CN203551105U - Accelerometer wireless network node module for vibration detection - Google Patents

Abstract

The utility model discloses an accelerometer wireless network node module for vibration detection. The accelerometer wireless network node module comprises a sending module and a receiving module. The sending module comprises a power supply circuit, a sensor circuit and a single-chip microcomputer, wherein the power supply circuit is respectively connected with the sensor circuit and the single-chip microcomputer, and the sensor circuit is connected with the single-chip microcomputer. A sending end also comprises a radio frequency circuit. The radio frequency circuit is respectively connected with the power supply circuit and the single-chip microcomputer. The sensor circuit employs an ADXL202 double-shaft accelerometer. According to the utility model, an accelerometer is employed for measuring small angle inclination and vibration of an automobile or a bridge and emitting wireless signals through the radio frequency circuit, the detection is sensitive, the transmission is convenient, and the power consumption is quite low.

Description

An acceleration sensor wireless network node module for vibration detection

technical field

The utility model relates to an acceleration sensor wireless network node module used for vibration detection, which belongs to the fields of anti-theft or bridge measurement and control.

Background technique

With the continuous development of society, automobiles have become an important means of transportation for people to travel, and the anti-theft of automobiles has increasingly become the focus of people's attention. At present, the car anti-theft system mainly relies on the door locks. Criminals often commit crimes when there are few people and quiet, and even directly use a trailer to tow the car away, making it impossible for car owners to guard against it.

In addition to car anti-theft, in the field of bridge safety, the detection of bridge vibration is an important indicator to measure the safety factor of bridges. The impact of vehicle speed on bridge vibration is relatively small, while the smoothness has a great impact on bridge vibration. The lower the road surface grade , the more severe the vibration of the bridge. Therefore, the vibration detection of bridges is very important. Currently used bridge vibration detection has a quartz crystal temperature and frequency sensor. The advantage of this acceleration sensor is that it has good response characteristics to temperature, vibration and dynamics. But his shortcomings also have many, a series of problems such as short service life appear in the engineering of bridges.

Utility model content

In order to solve the problems of traditional car anti-theft and bridge structure health detection, the utility model aims to provide an acceleration sensor wireless network node module for vibration detection.

In order to realize above-mentioned technical purpose, the technical scheme of the utility model is:

An acceleration sensor wireless network node module for vibration detection, including a sending module and a receiving module, the sending module includes a power supply circuit, a sensor circuit and a single-chip microcomputer, the power supply circuit is respectively connected to the sensor circuit and the single-chip microcomputer, and the sensor circuit is connected to the single-chip microcomputer , characterized in that: the sending end also includes a radio frequency circuit, and the radio frequency circuit is respectively connected to the power supply circuit and the single-chip microcomputer; the sensor circuit adopts an ADXL202 biaxial acceleration sensor.

Among them, the above-mentioned single-chip microcomputer adopts C8051F912 single-chip microcomputer, and the radio frequency circuit includes AT86RF212 radio frequency chip, balanced-unbalanced converter, low-pass filter chip and antenna connected in sequence, and the AT86RF212 radio frequency chip is connected to the single-chip microcomputer.

Among them, the P0.1 port, P1.0 port, P1.1 port, P1.2 port, P1.3 port, P1.4 port and P1.5 port of the above-mentioned C8051F912 single-chip microcomputer are respectively connected with the IRQ port of the AT86RF212 radio frequency chip, The SCLK terminal, MISO terminal, MOSI terminal, SEL terminal, /RST terminal and SLP_TR terminal are connected; the P0.6 port and P0.7 port of the C8051F912 microcontroller are respectively connected to the Xout and Yout ports of the ADXL202 dual-axis acceleration sensor, and the P0.6 port and P0.7 port is configured as capture mode.

After adopting the above-mentioned technical scheme, the beneficial effect brought:

(1) The ADXL202 dual-axis acceleration sensor used in this utility model can measure dynamic or static acceleration within the range of 0-5kHz and ±2g. The measurement of acceleration can be used for vibration detection, and the spatial direction of the object can be determined by using the static acceleration of gravity as the input vector. If the car tilts or vibrates at a small angle, the acceleration sensor will detect it and transmit the signal to the microcontroller, and then transmit a wireless signal through the radio frequency circuit to inform the owner of the abnormality of the car, which greatly improves the safety of the car;

(2) The utility model uses wireless sensor technology and wireless transmission, which makes the monitoring of objects more convenient and improves safety; the use of dry batteries for power supply reduces the cumbersome wiring and saves costs to a certain extent; power consumption of the processor, reducing node power consumption.

Description of drawings

Fig. 1 is a system structure diagram of the utility model.

Fig. 2 is a specific circuit diagram of the transmitting module of the present invention.

Explanation of symbols: U1——low-pass filter chip; U2——balanced-unbalanced converter; P1——antenna.

Detailed ways

The technical solutions of the present utility model will be described in detail below in conjunction with the accompanying drawings.

The system structural block diagram of the present utility model as shown in Figure 1, comprises sending module and receiving module, and described sending module comprises power supply circuit, sensor circuit and single-chip microcomputer, and described power supply circuit connects sensor circuit and single-chip microcomputer respectively, and sensor circuit connects single-chip microcomputer , characterized in that: the sending end also includes a radio frequency circuit, and the radio frequency circuit is respectively connected to the power supply circuit and the single-chip microcomputer; the sensor circuit adopts an ADXL202 biaxial acceleration sensor. The duty cycle of the two pulse width signal output terminals Xout and Yout output signals of the ADXL202 dual-axis acceleration sensor is proportional to the acceleration in the X-axis direction and the Y-axis direction, respectively. The single-chip microcomputer adopts C8051F912 single-chip microcomputer, and the radio frequency circuit includes AT86RF212 radio frequency chip, balanced-unbalanced converter, low-pass filter chip and antenna connected in sequence, and the AT86RF212 radio frequency chip is connected to the single-chip microcomputer. The P0.1 port, P1.0 port, P1.1 port, P1.2 port, P1.3 port, P1.4 port and P1.5 port of the C8051F912 microcontroller are respectively connected to the IRQ port, SCLK port and MISO port of the AT86RF212 radio frequency chip. terminal, MOSI terminal, SEL terminal, /RST terminal and SLP_TR terminal; the P0.6 and P0.7 ports of the C8051F912 microcontroller are respectively connected to the Xout and Yout terminals of the ADXL202 dual-axis acceleration sensor, and the P0.6 port and P0.7 port is configured in capture mode.

In this example, the specific circuit diagram of the transmitting module of the present invention as shown in FIG. 2 is adopted. The sending module of the utility model includes a power supply circuit, a sensor circuit, a single-chip microcomputer and a radio frequency circuit. The power supply circuit uses 3 dry batteries in series in the same direction, the positive pole of diode D1 is connected to the negative pole of dry battery, the negative pole of diode D1 is filtered by capacitor C1, and one end is connected to the analog power input terminal VCC_SYS2 of C8051F912 single-chip microcomputer and AT86RF212 radio frequency chip, and the other end is passed through a resistor R1 is connected to the digital power input terminal VCC_SYS1 that supplies power for the C8051F912 single-chip microcomputer, the biaxial acceleration sensor and the AT86RF212 radio frequency chip. In the sensor circuit, the Xfilt end and Yfilt end of the ADXL202 dual-axis acceleration sensor are grounded after the capacitor C2 and the capacitor C3 respectively, and the T2 end is grounded after the resistor R2. The duty cycle of the two pulse width signal output terminals Xout and Yout of the ADXL202 dual-axis acceleration sensor is proportional to the acceleration in the X-axis direction and the Y-axis direction respectively. The Xout and Yout ends of the ADXL202 dual-axis acceleration sensor are respectively connected to the P0.6 and P0.7 ports of the C8051F912 microcontroller, and the P0.6 and P0.7 ports are configured as capture mode to capture the ADXL202 dual-axis acceleration sensor Xout and Yout The level change of the terminal is used to measure the duty cycle of the output signal to calculate the corresponding acceleration. The P0.1 port, P1.0 port, P1.1 port, P1.2 port, P1.3 port, P1.4 port and P1.5 port of the C8051F912 microcontroller are respectively connected to the IRQ port, SCLK port and MISO port of the AT86RF212 radio frequency chip. Terminal, MOSI terminal, SEL terminal, /RST terminal and SLP_TR terminal connection. The communication between C8051F912 single-chip microcomputer and AT86RF212 radio frequency chip adopts serial peripheral interface protocol, in which the single-chip microcomputer is the SPI master device, and the radio frequency chip is the SPI slave device. Pins 1, 2, 3, 6, 7, 9, 10, 14, 16, 17, 18, 21, 27, 30, 31 and 32 of the AT86RF212 radio frequency chip are grounded, and pin 13 is connected to pin 12 and passed through The bypass capacitor C10 is grounded, and the pin 15 is connected to the ground by the 3.3V power supply and the power supply bypass capacitor C11. The XTAL1 and XTAL2 terminals of the AT86RF212 radio frequency chip are connected to the ground after passing through the capacitors C7 and C6 respectively, and the crystal oscillator X2 is connected between the connection point of XTAL1 and C7 and the connection point of XTAL2 and C6. The EVDD terminal of the AT86RF212 radio frequency chip is connected to the digital power input terminal VCC_SYS1, and the connection point of the EVDD terminal to the digital power input terminal VCC_SYS1 is grounded through the power supply bypass capacitor C4, and the AVDD terminal is grounded through the bypass capacitor C5. The two-way differential antenna pins RFP and RFN of the AT86RF212 radio frequency chip are respectively connected to the balanced-unbalanced converter U2 through the RF coupling capacitors C9 and C8, and the balanced-unbalanced converter U2 is connected to the low-pass filter chip U1 to realize differential signal direction. Conversion of single-ended signals. The low-pass filter chip U1 is connected with the antenna P1, and sends the data to the receiving module in the form of wireless transmission.

The above embodiments are only to illustrate the technical ideas of the utility model, and cannot limit the protection scope of the utility model with this. Any changes made on the basis of the technical solutions according to the technical ideas proposed by the utility model all fall into the scope of the utility model. within the scope of the new protection.

Claims (3)

1. an acceleration sensor wireless network node module for vibration detection, comprising a sending module and a receiving module, the sending module includes a power supply circuit, a sensor circuit and a single-chip microcomputer, and the described power supply circuit is respectively connected to the sensor circuit and the single-chip microcomputer, and the sensor circuit Connecting to the single-chip microcomputer, it is characterized in that: the sending end also includes a radio frequency circuit, and the radio frequency circuit is respectively connected to the power supply circuit and the single-chip microcomputer; the sensor circuit adopts an ADXL202 biaxial acceleration sensor. 2. a kind of acceleration sensor wireless network node module that is used for vibration detection according to claim 1, is characterized in that: described single-chip microcomputer adopts C8051F912 single-chip microcomputer, and described radio frequency circuit comprises the AT86RF212 radio frequency chip, balance- Unbalanced converter, low-pass filter chip and antenna, AT86RF212 radio frequency chip connected to the microcontroller. 3. A kind of acceleration sensor wireless network node module for vibration detection according to claim 2, characterized in that: the P0.1 port, P1.0 port, P1.1 port, and P1.2 port of the C8051F912 single-chip microcomputer Port, P1.3 port, P1.4 port and P1.5 port are respectively connected with IRQ port, SCLK port, MISO port, MOSI port, SEL port, /RST port and SLP_TR port of AT86RF212 radio frequency chip; P0. Port 6 and P0.7 are respectively connected to the Xout and Yout ports of the ADXL202 dual-axis acceleration sensor, and the ports P0.6 and P0.7 are configured as capture mode.

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