System for measuring loosening degree of tower bolt based on laser signal gain adjustment

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By setting different reflectivity regions on the tower bolts and adjusting the laser signal gain, combined with differential amplification and processor unit processing, the problem of low accuracy in tower bolt vibration measurement in the prior art is solved, and the degree of loosening of tower bolts is accurately determined.

CN117740351BActive Publication Date: 2026-07-21STATE GRID HUBEI EXTRA HIGH VOLTAGE CO +1

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Patent Information

Authority / Receiving Office: CN · China
Patent Type: Patents(China)
Current Assignee / Owner: STATE GRID HUBEI EXTRA HIGH VOLTAGE CO
Filing Date: 2023-12-15
Publication Date: 2026-07-21

AI Technical Summary

Technical Problem

In existing technologies, laser-based methods for measuring tower bolt vibration suffer from low measurement accuracy and cannot accurately determine the degree of tower bolt vibration.

Method used

By setting up a tower bolt reflectivity unit with different reflectivity regions, and by performing gain adjustment processing on the laser signal, combined with a differential amplification module and a processor unit for signal processing, the degree of looseness of the tower bolts can be accurately determined.

Benefits of technology

The accuracy of determining the degree of looseness of tower bolts has been improved. By setting different reflectivity regions of the tower bolt reflectivity unit and adjusting the signal gain, combined with environmental factor compensation, the accurate measurement of the degree of looseness of tower bolts has been achieved.

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Abstract

The application discloses a kind of based on laser signal gain adjustment measuring pole tower bolt loosening degree system, comprising: laser emission unit, for emitting first frequency laser signal and second frequency laser signal;Laser receiving unit, laser receiving unit includes first sub-receiving unit and second sub-receiving unit;Preprocessing unit, preprocessing unit includes photoelectric conversion module, differential amplification module and AD conversion module;Pole tower bolt reflectivity unit, pole tower bolt reflectivity layer unit is arranged on the surface of pole tower bolt, and pole tower bolt reflectivity layer unit includes 2 or more reflectivity regions with different reflectivity;Processor unit is used for the pole tower bolt loosening degree determination processing of laser digital signal;Realize by setting pole tower bolt reflectivity unit has reflectivity region with different reflectivity and gain adjustment processing to laser signal signal, to improve the determination accuracy of pole tower bolt loosening and degree.

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Description

Technical Field

[0001] This invention relates to the field of laser measurement technology for tower vibration, and in particular to a system for measuring the looseness of tower bolts based on laser signal gain adjustment. Background Technology

[0002] Currently, most laser-based methods for measuring tower bolt vibration involve directly irradiating the bolt with a laser signal. However, since the reflectivity of the tower bolt is the same in any area of the bolt being measured, this method has certain limitations. Specifically, the measurement accuracy is not high, and the degree of tower bolt vibration cannot be accurately determined. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, this invention provides a system for measuring the looseness of tower bolts based on laser signal gain adjustment. This system improves the accuracy of determining the looseness and degree of tower bolts by setting reflectivity regions with different reflectivity in the tower bolt reflectivity unit and by adjusting the gain of the laser signal.

[0004] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0005] A system for measuring the looseness of tower bolts based on laser signal gain adjustment includes:

[0006] A laser emitting unit is used to emit a first frequency laser signal and a second frequency laser signal;

[0007] A laser receiving unit, comprising a first sub-receiving unit and a second sub-receiving unit, wherein the first sub-receiving unit is used to receive a first frequency laser signal and the second sub-receiving unit is used to receive a second frequency laser signal;

[0008] The preprocessing unit includes a photoelectric conversion module, a differential amplification module, and an AD conversion module. The differential amplification module is connected to both the photoelectric conversion module and the AD conversion module. The photoelectric conversion module performs voltage signal conversion processing on the first frequency laser signal and the second frequency laser signal, and transmits the signal to the differential amplification module. The differential amplification module receives the voltage signal transmitted from the photoelectric conversion module, performs signal gain adjustment processing, and transmits the signal to the AD conversion module. The AD conversion module receives the signal gain adjustment processing result transmitted from the differential amplification module, converts the signal gain adjustment processing result into a laser digital signal, and transmits it to the processor unit.

[0009] A tower bolt reflectivity unit is formed by setting a tower bolt reflectivity layer unit on the surface of the tower bolt. The tower bolt reflectivity layer unit includes two or more reflectivity regions with different reflectivity.

[0010] The processor unit is used to determine the degree of looseness of tower bolts from the laser digital signal.

[0011] Furthermore, the laser emitting unit includes a laser frequency emitting subunit, which emits laser signals of different frequencies based on a laser frequency control signal.

[0012] Furthermore, the laser frequency emitting subunit emits laser signals of different frequencies based on the laser frequency control signal, including the following steps:

[0013] The processor unit transmits the laser frequency control signal to the laser emitting unit;

[0014] The laser emitting unit generates a laser frequency control signal based on the transmitted laser emitting control signal and transmits it to the laser frequency emitting subunit;

[0015] The laser frequency emission subunit emits laser signals of different frequencies based on the laser frequency control signal.

[0016] Furthermore, the differential amplifier module includes: resistors R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, adjustable resistors R19 and R20, capacitors C1, C2, C3, C4, C5, and C6, and operational amplifiers U1, U2, U3, U4, U5, U6, U7, and U8. The photoelectric conversion module is connected to the positive terminal of operational amplifier U1. The inverting input terminal of operational amplifier U1 is connected to the non-inverting input terminal of operational amplifier U2, the non-inverting input terminal of operational amplifier U3, and the non-inverting input terminal of operational amplifier U4. The inverting input terminal of operational amplifier U1 is connected to one end of resistor R1, one end of resistor R5, and one end of capacitor C1. The inverting input terminal of operational amplifier U2 is connected to one end of resistor R2, one end of resistor R6, and one end of capacitor C2. The inverting input terminal of operational amplifier U3 is connected to one end of resistor R3, one end of resistor R7, and one end of capacitor C3. The inverting input terminal of operational amplifier U4 is connected to one end of resistor R4, one end of resistor R8, and one end of capacitor C4. The other end of resistor R1, the other end of resistor R2, and the other end of resistor R3 are connected to the other end of ... One end of the operational amplifier U1 and the other end of the resistor R4 are both grounded. The output of operational amplifier U1 is connected to one end of resistor R9, the other end of resistor R5, and the other end of capacitor C1, respectively. The output of operational amplifier U2 is connected to one end of resistor R11, the other end of resistor R6, and the other end of capacitor C2, respectively. The output of operational amplifier U3 is connected to one end of resistor R13, the other end of resistor R7, and the other end of capacitor C3, respectively. The output of operational amplifier U4 is connected to one end of resistor R15, the other end of resistor R8, and the other end of capacitor C4, respectively. The non-inverting input of operational amplifier U5 is connected to the other end of resistor R9 and one end of resistor R10, respectively. The non-inverting input of operational amplifier U5 is connected to resistor R... The other end of resistor R11 and one end of resistor R12 are connected. The non-inverting input of operational amplifier U6 is connected to the other end of resistor R13 and one end of resistor R14. The non-inverting input of operational amplifier U6 is connected to the other end of resistor R15 and one end of resistor R16. The other ends of resistors R12 and R16 are both grounded. The output of operational amplifier U5 is connected to the other end of resistor R10 and the non-inverting input of operational amplifier U7. The output of operational amplifier U6 is connected to the other end of resistor R14 and the non-inverting input of operational amplifier U8. The non-inverting input of operational amplifier U7 is connected to one end of resistor R17, one end of adjustable resistor R19, and one end of capacitor C5.The negative input terminal of operational amplifier U8 is connected to one end of resistor R18, one end of adjustable resistor R20, and one end of capacitor C6. The output terminal of operational amplifier U7 is connected to the other end of adjustable resistor R19, the other end of capacitor C5, and the AD conversion module. The output terminal of operational amplifier U8 is connected to the other end of adjustable resistor R20, the other end of capacitor C6, and the AD conversion module. The other ends of resistors R17 and R18 are both grounded.

[0017] Furthermore, the differential amplifier module receives the voltage signal transmitted from the photoelectric conversion module and performs signal gain adjustment processing, including the following steps:

[0018] The differential amplifier module performs noise filtering on the voltage signal transmitted by the photoelectric conversion module.

[0019] The differential amplifier module adjusts the signal gain based on adjustable resistors 19 and 20 to obtain a gain adjustment signal with equal amplitude.

[0020] Optionally, the material of the reflectivity region of the tower bolt reflectivity layer unit can be a metallic material.

[0021] Furthermore, the processor unit's processing of the laser digital signal to determine the degree of looseness of the tower bolts includes the following steps:

[0022] The processor unit performs laser feature extraction processing on the laser digital signal to obtain the reflectivity region characteristics of the laser-irradiated area and the reflectivity characteristics of the laser in the reflectivity layer unit of the tower bolt.

[0023] Based on the reflectivity characteristics of laser light in the reflectivity layer unit of tower bolts, it is determined whether the tower bolts are loose;

[0024] The degree of loosening of tower bolts is determined based on the reflectivity characteristics of the region illuminated by the laser and the reflectivity characteristics of the laser in the reflectivity layer unit of the tower bolts.

[0025] Furthermore, the processor unit performs tower bolt loosening displacement compensation based on environmental factor signals around the tower and the expansion coefficient of the tower bolt reflectivity layer unit.

[0026] Furthermore, the environmental factor signals around the tower include the temperature signal of the tower bolt reflectivity layer unit, the air temperature and humidity signal, and the ambient atmospheric pressure signal.

[0027] Furthermore, the processor unit performs tower bolt loosening displacement compensation based on environmental factor signals around the tower and the expansion coefficient of the tower bolt reflectivity layer unit, including the following steps:

[0028] Based on the expansion coefficient and temperature signal of the tower bolt reflectivity layer unit, the degree of expansion of the reflectivity region in the tower bolt reflectivity layer unit is determined.

[0029] The refractive index of ambient air is determined based on air temperature and humidity signals and ambient atmospheric pressure signals.

[0030] Based on the expansion degree of the reflectivity region in the reflectivity layer unit of the tower bolt and the refractive index of the ambient air, displacement compensation is performed on the loosening displacement of the tower bolt.

[0031] The beneficial effects of this invention are: by setting reflectivity regions with different reflectivity in the tower bolt reflectivity unit and by performing gain adjustment processing on the laser signal, the accuracy of determining the looseness and degree of tower bolts can be improved.

[0032] This system implements noise filtering processing on the voltage signal transmitted from the photoelectric conversion module via a differential amplifier module, thereby improving the signal-to-noise ratio. The differential amplifier module receives the voltage signal from the photoelectric conversion module and performs signal gain adjustment processing. Specifically, the differential amplifier module adjusts the signal gain based on adjustable resistors 19 and 20 to obtain a gain adjustment signal with equal amplitude. Noise filtering is then further performed through resistors R17 and R18, and capacitors C5 and C6, thus improving the signal-to-noise ratio.

[0033] This invention enables tower bolt loosening displacement compensation based on environmental factors around the tower and the expansion coefficient of the tower bolt reflectivity layer unit via the processor unit, thereby further improving the accuracy of measuring the degree of tower bolt loosening.

[0034] By utilizing the reflectivity characteristics of the laser-irradiated area and the reflectivity characteristics of the laser in the tower bolt reflectivity layer unit, the degree of looseness of the tower bolts can be accurately determined. Attached Figure Description

[0035] Figure 1 This is a circuit diagram of a differential amplifier module for a system for measuring the looseness of tower bolts based on laser signal gain adjustment, as described in this invention. Detailed Implementation

[0036] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0037] The following specific examples illustrate the implementation of this disclosure. Those skilled in the art can easily understand other advantages and effects of this disclosure from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. This disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this disclosure. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0038] Example 1:

[0039] A system for measuring the looseness of tower bolts based on laser signal gain adjustment includes:

[0040] A laser emitting unit is used to emit a first frequency laser signal and a second frequency laser signal;

[0041] A laser receiving unit, comprising a first sub-receiving unit and a second sub-receiving unit, wherein the first sub-receiving unit is used to receive a first frequency laser signal and the second sub-receiving unit is used to receive a second frequency laser signal;

[0042] The preprocessing unit includes a photoelectric conversion module, a differential amplification module, and an AD conversion module. The differential amplification module is connected to both the photoelectric conversion module and the AD conversion module. The photoelectric conversion module performs voltage signal conversion processing on the first frequency laser signal and the second frequency laser signal, and transmits the signal to the differential amplification module. The differential amplification module receives the voltage signal transmitted from the photoelectric conversion module, performs signal gain adjustment processing, and transmits the signal to the AD conversion module. The AD conversion module receives the signal gain adjustment processing result transmitted from the differential amplification module, converts the signal gain adjustment processing result into a laser digital signal, and transmits it to the processor unit.

[0043] A tower bolt reflectivity unit is formed by setting a tower bolt reflectivity layer unit on the surface of the tower bolt. The tower bolt reflectivity layer unit includes two or more reflectivity regions with different reflectivity.

[0044] The processor unit is used to determine the degree of looseness of tower bolts from the laser digital signal.

[0045] A laser emitting unit is used to emit a first frequency laser signal and a second frequency laser signal. The laser emitting unit includes a laser frequency emitting subunit, which emits laser signals of different frequencies based on a laser frequency control signal. A processor unit transmits the laser frequency control signal to the laser emitting unit. The laser emitting unit receives the laser emission control signal transmitted by the processor unit, generates a laser frequency control signal based on the transmitted laser emission control signal, and transmits it to the laser frequency emitting subunit. The laser frequency emitting subunit receives the laser frequency control signal transmitted by the processor unit and emits laser signals of different frequencies based on the laser frequency control signal; that is, the laser frequency emitting subunit emits the first frequency laser signal and the second frequency laser signal based on the laser frequency control signal.

[0046] It should be noted that the laser frequency transmitting subunit is used to transmit laser signals of different frequencies based on the laser frequency control signal. That is, the laser frequency transmitting subunit transmits a first frequency laser signal and a second frequency laser signal, or transmits a third frequency laser signal and a fourth frequency laser signal, or transmits a fifth frequency laser signal and a sixth frequency laser signal, etc., based on the laser frequency control signal.

[0047] The laser receiving unit includes a first sub-receiving unit and a second sub-receiving unit. The first sub-receiving unit is used to receive a first frequency laser signal, and the second sub-receiving unit is used to receive a second frequency laser signal. That is, the laser receiving unit transmits the first frequency laser signal and the second frequency laser signal to the preprocessing unit.

[0048] The preprocessing unit includes a photoelectric conversion module, a differential amplification module, and an AD conversion module. The differential amplification module is connected to both the photoelectric conversion module and the AD conversion module. The photoelectric conversion module performs voltage signal conversion processing on the first frequency laser signal and the second frequency laser signal, and transmits the signal to the differential amplification module. The differential amplification module receives the voltage signal transmitted from the photoelectric conversion module, performs signal gain adjustment processing, and transmits the signal to the AD conversion module. The AD conversion module receives the signal gain adjustment processing result from the differential amplification module, converts the signal gain adjustment processing result into a laser digital signal, and transmits it to the processor unit. The signal gain adjustment processing performed by the differential amplification module on the voltage signal transmitted from the photoelectric conversion module includes the following steps:

[0049] The differential amplifier module performs noise filtering on the voltage signal transmitted by the photoelectric conversion module.

[0050] The differential amplifier module adjusts the signal gain based on adjustable resistors 19 and 20 to obtain a gain adjustment signal with equal amplitude.

[0051] The differential amplifier module includes: resistors R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, adjustable resistors R19 and R20, capacitors C1, C2, C3, C4, C5, and C6, and operational amplifiers U1, U2, U3, U4, U5, U6, U7, and U8. The photoelectric conversion module is connected to the non-inverting input of operational amplifier U1. The non-inverting input terminals of operational amplifiers U1, U2, U3, and U4 are connected to each other. The negative-inverting input terminal of operational amplifier U1 is connected to one end of resistor R1, one end of resistor R5, and one end of capacitor C1. The negative-inverting input terminal of operational amplifier U2 is connected to one end of resistor R2, one end of resistor R6, and one end of capacitor C2. The negative-inverting input terminal of operational amplifier U3 is connected to one end of resistor R3, one end of resistor R7, and one end of capacitor C3. The negative-inverting input terminal of operational amplifier U4 is connected to one end of resistor R4, one end of resistor R8, and one end of capacitor C4. The other ends of resistors R1, R2, and R3 are connected to each other. The other ends of resistors R4 are grounded. The output of operational amplifier U1 is connected to one end of resistor R9, the other end of resistor R5, and the other end of capacitor C1. The output of operational amplifier U2 is connected to one end of resistor R11, the other end of resistor R6, and the other end of capacitor C2. The output of operational amplifier U3 is connected to one end of resistor R13, the other end of resistor R7, and the other end of capacitor C3. The output of operational amplifier U4 is connected to one end of resistor R15, the other end of resistor R8, and the other end of capacitor C4. The non-inverting input of operational amplifier U5 is connected to the other end of resistor R9 and one end of resistor R10. The non-inverting input of operational amplifier U5 is connected to resistor R1... The other end of resistor R12 is connected to the other end of the operational amplifier U6. The non-inverting input of operational amplifier U6 is connected to the other end of resistor R13 and one end of resistor R14. The non-inverting input of operational amplifier U6 is connected to the other end of resistor R15 and one end of resistor R16. The other ends of resistors R12 and R16 are both grounded. The output of operational amplifier U5 is connected to the other end of resistor R10 and the non-inverting input of operational amplifier U7. The output of operational amplifier U6 is connected to the other end of resistor R14 and the non-inverting input of operational amplifier U8. The non-inverting input of operational amplifier U7 is connected to one end of resistor R17, one end of adjustable resistor R19, and one end of capacitor C5.The negative input terminal of operational amplifier U8 is connected to one end of resistor R18, one end of adjustable resistor R20, and one end of capacitor C6. The output terminal of operational amplifier U7 is connected to the other end of adjustable resistor R19, the other end of capacitor C5, and the AD conversion module. The output terminal of operational amplifier U8 is connected to the other end of adjustable resistor R20, the other end of capacitor C6, and the AD conversion module. The other ends of resistors R17 and R18 are both grounded.

[0052] It should be noted that the differential amplifier module performs noise filtering on the voltage signal transmitted by the photoelectric conversion module, thereby improving the signal-to-noise ratio. The differential amplifier module receives the voltage signal transmitted by the photoelectric conversion module and performs signal gain adjustment processing. Specifically, the differential amplifier module adjusts the signal gain based on adjustable resistors 19 and 20 to obtain a gain adjustment signal with equal amplitude. This signal is then further processed by resistors R17 and R18, and capacitors C5 and C6 to filter out noise, thus improving the signal-to-noise ratio.

[0053] The tower bolt reflectivity unit comprises a reflectivity layer unit formed on the surface of the tower bolt. This reflectivity layer unit includes two or more reflectivity regions with different reflectivity. The reflectivity regions can be made of metallic materials. While the specific material of the reflectivity layer is not specified in this invention, it should be understood that simply increasing or decreasing the number or combination of material types in the reflectivity regions to create two or more reflectivity regions with different reflectivity falls within the scope of this invention. Optionally, the lengths of the two or more reflectivity regions with different reflectivity can be the same or different. For example, the reflectivity regions include a first reflectivity region, a second reflectivity region, a third reflectivity region, etc. The material of the first reflectivity region can be aluminum, the material of the second reflectivity region can be iron, the material of the third reflectivity region can be copper or other metallic materials, etc. The lengths of the first, second, and third reflectivity regions, etc., can be the same or different. Therefore, the number, length, and material of the reflectivity regions can be set according to actual usage.

[0054] It should be noted that by setting the number of reflectivity regions in the reflectivity layer unit on the surface of the tower bolts, when the tower bolts become loose, a laser signal is shone onto the reflectivity layer unit on the surface of the tower bolts. The laser signal exhibits different reflectivities in different reflectivity regions of the reflectivity layer unit. In other words, the looseness of the bolts is determined by the change in reflectivity when the laser signal shines on the reflectivity layer unit. Therefore, by setting the number of reflectivity regions in the reflectivity layer unit on the surface of the tower bolts, the accuracy of laser measurement of tower bolt loosening can be improved.

[0055] By setting the length of the reflectivity region of the reflectivity layer unit on the surface of the tower bolt, when the tower bolt becomes loose, the laser signal is transferred from the first reflectivity region of the reflectivity layer unit to the second, third, or other reflectivity regions, and so on. Based on the set length of each reflectivity region, the degree of looseness of the tower bolt can be determined. Therefore, by setting the length of the reflectivity region of the reflectivity layer on the surface of the tower bolt, the accuracy of laser measurement of the severity of tower bolt loosening can be improved.

[0056] The processor unit is used to determine the degree of looseness of tower bolts in the laser digital signal. The preprocessing unit transmits the laser digital signal to the processor unit, which receives the signal and performs the bolt looseness determination. The processor unit also transmits a laser frequency control signal to the laser emitting unit. The laser emitting unit receives the signal and emits laser signals of different frequencies based on the control signal; for example, it emits a first frequency laser signal and a second frequency laser signal.

[0057] The processor unit performs the following steps to determine the degree of looseness of tower bolts in the laser digital signal:

[0058] The processor unit performs laser feature extraction processing on the laser digital signal to obtain the reflectivity region characteristics of the laser-irradiated area and the reflectivity characteristics of the laser in the reflectivity layer unit of the tower bolt.

[0059] Based on the reflectivity characteristics of laser light in the reflectivity layer unit of tower bolts, it is determined whether the tower bolts are loose;

[0060] The degree of loosening of tower bolts is determined based on the reflectivity characteristics of the region illuminated by the laser and the reflectivity characteristics of the laser in the reflectivity layer unit of the tower bolts.

[0061] It should be noted that the processor unit performs laser feature extraction processing on the laser digital signal to obtain the reflectivity features of the region illuminated by the laser and the reflectivity features of the laser in the reflective layer. By analyzing these features, it is possible to determine whether the tower bolts are loose and the degree of looseness. For example, when the laser signal shifts from illuminating the first reflectivity region of the tower bolt reflectivity layer unit to illuminating the third reflectivity region, the laser feature extraction processing on the tower bolt laser signal yields the changes in reflectivity region and reflectivity of the tower bolt reflectivity layer unit illuminated by the laser signal. In other words, by observing the changes in reflectivity region and reflectivity, the accuracy of laser measurement of the looseness and degree of tower bolts can be achieved.

[0062] Based on the reflectivity characteristics of the laser on the reflectivity layer unit of the tower bolt, it is possible to determine whether the tower bolt is loose. For example, when the laser signal is transferred from the first reflectivity region of the tower bolt reflectivity layer unit to the second reflectivity region of the tower bolt reflectivity layer unit, since the reflectivity of the first reflectivity region is different from that of the second reflectivity region, the change in reflectivity when the laser signal is irradiated on the tower bolt reflectivity layer unit can be used to determine whether the bolt is loose. In other words, the change in the reflectivity characteristics of the laser on the tower bolt reflectivity layer unit can be used to quickly determine whether the tower bolt is loose.

[0063] Based on the characteristics of the reflectivity region illuminated by the laser and the reflectivity characteristics of the laser in the reflectivity layer unit of the tower bolt, the degree of looseness of the tower bolt can be determined. For example, when the laser signal moves from illuminating the first reflectivity region of the tower bolt reflectivity layer unit to illuminating the second, third, or other reflectivity regions of the tower bolt reflectivity layer unit, the characteristics of the reflectivity region illuminated by the laser and the reflectivity characteristics of the laser in the tower bolt reflectivity layer unit can be used to determine which reflectivity region of the tower bolt reflectivity layer unit the laser signal is illuminating. In other words, by using the characteristics of the reflectivity region illuminated by the laser and the reflectivity characteristics of the laser in the tower bolt reflectivity layer unit, the degree of looseness of the tower bolt can be accurately determined.

[0064] Optionally, to further improve the accuracy of measuring the looseness of tower bolts, the processor unit performs tower bolt loosening displacement compensation based on environmental factor signals around the tower and the expansion coefficient of the tower bolt reflectivity layer unit. The environmental factor signals around the tower include the temperature signal of the tower bolt reflectivity layer unit, air temperature and humidity signals, and ambient atmospheric pressure signals. The tower bolt loosening displacement compensation performed by the processor unit based on the environmental factor signals around the tower and the expansion coefficient of the tower bolt reflectivity layer unit includes the following steps:

[0065] Based on the expansion coefficient and temperature signal of the tower bolt reflectivity layer unit, the degree of expansion of the reflectivity region in the tower bolt reflectivity layer unit is determined.

[0066] The refractive index of ambient air is determined based on air temperature and humidity signals and ambient atmospheric pressure signals.

[0067] Based on the expansion degree of the reflectivity region in the reflectivity layer unit of the tower bolt and the refractive index of the ambient air, displacement compensation is performed on the loosening displacement of the tower bolt.

[0068] It should be noted that the reflectivity layer unit of the tower bolt includes two or more reflectivity regions with different reflectivity. The material of the reflectivity region can be iron, aluminum, copper, etc. Since different metals have different coefficients of expansion, the reflectivity regions of different metal materials have different degrees of expansion. By determining the degree of expansion of the reflectivity regions in the tower bolt reflectivity layer unit, the accuracy of tower bolt loosening displacement compensation can be improved.

Claims

1. A system for measuring the looseness of tower bolts based on laser signal gain adjustment, characterized in that, include: A laser emitting unit is used to emit a first frequency laser signal and a second frequency laser signal; A laser receiving unit, comprising a first sub-receiving unit and a second sub-receiving unit, wherein the first sub-receiving unit is used to receive a first frequency laser signal and the second sub-receiving unit is used to receive a second frequency laser signal; The preprocessing unit includes a photoelectric conversion module, a differential amplification module, and an AD conversion module. The differential amplification module is connected to both the photoelectric conversion module and the AD conversion module. The photoelectric conversion module performs voltage signal conversion processing on the first frequency laser signal and the second frequency laser signal, and transmits the signal to the differential amplification module. The differential amplification module receives the voltage signal transmitted from the photoelectric conversion module, performs signal gain adjustment processing, and transmits the signal to the AD conversion module. The AD conversion module receives the signal gain adjustment processing result transmitted from the differential amplification module, converts the signal gain adjustment processing result into a laser digital signal, and transmits it to the processor unit. A tower bolt reflectivity unit is formed by setting a tower bolt reflectivity layer unit on the surface of the tower bolt. The tower bolt reflectivity layer unit includes two or more reflectivity regions with different reflectivity. The processor unit is used to determine the degree of looseness of tower bolts from the laser digital signal, including the following steps: The processor unit performs laser feature extraction processing on the laser digital signal to obtain the reflectivity region characteristics of the laser-irradiated area and the reflectivity characteristics of the laser in the reflectivity layer unit of the tower bolt. Based on the reflectivity characteristics of laser light in the reflectivity layer unit of tower bolts, it is determined whether the tower bolts are loose; The degree of loosening of tower bolts is determined based on the reflectivity characteristics of the region illuminated by the laser and the reflectivity characteristics of the laser in the reflectivity layer unit of the tower bolts.

2. The system for measuring the looseness of tower bolts based on laser signal gain adjustment according to claim 1, characterized in that, The laser emitting unit includes a laser frequency emitting subunit, which emits laser signals of different frequencies based on a laser frequency control signal.

3. The system for measuring the looseness of tower bolts based on laser signal gain adjustment according to claim 2, characterized in that, The laser frequency emitting subunit emits laser signals of different frequencies based on a laser frequency control signal, including the following steps: The processor unit transmits the laser frequency control signal to the laser emitting unit; The laser emitting unit generates a laser frequency control signal based on the transmitted laser emitting control signal and transmits it to the laser frequency emitting subunit; The laser frequency emission subunit emits laser signals of different frequencies based on the laser frequency control signal.

4. The system for measuring the looseness of tower bolts based on laser signal gain adjustment according to claim 1, characterized in that, The differential amplifier module includes: resistors R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, and R18; adjustable resistors R19 and R20; capacitors C1, C2, C3, C4, C5, and C6; and operational amplifiers U1, U2, U3, U4, U5, U6, U7, and U8. The photoelectric conversion module is connected to the non-inverting input terminal of operational amplifier U1 and the operational amplifier... The non-inverting input terminals of operational amplifiers U2, U3, and U4 are connected. The negative-inverting input terminal of operational amplifier U1 is connected to one end of resistor R1, one end of resistor R6, and one end of capacitor C1. The negative-inverting input terminal of operational amplifier U2 is connected to one end of resistor R2, one end of resistor R6, and one end of capacitor C2. The negative-inverting input terminal of operational amplifier U3 is connected to one end of resistor R3, one end of resistor R7, and one end of capacitor C3. The negative-inverting input terminal of operational amplifier U4 is connected to one end of resistor R4, one end of resistor R8, and one end of capacitor C4. The other ends of resistors R1, R2, R3, and R4 are connected. The other ends of all are grounded. The output terminals of operational amplifier U1 are connected to one end of resistor R9, the other end of resistor R5, and the other end of capacitor C1, respectively. The output terminals of operational amplifier U2 are connected to one end of resistor R11, the other end of resistor R6, and the other end of capacitor C2, respectively. The output terminals of operational amplifier U3 are connected to one end of resistor R13, the other end of resistor R7, and the other end of capacitor C3, respectively. The output terminals of operational amplifier U4 are connected to one end of resistor R15, the other end of resistor R8, and the other end of capacitor C4, respectively. The non-inverting input terminal of operational amplifier U5 is connected to the other end of resistor R9 and one end of resistor R10, respectively. The non-inverting input terminal of operational amplifier U5 is connected to the other end of resistor R11, the other end of resistor R6, and the other end of capacitor C2, respectively. The other end of the resistor is connected to one end of resistor R12. The non-inverting input of operational amplifier U6 is connected to the other end of resistor R13 and one end of resistor R14. The negative-inverting input of operational amplifier U6 is connected to the other end of resistor R15 and one end of resistor R16. The other ends of resistors R12 and R16 are both grounded. The output of operational amplifier U5 is connected to the other end of resistor R10 and the non-inverting input of operational amplifier U7. The output of operational amplifier U6 is connected to the other end of resistor R14 and the non-inverting input of operational amplifier U8. The negative-inverting input of operational amplifier U7 is connected to one end of resistor R17, one end of adjustable resistor R19, and one end of capacitor C5.The negative input terminal of operational amplifier U8 is connected to one end of resistor R18, one end of adjustable resistor R20, and one end of capacitor C6. The output terminal of operational amplifier U7 is connected to the other end of adjustable resistor R19, the other end of capacitor C5, and the AD conversion module. The output terminal of operational amplifier U8 is connected to the other end of adjustable resistor R20, the other end of capacitor C6, and the AD conversion module. The other ends of resistors R17 and R18 are both grounded.

5. The system for measuring the looseness of tower bolts based on laser signal gain adjustment according to claim 4, characterized in that, The differential amplifier module receives the voltage signal transmitted by the photoelectric conversion module and performs signal gain adjustment processing, including the following steps: The differential amplifier module performs noise filtering on the voltage signal transmitted by the photoelectric conversion module. The differential amplifier module adjusts the signal gain based on adjustable resistors R19 and R20 to obtain a gain adjustment signal with equal amplitude.

6. The system for measuring the looseness of tower bolts based on laser signal gain adjustment according to claim 1, characterized in that, The reflectivity region of the tower bolt reflectivity layer unit is made of metallic material.

7. The system for measuring the looseness of tower bolts based on laser signal gain adjustment according to claim 1, characterized in that, The processor unit performs tower bolt loosening displacement compensation based on environmental factor signals around the tower and the expansion coefficient of the tower bolt reflectivity layer unit.

8. The system for measuring the looseness of tower bolts based on laser signal gain adjustment according to claim 7, characterized in that, The environmental factor signals around the tower include the temperature signal of the tower bolt reflectivity layer unit, the air temperature and humidity signal, and the ambient atmospheric pressure signal.

9. The system for measuring the looseness of tower bolts based on laser signal gain adjustment according to claim 7, characterized in that, The processor unit performs tower bolt loosening displacement compensation based on environmental factor signals around the tower and the expansion coefficient of the tower bolt reflectivity layer unit, including the following steps: Based on the expansion coefficient and temperature signal of the tower bolt reflectivity layer unit, the degree of expansion of the reflectivity region in the tower bolt reflectivity layer unit is determined. The refractive index of ambient air is determined based on air temperature and humidity signals and ambient atmospheric pressure signals. Based on the expansion degree of the reflectivity region in the reflectivity layer unit of the tower bolt and the refractive index of the ambient air, displacement compensation is performed on the loosening displacement of the tower bolt.