Temperature measurement and compensation device for passive wireless ultrasonic detection

Abstract

The invention discloses a temperature measurement and compensation device for passive wireless ultrasonic detection, and relates to the technical field of passive wireless ultrasonic detection, and the device comprises a wireless sensing end and an external collection end. The wireless sensing end comprises a micro-control unit, a temperature measuring unit, an electric quantity storage unit and a radio frequency communication unit; the radio frequency communication unit communicates with an external acquisition end, and obtains energy from electromagnetic waves emitted by the external acquisition end for a subsequent circuit. The electric quantity storage unit stores electric energy captured by the radio frequency communication unit; in order to optimize the power consumption of the wireless sensing end, when the voltage value of the electric quantity storage unit is low, the subsequent circuit does not work, and when the voltage value is high, the subsequent circuit starts to work; the micro-control unit controls the temperature measurement unit to obtain a temperature measurement result and transmits the temperature measurement result to the radio frequency communication unit, and the radio frequency communication unit transmits the temperature measurement result to an external acquisition end. Temperature measurement is carried out through a passive and wireless method, and temperature compensation of passive and wireless ultrasonic detection can be further achieved.

Description

Technical Field

[0001] The present application relates to the technical field of passive wireless ultrasonic detection, and in particular to a temperature measurement and compensation device for passive wireless ultrasonic detection. Background Art

[0002] In ultrasonic testing, the importance of temperature compensation cannot be ignored. The propagation speed of ultrasonic waves is closely related to temperature. Changes in temperature will cause changes in the speed of sound, thus affecting the accuracy and reliability of the test results. For example, ultrasound is used for thickness measurement, stress measurement, bolt axial force measurement, guided wave detection, defect location or liquid level measurement. However, with the development of wireless electromagnetic coupling ultrasonic excitation and reception technology, ultrasonic sensors are gradually becoming passive and wireless. However, the current technology is mainly passive wireless acquisition of ultrasonic signals, and there is no effective passive wireless temperature measurement compensation technology. Summary of the invention

[0003] The purpose of the present application is to provide a temperature measurement and compensation device for passive wireless ultrasonic detection, which can realize temperature measurement and compensation for passive wireless ultrasonic detection.

[0004] To achieve the above objectives, this application provides the following solutions:

[0005] The present application provides a temperature measurement and compensation device for passive wireless ultrasonic detection, comprising: a wireless sensor terminal and an external acquisition terminal;

[0006] The wireless sensor terminal specifically includes: a microcontroller unit, a temperature measurement unit, a power storage unit and a radio frequency communication unit; the radio frequency communication unit is connected to the external acquisition terminal;

[0007] The microcontrol unit is connected to the temperature measuring unit, the power storage unit and the radio frequency communication unit respectively; the power storage unit is also connected to the radio frequency communication unit and the temperature measuring unit respectively; the radio frequency communication unit communicates and transmits energy with the external acquisition end through a radio magnetic field;

[0008] The radio frequency communication unit is used to receive electromagnetic wave energy;

[0009] The temperature measuring unit is used to obtain temperature measurement results;

[0010] The microcontrol unit is used to control the temperature measuring unit and read the temperature measurement result, and transmit the temperature measurement result to the radio frequency communication unit; the microcontrol unit is also used to measure the voltage of the power storage unit and control the temperature measuring unit according to the voltage of the power storage unit.

[0011] Optionally, the power storage unit is a capacitor.

[0012] Optionally, the power storage unit is a battery.

[0013] Optionally, the temperature measuring unit is a thermocouple.

[0014] Optionally, the temperature measuring unit includes multiple thermistors, and different thermistors have different temperature measurement ranges.

[0015] Optionally, the radio frequency communication unit includes: an RFID chip and an RFID antenna;

[0016] The RFID chip is respectively connected to the power storage unit, the micro control unit and the RFID antenna;

[0017] The RFID antenna is used to receive electromagnetic wave energy;

[0018] The RFID chip is used to obtain temperature measurement results; the RFID chip is also used to use electromagnetic wave energy to power the power storage unit and subsequent circuits.

[0019] Optionally, the RFID chip is an RFID chip with energy conversion function.

[0020] Optionally, the radio frequency communication unit further comprises: an energy conversion circuit;

[0021] The energy conversion circuit is connected to the RFID chip and the power storage unit respectively.

[0022] Optionally, a communication module is provided inside the RFID antenna;

[0023] The communication module is connected to the external acquisition unit; the communication module is used to send the temperature measurement result to a designated area of ​​the external acquisition unit for storage.

[0024] Optionally, the temperature measurement result is one or more of a resistance value, a voltage value, a temperature value or an AD sampling result.

[0025] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0026] The present application provides a temperature measurement and compensation device for passive wireless ultrasonic detection, including: a microcontroller unit, a temperature measuring unit, a power storage unit and a radio frequency communication unit; the radio frequency communication unit is used to receive electromagnetic wave energy; the microcontroller unit is used to control the power storage unit to store electromagnetic wave energy and obtain the voltage value of the power storage unit, and use the electromagnetic wave energy to power the electromagnetic wave energy when the voltage value of the power storage unit is lower than the discharge voltage, and use the power storage unit to power the electromagnetic wave energy when the voltage value of the power storage unit reaches the discharge voltage; the temperature measuring unit is used to obtain the temperature measurement result; the microcontroller unit is also used to transmit the temperature measurement result to the radio frequency communication unit. By performing wireless coupled passive measurement of temperature, or combining wireless coupled measurement with a small power supply, and using the temperature result measured in this way to compensate for the passive wireless ultrasonic measurement result, the problem of no temperature compensation in the current passive wireless ultrasonic signal measurement is filled, and temperature measurement can be achieved in a long period and at a low cost (low hardware cost and small size). BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 This is a schematic structural diagram of a temperature measurement and compensation device for passive wireless ultrasonic detection in one embodiment of the present application.

[0029] Figure 2 This is a temperature range matching circuit diagram in one embodiment of the present application.

[0030] Figure 3 This is a simplified structural diagram of a temperature measurement and compensation device for passive wireless ultrasonic detection in one embodiment of the present application. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0033] In an exemplary embodiment, Figure 1 and Figure 3 As shown, a temperature measurement and compensation device for passive wireless ultrasonic detection is provided, comprising: a wireless sensor end and an external collection end; wherein the wireless sensor end specifically comprises: a microcontroller unit, a temperature measuring unit, a power storage unit and a radio frequency communication unit; the microcontroller unit is respectively connected to the temperature measuring unit, the power storage unit and the radio frequency communication unit; the power storage unit is also respectively connected to the radio frequency communication unit and the temperature measuring unit; the radio frequency communication unit communicates and transmits energy with the external collection end through a radio magnetic field; the radio frequency communication unit is used to receive electromagnetic wave energy; the temperature measuring unit is used to obtain temperature measurement results; the microcontroller unit is used to control the temperature measuring unit and read the temperature measurement results, and transmit the temperature measurement results to the radio frequency communication unit; the microcontroller unit is also used to measure the voltage of the power storage unit, and control the temperature measuring unit according to the voltage of the power storage unit. The wake-up mode of the microcontroller unit comprises a first wake-up mode and a second wake-up mode; the priority of the first wake-up mode is higher than the second wake-up mode; the first wake-up mode is to wake up the microcontroller unit by using the state angle of the radio frequency communication unit; the second wake-up mode is to wake up the microcontroller unit by the power supply of the RFID antenna in the radio frequency communication unit. wherein, the power storage unit is a capacitor or a battery. the temperature measuring unit is a thermocouple or a thermistor. The temperature measuring unit includes a plurality of thermistors, and different thermistors have different temperature measuring ranges.

[0034] When using thermistors to measure a larger temperature range, the resistance value varies greatly, which will cause the problem of low measurement accuracy. Use a combination of thermistors with different temperature measurement ranges for measurement. First, measure the thermistor with a possibly larger resistance value to determine whether the temperature value is within the measurement range of the thermistor. If it is within the measurement range, terminate the measurement; otherwise, measure the thermistor with the next resistance value and continue measuring until the measurement result is appropriate. In order to improve the measurement accuracy and make full use of the ADC dynamic range, multiple temperature range matching circuits are set for each thermistor. Different temperature ranges correspond to different thermistor resistance values, so the matching circuits for different temperature ranges are temperature range matching circuits for different resistance values. For example: it can be divided into 100~1k ohms, 1k~10k ohms, 10k~100k ohms, 100k~1M ohms, 1M~10M ohms and other ranges. The temperature range matching circuit is as follows Figure 2 .

[0035] The radio frequency communication unit includes: an RFID chip and an RFID antenna; the RFID chip is respectively connected to the power storage unit, the micro control unit and the RFID antenna; the RFID antenna is used to receive electromagnetic wave energy; a communication module is provided inside the RFID antenna; the communication module is connected to the external acquisition unit; the communication module is used to send the temperature measurement result to the designated area of ​​the external acquisition unit for storage. The RFID chip is used to obtain the temperature measurement result. The temperature measurement result is one or more of the resistance value, the voltage value or the temperature value. The RFID chip is an RFID chip with an energy conversion function or the radio frequency communication unit also includes an energy conversion circuit; the energy conversion circuit is respectively connected to the RFID chip and the power storage unit.

[0036] Through the RF communication unit and the excitation antenna (RFID antenna), wireless communication is performed with the RF unit; while communicating, an induced voltage can be generated on the receiving end antenna or coil, and the voltage is collected for energy, such as rectification and filtering, to achieve wireless energy supply. The RF communication unit obtains the temperature acquisition result by reading the specified area of ​​the RFID chip, and the result includes the current working status of the sensor (such as whether to start acquisition, the reliability of the acquisition result, the measured value, etc.). The measured value here can be voltage, resistance, converted temperature, etc. For example, by measuring the resistance value of the thermistor, the resistance value can be directly output as a result to the external acquisition unit, which is converted into temperature by the acquisition unit. The resistance value can also be measured and converted into a temperature value and output to the external acquisition unit. Or by measuring the voltage value of the thermocouple, the voltage value can be directly output as a result to the external acquisition unit, which is converted into temperature by the acquisition unit. The voltage value can also be measured and converted into a temperature value and output to the external acquisition unit.

[0037] At the sensor end, the RFID antenna receives electromagnetic wave energy from the external acquisition unit, activates the internal communication module, communicates with the external acquisition unit, and sends data to the designated storage area. Electromagnetic wave energy is collected and stored in a battery or capacitor. When the voltage of the battery or capacitor reaches the operating voltage of the communication module, communication can be performed. When the transmitting unit and the receiving unit are close, no battery or capacitor is needed, and the received electromagnetic wave energy is directly converted into direct current. At this time, the voltage is higher, and the internal communication module starts to work.

[0038] At the sensor end, the energy received by the RFID antenna can be collected through a separate energy conversion circuit or directly through the RFID chip; the energy is stored through a capacitor or battery to form a relatively stable power supply to power the subsequent circuit. Two solutions: Use an external energy conversion circuit to collect energy, and use an RFID chip power supply with this function to power the acquisition unit. Here, the acquisition unit should at least include a signal that measures the temperature sensing unit, and store the measurement results in the designated storage area of ​​the RFID chip through the communication interface. The written data includes: status data, measurement results, etc. The status parameters at least include: an identification of whether the data is valid; in addition, there may be: electromagnetic signal strength, software version number, etc. The measurement result is one or more of resistance value, voltage value, and temperature value.

[0039] Furthermore, in order to improve efficiency and reduce unnecessary power consumption. The voltage of the power supply can be used as a wake-up signal for the acquisition unit, that is, when the voltage is high, the acquisition unit is started for acquisition. The power supply voltage is low and temperature measurement cannot be achieved, but the acquisition unit has been started, resulting in high power consumption, causing the power supply to charge slowly. Since the present application is for temperature compensation of ultrasonic measurement results, the temperature measurement process is performed during ultrasonic measurement and does not require real-time. Its wake-up is that the sensor end captures the electromagnetic waves of external excitation for energy storage, and starts to collect temperature when the energy storage is sufficient. Therefore, the acquisition action is before, after or during ultrasonic measurement. But there is no need to measure all the time.

[0040] The radio frequency communication unit can perform continuous acquisition and ensure continuous power supply until a stable measurement result can be obtained. When the results of multiple measurements fluctuate slightly, the measurement result can be considered stable. After each reading, the RFID result can be reset to avoid reading the previous measurement result. The status bit and measurement result are saved in the specified data area of ​​the RFID. Each time the RFID sends data to the external acquisition unit, the value of the specified data area is reset to a fixed value, which indicates that no temperature value is currently measured. When the RFID end can read the temperature value, modify the specified data area and write the measurement result and the result measurement status to the area. After the external acquisition unit reads the rewritten measurement value and status bit, it resets the specified data area.

[0041] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A temperature measurement and compensation device for passive wireless ultrasonic detection, characterized in that: include: Wireless sensor terminal and external collection terminal; The wireless sensor terminal specifically includes: a micro control unit, a temperature measurement unit, a power storage unit and a radio frequency communication unit; The microcontrol unit is connected to the temperature measuring unit, the power storage unit and the radio frequency communication unit respectively; the power storage unit is also connected to the radio frequency communication unit and the temperature measuring unit respectively; the radio frequency communication unit communicates and transmits energy with the external acquisition end through a radio magnetic field; The radio frequency communication unit is used to receive electromagnetic wave energy; The temperature measuring unit is used to obtain temperature measurement results; The microcontrol unit is used to control the temperature measuring unit and read the temperature measurement result, and transmit the temperature measurement result to the radio frequency communication unit; the microcontrol unit is also used to measure the voltage of the power storage unit and control the temperature measuring unit according to the voltage of the power storage unit.

2. The temperature measurement and compensation device for passive wireless ultrasonic detection according to claim 1 is characterized in that: The power storage unit is a capacitor.

3. The temperature measurement and compensation device for passive wireless ultrasonic detection according to claim 1 is characterized in that: The power storage unit is a battery.

4. The temperature measurement and compensation device for passive wireless ultrasonic detection according to claim 1 is characterized in that: The temperature measuring unit is a thermocouple.

5. The temperature measurement and compensation device for passive wireless ultrasonic detection according to claim 1, characterized in that: The temperature measuring unit includes a plurality of thermistors, and different thermistors have different temperature measuring ranges.

6. The temperature measurement and compensation device for passive wireless ultrasonic detection according to claim 5, characterized in that: The radio frequency communication unit includes: an RFID chip and an RFID antenna; The RFID chip is respectively connected to the power storage unit, the micro control unit and the RFID antenna; The RFID antenna is used to receive electromagnetic wave energy; The RFID chip is used to obtain temperature measurement results; the RFID chip is also used to use electromagnetic wave energy to power the power storage unit and subsequent circuits.

7. The temperature measurement and compensation device for passive wireless ultrasonic detection according to claim 6, characterized in that: The RFID chip is an RFID chip with energy conversion function.

8. The temperature measurement and compensation device for passive wireless ultrasonic detection according to claim 7, characterized in that: The radio frequency communication unit further includes: an energy conversion circuit; The energy conversion circuit is connected to the RFID chip and the power storage unit respectively.

9. The temperature measurement and compensation device for passive wireless ultrasonic detection according to claim 6, characterized in that: A communication module is provided inside the RFID antenna; The communication module is connected to the external acquisition unit; the communication module is used to send the temperature measurement result to a designated area of ​​the external acquisition unit for storage.

10. The temperature measurement and compensation device for passive wireless ultrasonic detection according to claim 6, characterized in that: The temperature measurement result is one or more of a resistance value, a voltage value, a temperature value or an AD sampling result.

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