Vibrating wire type synchronous acquisition equipment

Abstract

The utility model provides vibrating wire type synchronous acquisition equipment, which comprises an excitation power supply, a switch group comprising a plurality of electronic switches and a plurality of signal processing modules arranged corresponding to a plurality of vibrating wire type sensors, and the signal processing modules comprise signal switching circuits electrically connected with the vibrating wire type sensors. The excitation power supply is electrically connected with the plurality of signal switching circuits through the plurality of electronic switches, the signal processing module is electrically connected with the field programmable gate array controller, and the field programmable gate array controller is electrically connected with the electronic switches, the GPS time service module and the microcontroller. Acquisition time is issued to a microcontroller and compared with a local clock, so that an acquisition instruction is transmitted to a field programmable gate array controller, and the field programmable gate array controller transmits a second pulse signal at the next moment when the acquisition instruction is received as a trigger signal to an electronic switch and a signal switching circuit. And the excitation power supply synchronously excites the plurality of vibrating wire sensors, so that multi-channel synchronous acquisition is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of engineering measurement, in particular to a vibrating string type synchronous acquisition device. Background Art

[0002] Existing vibrating string acquisition equipment generally expands the channel through a relay or analog switch at the front end of the signal chain, and then converts it into a digital signal through a shared signal conditioning circuit, analog-to-digital converter and microcontroller to calculate the final frequency value.

[0003] When multi-channel vibrating-string sensor measurements are required, multi-channel expansion can be achieved through chip selection.

[0004] However, this method can only realize multi-channel polling (serial) acquisition. In some measurement scenarios with high requirements for real-time and synchronization, the current serial acquisition equipment cannot comprehensively and accurately evaluate the stress state of the structure at a certain moment and in a certain period of time. The cumulative channel delay of all channels may be several minutes or even more than ten minutes, which is very unfavorable for the overall stress characteristic monitoring of the monitored structure. Utility Model Content

[0005] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a vibrating-string synchronous acquisition device, aiming to solve the technical problem that in the prior art, multi-channel serial acquisition is achieved through chip selection. In some measurement scenarios with high requirements for real-time and synchronization, the cumulative channel delay of all channels may be several minutes or even more than ten minutes, affecting the accuracy of monitoring the overall stress characteristics of the monitored structure.

[0006] In order to achieve the above purpose, the utility model is implemented through the following technical solutions:

[0007] A vibrating string synchronous acquisition device is used for synchronously acquiring data from a plurality of vibrating string sensors. The vibrating string synchronous acquisition device comprises an excitation power supply, a switch group and a plurality of signal processing modules corresponding to the plurality of vibrating string sensors. The switch group comprises a plurality of electronic switches. The signal processing module comprises a signal switching circuit electrically connected to the vibrating string sensor. The excitation power supply is electrically connected to the plurality of signal switching circuits through the plurality of electronic switches respectively. The signal processing module is electrically connected to a field programmable gate array controller. The field programmable gate array controller is electrically connected to the electronic switches, a GPS timing module and a microcontroller respectively. The GPS timing module is used for providing a timestamp and a second pulse signal to the field programmable gate array controller. The microcontroller is electrically connected to an RTC clock for providing a local clock so as to calibrate the local clock through the timestamp. The microcontroller is also used for comparing the sampling time and the local clock so as to issue an acquisition instruction to the field programmable gate array controller. The field programmable gate array controller is used for performing logic control on the electronic switches and the signal switching circuit based on the acquisition instruction and the second pulse signal.

[0008] Compared with the prior art, the beneficial effect of the utility model is that when multiple vibrating string sensors need to be synchronously collected, the time is collected by the microcontroller, and the microcontroller compares the collection time with the local clock. When the two times are close, the microcontroller transmits the collection instruction to the field programmable gate array controller, and the field programmable gate array controller uses the second pulse signal of the next moment of receiving the collection instruction as a trigger signal, and transmits the trigger signal to the electronic switch and the signal switching circuit, synchronously switches the signal chain, so that the excitation power supply synchronously excites different vibrating string sensors, and completes synchronous collection through the signal processing module, thereby realizing synchronous collection of multiple channels. In measurement scenarios with high requirements for real-time and synchronization, the time difference generated when collecting data between different channels can be avoided, thereby improving the monitoring accuracy of the overall stress characteristics of the monitored structure.

[0009] Furthermore, the signal processing module also includes an amplifying circuit, a filtering circuit and a waveform shaping circuit which are electrically connected to the signal switching circuit in sequence, and the waveform shaping circuit is electrically connected to the field programmable gate array controller.

[0010] Furthermore, the signal switching circuit includes a signal relay LS1, the 4th pin and the 13th pin of the signal relay LS1 are electrically connected to the vibrating string sensor, the 8th pin of the signal relay LS1 is electrically connected to the electronic switch, the 9th pin of the signal relay LS1 is grounded, and the 6th pin and the 11th pin of the signal relay LS1 are electrically connected to the amplifier circuit.

[0011] Furthermore, a resistor R4 and a diode D4 are connected in series between the 4th pin and the 13th pin of the signal relay LS1 , and a diode D3 is provided between the 1st pin and the 16th pin of the signal relay LS1 .

[0012] Furthermore, the 16th pin of the signal relay LS1 is connected to the collector of the transistor Q2, the emitter of the transistor Q2 is grounded, the base of the transistor Q2 is electrically connected to the SW pin through the resistor R10, and a resistor R11 is set between the base and the emitter of the transistor Q2.

[0013] Furthermore, the electronic switch includes a photocoupler D1, the third pin of the photocoupler D1 is connected to the excitation power supply, the fourth pin of the photocoupler D1 is connected to the eighth pin of the signal relay LS1, the first pin of the photocoupler D1 is connected to the collector of the transistor Q1 through a resistor R1, the base of the transistor Q1 is connected to the PS pin through a resistor R2, the emitter of the transistor Q1 is grounded, and a resistor R3 is set between the emitter and the base of the transistor Q1.

[0014] Furthermore, the electronic switch further includes a capacitor C1, and opposite ends of the capacitor C1 are respectively connected to opposite ends of the resistor R2.

[0015] Furthermore, the amplification circuit includes an instrument amplifier U1, the non-inverting input terminal of the instrument amplifier U1 is electrically connected to the 6th pin of the signal relay LS1 through a resistor R6, the inverting input terminal of the instrument amplifier U1 is electrically connected to the 11th pin of the signal relay LS1 through a resistor R15, and the output terminal of the instrument amplifier is electrically connected to the filter circuit.

[0016] Furthermore, the filtering circuit includes a bivalent active high-pass filter and a quadrivalent active low-pass filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a structural block diagram of a vibrating-string synchronous acquisition device in an embodiment of the utility model;

[0018] Figure 2 It is a circuit diagram of a signal switching circuit, an amplifying circuit and an excitation circuit in a vibrating-string synchronous acquisition device in an embodiment of the utility model;

[0019] Figure 3 A circuit diagram of a waveform shaping circuit in a vibrating-string synchronous acquisition device in an embodiment of the utility model;

[0020] Description of main component symbols:

[0021] 1. Vibrating string sensor; 2. Signal switching circuit; 3. Electronic switch; 4. Excitation power supply; 5. Amplification circuit; 6. Filter circuit; 7. Waveform shaping circuit; 8. Field programmable gate array controller; 9. Microcontroller; 10. GPS timing module; 11. Communication module; 12. RTC clock.

[0022] The following specific implementation manner will further illustrate the present utility model in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0023] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0024] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0026] See also Figures 1 to 3The vibrating-string synchronous acquisition device in the embodiment of the utility model is used for synchronously acquiring data from a plurality of vibrating-string sensors 1. The vibrating-string synchronous acquisition device comprises an excitation power supply 4, a switch group and a plurality of signal processing modules corresponding to the plurality of vibrating-string sensors 1. The switch group comprises a plurality of electronic switches 3. The signal processing module comprises a signal switching circuit 2 electrically connected to the vibrating-string sensor 1. The excitation power supply 4 is electrically connected to a plurality of the signal switching circuits 2 through a plurality of the electronic switches 3 respectively. The electronic switches 3 and the signal switching circuit 2 are used to switch the vibrating-string synchronous acquisition device to an excitation mode or an acquisition mode. It can be understood that each of the vibrating-string sensors 1 corresponds to a channel for independently demodulating signals, namely, the signal processing module. After the excitation power supply 4 applies an excitation voltage to the vibrating-string sensor 1, the acquisition signals of each of the vibrating-string sensors 1 can be synchronously processed by each of the signal processing modules. The signal processing module is electrically connected to the field programmable gate array controller 8, and the field programmable gate array controller 8 is electrically connected to the electronic switch 3. When the electronic switch 3 and the signal switching circuit 2 connect the vibrating string sensor 1 and the excitation power supply 4, the excitation power supply 4 provides an excitation voltage, thereby enabling the vibrating string sensor 1 to obtain a collection signal. When the vibrating string sensor 1 completes signal collection, the electronic switch 3 and the signal switching circuit 2 connect the vibrating string sensor 1 and the field programmable gate array controller 8 to complete the processing and collection of signal collection.

[0027] In this embodiment, the signal processing module also includes an amplifier circuit 5, a filter circuit 6 and a waveform shaping circuit 7 which are electrically connected to the signal switching circuit 2 in sequence. The waveform shaping circuit 7 is electrically connected to the field programmable gate array controller 8. The amplifier circuit 5 is used to amplify the acquisition signal of the vibrating string sensor 1 to ensure a certain signal-to-noise ratio. The filter circuit 6 is used to filter out interference noise outside the bandwidth in the acquisition signal. The acquisition signal after filtering is a sinusoidal wave signal with damping attenuation. By using the waveform shaping circuit 7, it can be converted into a square wave of the same frequency, which is convenient for the field programmable gate array controller 8 to use a time domain method for frequency measurement.

[0028] Specifically, the signal switching circuit 2 includes a signal relay LS1, the 4th pin and the 13th pin of the signal relay LS1 are electrically connected to the vibrating string sensor 1, the 8th pin of the signal relay LS1 is electrically connected to the electronic switch 3, the 9th pin of the signal relay LS1 is grounded, the 6th pin and the 11th pin of the signal relay LS1 are electrically connected to the amplifier circuit 5, and a resistor R4 and a diode D4 are connected in series between the 4th pin and the 13th pin of the signal relay LS1. Since the core excitation and induction component of the vibrating string sensor 1 is an inductor, and the current of the inductor cannot change suddenly, therefore, in the process of sending the excitation voltage, a reverse spike pulse signal will be generated after each pulse ends. By setting the resistor R4 and the diode D4, the reverse spike second impulse can be absorbed to avoid damage to the circuit or introduction of additional interference. A diode D3 is set between the 1st pin and the 16th pin of the signal relay LS1. The diode D3 is a freewheeling diode that can absorb the sudden voltage at both ends of the signal relay LS1.

[0029] The 16th pin of the signal relay LS1 is connected to the collector of the transistor Q2, the emitter of the transistor Q2 is grounded, the base of the transistor Q2 is electrically connected to the SW pin through the resistor R10, and a resistor R11 is set between the base and the emitter of the transistor Q2. The resistor R10, the resistor R11 and the transistor Q2 constitute the driving circuit of the signal relay LS1. The field programmable gate array controller 8 can switch between excitation and collection by enabling and disabling the DW pin.

[0030] The electronic switch 3 includes a photocoupler D1, which is a Darlington type photocoupler with a large driving current and a fast response speed, and can meet the requirements of sending millisecond pulse signals. The third pin of the photocoupler D1 is connected to the excitation power supply 4 (VCC_H), the fourth pin of the photocoupler D1 is connected to the eighth pin of the signal relay LS1, the first pin of the photocoupler D1 is connected to the collector of the transistor Q1 through a resistor R1, the base of the transistor Q1 is connected to the PS pin through a resistor R2, the emitter of the transistor Q1 is grounded, and a resistor R3 is set between the emitter and the base of the transistor Q1. Preferably, the electronic switch 3 also includes a capacitor C1, and the opposite ends of the capacitor C1 are respectively connected to the opposite ends of the resistor R2. By setting the capacitor C1, the response speed of the transistor Q1 can be improved. The field programmable gate array controller 8 controls the electronic switch 3 through the PS pin.

[0031] The amplifying circuit 5 includes an instrument amplifier U1, a non-inverting input terminal of the instrument amplifier U1 is electrically connected to the 6th pin of the signal relay LS1 through a resistor R6, an inverting input terminal of the instrument amplifier U1 is electrically connected to the 11th pin of the signal relay LS1 through a resistor R15, an output terminal of the instrument amplifier is electrically connected to the filter circuit 6, and a resistor R9 and a resistor R13 are arranged in series between the non-inverting input terminal and the inverting input terminal of the instrument amplifier, and the resistor R9 and the resistor R13 are used to provide a bias circuit for the instrument amplifier U1.

[0032] The filtering circuit 6 includes a second-order active high-pass filter and a fourth-order active low-pass filter. The passband cutoff frequency of the second-order active high-pass filter is generally 400 Hz, which is the lower limit of the output frequency of the vibrating string sensor 1, and can filter out power frequency interference and other interference and noise below 400 Hz; the passband cutoff frequency of the fourth-order active low-pass filter is 4000 Hz, which is the upper limit of the output frequency of the vibrating string sensor 1, and is used to filter out aliasing interference, external electromagnetic interference and noise above 4000 Hz.

[0033] The waveform shaping circuit 7 includes a zero-crossing comparator U15, the third pin (non-inverting input terminal) of the zero-crossing comparator U15 is electrically connected to the filter circuit 6 through a resistor R44, the fourth pin (inverting input terminal) of the zero-crossing comparator U15 is grounded through a resistor R43, the first pin (output terminal) of the zero-crossing comparator U15 is electrically connected to the field programmable gate array controller 8, a resistor R45 is set between the third pin and the first pin of the zero-crossing comparator U15, and a resistor R42 is set between the fourth pin and the fifth pin of the zero-crossing comparator U15.

[0034] The field programmable gate array controller 8 is also electrically connected to a GPS timing module 10 and a microcontroller 9. The GPS timing module 10 is used to provide a timestamp and a second pulse signal to the field programmable gate array controller 8. The microcontroller 9 is electrically connected to an RTC clock 12 for providing a local clock to calibrate the local clock through the timestamp. The microcontroller 9 is also used to compare the sampling time and the local clock to issue a collection instruction to the field programmable gate array controller 8. The field programmable gate array controller 8 is used to perform logical control on the electronic switch 3 and the signal switching circuit 2 based on the collection instruction and the second pulse signal. In this embodiment, the microcontroller 9 is electrically connected to a communication module 11, and the communication module 11 is connected to a remote server to transmit the sampling time to the microcontroller 9. It can be understood that after the sampling is completed, the adopted data can be transmitted to the remote server through the communication module 11.

[0035] When multiple vibrating string sensors 1 need to be collected synchronously, the time is collected from the microcontroller 9, and the microcontroller 9 compares the collection time with the local clock. When the two times are close, the microcontroller 9 transmits the collection instruction to the field programmable gate array controller 8. The field programmable gate array controller 8 uses the second pulse signal at the next moment of receiving the collection instruction as a trigger signal, and transmits the trigger signal to the electronic switch 3 and the signal switching circuit 2, and synchronously switches the signal chain, so that the excitation power supply 4 synchronously excites different vibrating string sensors 1, and completes synchronous collection through the signal processing module, thereby realizing synchronous collection of multiple channels. In measurement scenarios with high requirements for real-time and synchronization, the time difference generated when collecting data between different channels can be avoided, thereby improving the monitoring accuracy of the overall stress characteristics of the monitored structure.

[0036] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0037] The above-mentioned embodiments only express several implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent of the utility model. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the utility model, and these all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A vibrating string synchronous data acquisition device, used for synchronously acquiring data from a plurality of vibrating string sensors, characterized in that: The vibrating string synchronous acquisition device includes an excitation power supply, a switch group and a plurality of signal processing modules corresponding to a plurality of vibrating string sensors, the switch group includes a plurality of electronic switches, the signal processing module includes a signal switching circuit electrically connected to the vibrating string sensor, the excitation power supply is electrically connected to a plurality of signal switching circuits through a plurality of electronic switches, the signal processing module is electrically connected to a field programmable gate array controller, the field programmable gate array controller is electrically connected to the electronic switches, a GPS timing module and a microcontroller, the GPS timing module is used to provide a timestamp and a second pulse signal to the field programmable gate array controller, the microcontroller is electrically connected to an RTC clock for providing a local clock to calibrate the local clock through the timestamp, the microcontroller is also used to compare the sampling time and the local clock to issue an acquisition instruction to the field programmable gate array controller, and the field programmable gate array controller is used to perform logical control on the electronic switch and the signal switching circuit based on the acquisition instruction and the second pulse signal.

2. The vibrating-wire synchronous acquisition device according to claim 1, characterized in that: The signal processing module also includes an amplifying circuit, a filtering circuit and a waveform shaping circuit which are electrically connected to the signal switching circuit in sequence, and the waveform shaping circuit is electrically connected to the field programmable gate array controller.

3. The vibrating-wire synchronous acquisition device according to claim 2, characterized in that: The signal switching circuit includes a signal relay LS1, wherein the 4th pin and the 13th pin of the signal relay LS1 are electrically connected to the vibrating string sensor, the 8th pin of the signal relay LS1 is electrically connected to the electronic switch, the 9th pin of the signal relay LS1 is grounded, and the 6th pin and the 11th pin of the signal relay LS1 are electrically connected to the amplifier circuit.

4. The vibrating-wire synchronous acquisition device according to claim 3, characterized in that: A resistor R4 and a diode D4 are connected in series between the 4th pin and the 13th pin of the signal relay LS1 , and a diode D3 is provided between the 1st pin and the 16th pin of the signal relay LS1 .

5. The vibrating-wire synchronous acquisition device according to claim 3, characterized in that: The 16th pin of the signal relay LS1 is connected to the collector of the transistor Q2, the emitter of the transistor Q2 is grounded, the base of the transistor Q2 is electrically connected to the SW pin through the resistor R10, and a resistor R11 is provided between the base and the emitter of the transistor Q2.

6. The vibrating-wire synchronous acquisition device according to claim 3, characterized in that: The electronic switch includes a photocoupler D1, the third pin of the photocoupler D1 is connected to an excitation power supply, the fourth pin of the photocoupler D1 is connected to the eighth pin of the signal relay LS1, the first pin of the photocoupler D1 is connected to the collector of the transistor Q1 through a resistor R1, the base of the transistor Q1 is connected to the PS pin through a resistor R2, the emitter of the transistor Q1 is grounded, and a resistor R3 is set between the emitter and the base of the transistor Q1.

7. The vibrating-wire synchronous acquisition device according to claim 6, characterized in that: The electronic switch further includes a capacitor C1 , and opposite ends of the capacitor C1 are respectively connected to opposite ends of the resistor R2 .

8. The vibrating-wire synchronous acquisition device according to claim 3, characterized in that: The amplification circuit includes an instrument amplifier U1, the non-inverting input terminal of the instrument amplifier U1 is electrically connected to the 6th pin of the signal relay LS1 through a resistor R6, the inverting input terminal of the instrument amplifier U1 is electrically connected to the 11th pin of the signal relay LS1 through a resistor R15, and the output terminal of the instrument amplifier is electrically connected to the filter circuit.

9. The vibrating-wire synchronous acquisition device according to claim 2, characterized in that: The filter circuit includes a bivalent active high-pass filter and a quadrivalent active low-pass filter.

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