively traditional discrete components, which has the advantages of small size, small distortion, and strong anti-interference ability, and uses the network transmission module to display real-time data on other terminals, and finally The author also built through-beam and reflective basic structures, and measured data on them. The results can be used for non-contact object detection in special environments, which are widely used and can be further promoted in the future.

Claims (8)

1. An all-digital optical fiber sensing test system, characterized in that it includes: a power management unit, an MCU electrical control unit, an infrared digital photoelectric sensing unit, a photoelectric data display unit, a data storage unit, and a real-time photoelectric data WIFI network transmission unit , and a human-computer interaction unit; the power management unit uses a 5V DC power supply to power the system; the MCU electrical control unit uses a 16-bit RL78 series MCU as the main controller; the infrared digital photoelectric sensor unit is used for Sensing and collecting photoelectric data of the external environment; the photoelectric data display unit is used to display the photoelectric data collected by the infrared digital photoelectric sensing unit; the data storage unit is used for storage of system parameters and photoelectric data; the The relay unit is used to complete the threshold action of the photoelectric data; the real-time photoelectric data WIFI network transmission unit displays the data of the photoelectric data display unit on the mobile network terminal, and the network terminal can be a mobile phone, a tablet, etc.; the man-machine The interactive unit completes the setting of the system parameters and the display of the setting parameters. 2. A kind of all-digital optical fiber sensing test system according to claim 1, characterized in that, said power management unit adopts 5V DC power supply to supply power to the whole system; what said electrical control unit selected is 16 Renesas The RL78 series MCU produced by the company is used as the main controller; the infrared digital photoelectric sensing unit includes a photoelectric sensor chip ISL29021, an infrared LED high-power SFH4056 chip; the photoelectric data display unit includes a BC7275 five-digit digital tube driver chip, and five One-bit common cathode digital tube; the data storage unit includes memory AT24C02, AT24C08 chip and RX8025 real-time clock chip; the relay unit includes a relay chip ATQ209 and a drive relay chip ULN2803; the real-time photoelectric data WIFI network transmission unit is selected from ESP8266 to complete; the human-computer interaction unit includes a key input device and an LCD1602 display device. 3. A kind of all-digital optical fiber sensing test system according to claim 1, characterized in that, its power management unit utilizes a 5V power supply to access the relay drive power supply pin and the ULN2803 power supply pin, and access to the three terminals The voltage regulator chip LM1117-3.3 converts the 5V voltage to 3.3V voltage to supply power for the rest of the system. 4. A kind of all-digital optical fiber sensing test system according to claim 1, is characterized in that, the main control chip R5F104LEA of the RL78 series MCU that its electrical control unit selects, promptly has low power consumption, high performance, can Debugging has many advantages; it also supports IIC communication, UART communication, A/D converter, timer, on-chip buttons, built-in high-speed on-chip oscillator clock and other functions. 5. A kind of all-digital optical fiber sensing test system according to claim 1, is characterized in that, its data storage unit, adopted AT24C02 off-chip memory is used for the storage of system parameter; Adopt RX8025 chip to be used for reading time information , using AT24C08 chip for recording photoelectric data and acquisition time. 6. A kind of all-digital optical fiber sensing test system according to claim 1, characterized in that, its infrared digital photoelectric sensing unit includes a photoelectric sensor chip ISL29021, which is a built-in infrared LED driver and supports IIC interface infrared The sensor has an A/D converter up to 16 bits inside, and the infrared LED drive current is adjustable and optional, and has many advantages of high frequency and low noise. 7. A kind of all-digital optical fiber sensor test system according to claim 1, characterized in that, its photoelectric data display unit is to respectively connect four-way BC7275 five-digit nixie tube driver chips with four-way five-in-one common cathode digital The tubes are connected to each other, and then the collected photoelectric data can be displayed on the digital tube; the BC7275 five-digit digital tube driver chip supports SPI interface communication and has a chip selection function; the CLK and MOSI lines of the four BC7275 are connected to the main control unit. The SPI serial input clock terminal, the SPI port data output terminal, the main control unit uses four chip selection lines to connect to the chip selection terminals of the four drive chips, and the other pins of the chip are connected to the corresponding five-digit common cathode digital tube. Segment selection and bit selection end. 8. A kind of all-digital optical fiber sensing test system according to claim 1, characterized in that, its human-computer interaction unit adopts the key interruption mode to complete the system mode selection, including five modes: respectively data acquisition, working mode Setting, threshold setting, data query, power query mode; its key setting functions: mode key, selection key, up key, and down key, which are respectively connected to the key interrupt pins of the main control unit.